Style fixes (#396)

* Fix p2p * Cosmetic stuff * More cosmetics * Whitespace * Whitespace * Whitespace * Renames * Most cosmetics * typo * minor rename * Remote-end disconnect message should be info! * invalid tab * Avoid ignoring sustained bad pings * Remove workarounds.
2026-05-01 05:27:56 +00:00 · 2018-07-23 16:46:13 +02:00
parent fcb30f4009
commit 077c3d3cb7
17 changed files with 628 additions and 612 deletions
@@ -49,7 +49,7 @@ use parking_lot::Mutex;
 use polkadot_consensus::{Statement, SignedStatement, GenericStatement};
 use polkadot_primitives::{AccountId, Block, SessionKey, Hash, Header};
 use polkadot_primitives::parachain::{Id as ParaId, BlockData, Extrinsic, CandidateReceipt, Collation};
-use substrate_network::{PeerId, RequestId, Context, Severity};
+use substrate_network::{NodeIndex, RequestId, Context, Severity};
 use substrate_network::consensus_gossip::ConsensusGossip;
 use substrate_network::{message, generic_message};
 use substrate_network::specialization::Specialization;
@@ -244,7 +244,7 @@ impl Decode for Message {
 	}
 }

-fn send_polkadot_message(ctx: &mut Context<Block>, to: PeerId, message: Message) {
+fn send_polkadot_message(ctx: &mut Context<Block>, to: NodeIndex, message: Message) {
 	trace!(target: "p_net", "Sending polkadot message to {}: {:?}", to, message);
 	let encoded = message.encode();
 	ctx.send_message(to, generic_message::Message::ChainSpecific(encoded))
@@ -252,14 +252,14 @@ fn send_polkadot_message(ctx: &mut Context<Block>, to: PeerId, message: Message)

 /// Polkadot protocol attachment for substrate.
 pub struct PolkadotProtocol {
-	peers: HashMap<PeerId, PeerInfo>,
+	peers: HashMap<NodeIndex, PeerInfo>,
 	collating_for: Option<(AccountId, ParaId)>,
 	consensus_gossip: ConsensusGossip<Block>,
 	collators: CollatorPool,
-	validators: HashMap<SessionKey, PeerId>,
+	validators: HashMap<SessionKey, NodeIndex>,
 	local_collations: LocalCollations<Collation>,
 	live_consensus: Option<CurrentConsensus>,
-	in_flight: HashMap<(RequestId, PeerId), BlockDataRequest>,
+	in_flight: HashMap<(RequestId, NodeIndex), BlockDataRequest>,
 	pending: Vec<BlockDataRequest>,
 	next_req_id: u64,
 }
@@ -352,17 +352,17 @@ impl PolkadotProtocol {
 					.map(|(_, id)| id);

 				// dispatch to peer
-				if let Some(peer_id) = next_peer {
+				if let Some(who) = next_peer {
 					let req_id = self.next_req_id;
 					self.next_req_id += 1;

 					send_polkadot_message(
 						ctx,
-						peer_id,
+						who,
 						Message::RequestBlockData(req_id, pending.candidate_hash)
 					);

-					self.in_flight.insert((req_id, peer_id), pending);
+					self.in_flight.insert((req_id, who), pending);

 					continue;
 				}
@@ -374,36 +374,36 @@ impl PolkadotProtocol {
 		self.pending = new_pending;
 	}

-	fn on_polkadot_message(&mut self, ctx: &mut Context<Block>, peer_id: PeerId, raw: Vec<u8>, msg: Message) {
-		trace!(target: "p_net", "Polkadot message from {}: {:?}", peer_id, msg);
+	fn on_polkadot_message(&mut self, ctx: &mut Context<Block>, who: NodeIndex, raw: Vec<u8>, msg: Message) {
+		trace!(target: "p_net", "Polkadot message from {}: {:?}", who, msg);
 		match msg {
 			Message::Statement(parent_hash, _statement) =>
-				self.consensus_gossip.on_chain_specific(ctx, peer_id, raw, parent_hash),
-			Message::SessionKey(key) => self.on_session_key(ctx, peer_id, key),
+				self.consensus_gossip.on_chain_specific(ctx, who, raw, parent_hash),
+			Message::SessionKey(key) => self.on_session_key(ctx, who, key),
 			Message::RequestBlockData(req_id, hash) => {
 				let block_data = self.live_consensus.as_ref()
 					.and_then(|c| c.block_data(&hash));

-				send_polkadot_message(ctx, peer_id, Message::BlockData(req_id, block_data));
+				send_polkadot_message(ctx, who, Message::BlockData(req_id, block_data));
 			}
-			Message::BlockData(req_id, data) => self.on_block_data(ctx, peer_id, req_id, data),
-			Message::Collation(relay_parent, collation) => self.on_collation(ctx, peer_id, relay_parent, collation),
-			Message::CollatorRole(role) => self.on_new_role(ctx, peer_id, role),
+			Message::BlockData(req_id, data) => self.on_block_data(ctx, who, req_id, data),
+			Message::Collation(relay_parent, collation) => self.on_collation(ctx, who, relay_parent, collation),
+			Message::CollatorRole(role) => self.on_new_role(ctx, who, role),
 		}
 	}

-	fn on_session_key(&mut self, ctx: &mut Context<Block>, peer_id: PeerId, key: SessionKey) {
+	fn on_session_key(&mut self, ctx: &mut Context<Block>, who: NodeIndex, key: SessionKey) {
 		{
-			let info = match self.peers.get_mut(&peer_id) {
+			let info = match self.peers.get_mut(&who) {
 				Some(peer) => peer,
 				None => {
-					trace!(target: "p_net", "Network inconsistency: message received from unconnected peer {}", peer_id);
+					trace!(target: "p_net", "Network inconsistency: message received from unconnected peer {}", who);
 					return
 				}
 			};

 			if !info.claimed_validator {
-				ctx.report_peer(peer_id, Severity::Bad("Session key broadcasted without setting authority role"));
+				ctx.report_peer(who, Severity::Bad("Session key broadcasted without setting authority role"));
 				return;
 			}

@@ -413,20 +413,20 @@ impl PolkadotProtocol {
 				for (relay_parent, collation) in self.local_collations.fresh_key(&old_key, &key) {
 					send_polkadot_message(
 						ctx,
-						peer_id,
+						who,
 						Message::Collation(relay_parent, collation),
 					)
 				}

 			}
-			self.validators.insert(key, peer_id);
+			self.validators.insert(key, who);
 		}

 		self.dispatch_pending_requests(ctx);
 	}

-	fn on_block_data(&mut self, ctx: &mut Context<Block>, peer_id: PeerId, req_id: RequestId, data: Option<BlockData>) {
-		match self.in_flight.remove(&(req_id, peer_id)) {
+	fn on_block_data(&mut self, ctx: &mut Context<Block>, who: NodeIndex, req_id: RequestId, data: Option<BlockData>) {
+		match self.in_flight.remove(&(req_id, who)) {
 			Some(req) => {
 				if let Some(data) = data {
 					if data.hash() == req.block_data_hash {
@@ -438,29 +438,29 @@ impl PolkadotProtocol {
 				self.pending.push(req);
 				self.dispatch_pending_requests(ctx);
 			}
-			None => ctx.report_peer(peer_id, Severity::Bad("Unexpected block data response")),
+			None => ctx.report_peer(who, Severity::Bad("Unexpected block data response")),
 		}
 	}

 	// when a validator sends us (a collator) a new role.
-	fn on_new_role(&mut self, ctx: &mut Context<Block>, peer_id: PeerId, role: Role) {
-		let info = match self.peers.get(&peer_id) {
+	fn on_new_role(&mut self, ctx: &mut Context<Block>, who: NodeIndex, role: Role) {
+		let info = match self.peers.get(&who) {
 			Some(peer) => peer,
 			None => {
-				trace!(target: "p_net", "Network inconsistency: message received from unconnected peer {}", peer_id);
+				trace!(target: "p_net", "Network inconsistency: message received from unconnected peer {}", who);
 				return
 			}
 		};

 		match info.validator_key {
 			None => ctx.report_peer(
-				peer_id,
+				who,
 				Severity::Bad("Sent collator role without registering first as validator"),
 			),
 			Some(key) => for (relay_parent, collation) in self.local_collations.note_validator_role(key, role) {
 				send_polkadot_message(
 					ctx,
-					peer_id,
+					who,
 					Message::Collation(relay_parent, collation),
 				)
 			},
@@ -473,7 +473,7 @@ impl Specialization<Block> for PolkadotProtocol {
 		Status { collating_for: self.collating_for.clone() }.encode()
 	}

-	fn on_connect(&mut self, ctx: &mut Context<Block>, peer_id: PeerId, status: FullStatus) {
+	fn on_connect(&mut self, ctx: &mut Context<Block>, who: NodeIndex, status: FullStatus) {
 		let local_status = match Status::decode(&mut &status.chain_status[..]) {
 			Some(status) => status,
 			None => {
@@ -483,14 +483,14 @@ impl Specialization<Block> for PolkadotProtocol {

 		if let Some((ref acc_id, ref para_id)) = local_status.collating_for {
 			if self.collator_peer_id(acc_id.clone()).is_some() {
-				ctx.report_peer(peer_id, Severity::Useless("Unknown Polkadot-specific reason"));
+				ctx.report_peer(who, Severity::Useless("Unknown Polkadot-specific reason"));
 				return
 			}

 			let collator_role = self.collators.on_new_collator(acc_id.clone(), para_id.clone());
 			send_polkadot_message(
 				ctx,
-				peer_id,
+				who,
 				Message::CollatorRole(collator_role),
 			);
 		}
@@ -498,17 +498,17 @@ impl Specialization<Block> for PolkadotProtocol {
 		let validator = status.roles.contains(substrate_network::Roles::AUTHORITY);
 		let send_key = validator || local_status.collating_for.is_some();

-		self.peers.insert(peer_id, PeerInfo {
+		self.peers.insert(who, PeerInfo {
 			collating_for: local_status.collating_for,
 			validator_key: None,
 			claimed_validator: validator,
 		});

-		self.consensus_gossip.new_peer(ctx, peer_id, status.roles);
+		self.consensus_gossip.new_peer(ctx, who, status.roles);
 		if let (true, &Some(ref consensus)) = (send_key, &self.live_consensus) {
 			send_polkadot_message(
 				ctx,
-				peer_id,
+				who,
 				Message::SessionKey(consensus.local_session_key)
 			);
 		}
@@ -516,8 +516,8 @@ impl Specialization<Block> for PolkadotProtocol {
 		self.dispatch_pending_requests(ctx);
 	}

-	fn on_disconnect(&mut self, ctx: &mut Context<Block>, peer_id: PeerId) {
-		if let Some(info) = self.peers.remove(&peer_id) {
+	fn on_disconnect(&mut self, ctx: &mut Context<Block>, who: NodeIndex) {
+		if let Some(info) = self.peers.remove(&who) {
 			if let Some((acc_id, _)) = info.collating_for {
 				let new_primary = self.collators.on_disconnect(acc_id)
 					.and_then(|new_primary| self.collator_peer_id(new_primary));
@@ -539,7 +539,7 @@ impl Specialization<Block> for PolkadotProtocol {
 			{
 				let pending = &mut self.pending;
 				self.in_flight.retain(|&(_, ref peer), val| {
-					let retain = peer != &peer_id;
+					let retain = peer != &who;
 					if !retain {
 						let (sender, _) = oneshot::channel();
 						pending.push(::std::mem::replace(val, BlockDataRequest {
@@ -554,24 +554,24 @@ impl Specialization<Block> for PolkadotProtocol {
 					retain
 				});
 			}
-			self.consensus_gossip.peer_disconnected(ctx, peer_id);
+			self.consensus_gossip.peer_disconnected(ctx, who);
 			self.dispatch_pending_requests(ctx);
 		}
 	}

-	fn on_message(&mut self, ctx: &mut Context<Block>, peer_id: PeerId, message: message::Message<Block>) {
+	fn on_message(&mut self, ctx: &mut Context<Block>, who: NodeIndex, message: message::Message<Block>) {
 		match message {
 			generic_message::Message::BftMessage(msg) => {
-				trace!(target: "p_net", "Polkadot BFT message from {}: {:?}", peer_id, msg);
+				trace!(target: "p_net", "Polkadot BFT message from {}: {:?}", who, msg);
 				// TODO: check signature here? what if relevant block is unknown?
-				self.consensus_gossip.on_bft_message(ctx, peer_id, msg)
+				self.consensus_gossip.on_bft_message(ctx, who, msg)
 			}
 			generic_message::Message::ChainSpecific(raw) => {
 				match Message::decode(&mut raw.as_slice()) {
-					Some(msg) => self.on_polkadot_message(ctx, peer_id, raw, msg),
+					Some(msg) => self.on_polkadot_message(ctx, who, raw, msg),
 					None => {
-						trace!(target: "p_net", "Bad message from {}", peer_id);
-						ctx.report_peer(peer_id, Severity::Bad("Invalid polkadot protocol message format"));
+						trace!(target: "p_net", "Bad message from {}", who);
+						ctx.report_peer(who, Severity::Bad("Invalid polkadot protocol message format"));
 					}
 				}
 			}
@@ -611,7 +611,7 @@ impl Specialization<Block> for PolkadotProtocol {

 impl PolkadotProtocol {
 	// we received a collation from a peer
-	fn on_collation(&mut self, ctx: &mut Context<Block>, from: PeerId, relay_parent: Hash, collation: Collation) {
+	fn on_collation(&mut self, ctx: &mut Context<Block>, from: NodeIndex, relay_parent: Hash, collation: Collation) {
 		let collation_para = collation.receipt.parachain_index;
 		let collated_acc = collation.receipt.collator;

@@ -638,7 +638,7 @@ impl PolkadotProtocol {
 	}

 	// get connected peer with given account ID for collation.
-	fn collator_peer_id(&self, account_id: AccountId) -> Option<PeerId> {
+	fn collator_peer_id(&self, account_id: AccountId) -> Option<NodeIndex> {
 		let check_info = |info: &PeerInfo| info
 			.collating_for
 			.as_ref()
@@ -647,14 +647,14 @@ impl PolkadotProtocol {
 		self.peers
 			.iter()
 			.filter(|&(_, info)| check_info(info))
-			.map(|(peer_id, _)| *peer_id)
+			.map(|(who, _)| *who)
 			.next()
 	}

 	// disconnect a collator by account-id.
 	fn disconnect_bad_collator(&self, ctx: &mut Context<Block>, account_id: AccountId) {
-		if let Some(peer_id) = self.collator_peer_id(account_id) {
-			ctx.report_peer(peer_id, Severity::Bad("Consensus layer determined the given collator misbehaved"))
+		if let Some(who) = self.collator_peer_id(account_id) {
+			ctx.report_peer(who, Severity::Bad("Consensus layer determined the given collator misbehaved"))
 		}
 	}
 }
@@ -670,9 +670,9 @@ impl PolkadotProtocol {
 	) {
 		for (primary, cloned_collation) in self.local_collations.add_collation(relay_parent, targets, collation.clone()) {
 			match self.validators.get(&primary) {
-				Some(peer_id) => send_polkadot_message(
+				Some(who) => send_polkadot_message(
 					ctx,
-					*peer_id,
+					*who,
 					Message::Collation(relay_parent, cloned_collation),
 				),
 				None =>
@@ -24,16 +24,16 @@ use polkadot_primitives::{Block, Hash, SessionKey};
 use polkadot_primitives::parachain::{CandidateReceipt, HeadData, BlockData};
 use substrate_primitives::H512;
 use codec::Encode;
-use substrate_network::{Severity, PeerId, PeerInfo, ClientHandle, Context, Roles, message::Message as SubstrateMessage, specialization::Specialization, generic_message::Message as GenericMessage};
+use substrate_network::{Severity, NodeIndex, PeerInfo, ClientHandle, Context, Roles, message::Message as SubstrateMessage, specialization::Specialization, generic_message::Message as GenericMessage};

 use std::sync::Arc;
 use futures::Future;

 #[derive(Default)]
 struct TestContext {
-	disabled: Vec<PeerId>,
-	disconnected: Vec<PeerId>,
-	messages: Vec<(PeerId, SubstrateMessage<Block>)>,
+	disabled: Vec<NodeIndex>,
+	disconnected: Vec<NodeIndex>,
+	messages: Vec<(NodeIndex, SubstrateMessage<Block>)>,
 }

 impl Context<Block> for TestContext {
@@ -41,24 +41,24 @@ impl Context<Block> for TestContext {
 		unimplemented!()
 	}

-	fn report_peer(&mut self, peer: PeerId, reason: Severity) {
+	fn report_peer(&mut self, peer: NodeIndex, reason: Severity) {
 		match reason {
 			Severity::Bad(_) => self.disabled.push(peer),
 			_ => self.disconnected.push(peer),
 		}
 	}

-	fn peer_info(&self, _peer: PeerId) -> Option<PeerInfo<Block>> {
+	fn peer_info(&self, _peer: NodeIndex) -> Option<PeerInfo<Block>> {
 		unimplemented!()
 	}

-	fn send_message(&mut self, peer_id: PeerId, data: SubstrateMessage<Block>) {
-		self.messages.push((peer_id, data))
+	fn send_message(&mut self, who: NodeIndex, data: SubstrateMessage<Block>) {
+		self.messages.push((who, data))
 	}
 }

 impl TestContext {
-	fn has_message(&self, to: PeerId, message: Message) -> bool {
+	fn has_message(&self, to: NodeIndex, message: Message) -> bool {
 		use substrate_network::generic_message::Message as GenericMessage;

 		let encoded = message.encode();
@@ -91,7 +91,7 @@ fn make_consensus(parent_hash: Hash, local_key: SessionKey) -> (CurrentConsensus
 	(c, knowledge)
 }

-fn on_message(protocol: &mut PolkadotProtocol, ctx: &mut TestContext, from: PeerId, message: Message) {
+fn on_message(protocol: &mut PolkadotProtocol, ctx: &mut TestContext, from: NodeIndex, message: Message) {
 	let encoded = message.encode();
 	protocol.on_message(ctx, from, GenericMessage::ChainSpecific(encoded));
 }
@@ -209,19 +209,19 @@ fn fetches_from_those_with_knowledge() {
 fn remove_bad_collator() {
 	let mut protocol = PolkadotProtocol::new(None);

-	let peer_id = 1;
+	let who = 1;
 	let account_id = [2; 32].into();

 	let status = Status { collating_for: Some((account_id, 5.into())) };

 	{
 		let mut ctx = TestContext::default();
-		protocol.on_connect(&mut ctx, peer_id, make_status(&status, Roles::NONE));
+		protocol.on_connect(&mut ctx, who, make_status(&status, Roles::NONE));
 	}

 	{
 		let mut ctx = TestContext::default();
 		protocol.disconnect_bad_collator(&mut ctx, account_id);
-		assert!(ctx.disabled.contains(&peer_id));
+		assert!(ctx.disabled.contains(&who));
 	}
 }
@@ -18,7 +18,7 @@ use bytes::Bytes;
 use fnv::{FnvHashMap, FnvHashSet};
 use futures::sync::mpsc;
 use libp2p::core::{multiaddr::ToMultiaddr, Multiaddr, AddrComponent, Endpoint, UniqueConnec};
-use libp2p::core::{UniqueConnecState, PeerId as PeerstorePeerId, PublicKey};
+use libp2p::core::{UniqueConnecState, PeerId, PublicKey};
 use libp2p::kad::KadConnecController;
 use libp2p::peerstore::{Peerstore, PeerAccess};
 use libp2p::peerstore::json_peerstore::JsonPeerstore;
@@ -26,7 +26,7 @@ use libp2p::peerstore::memory_peerstore::MemoryPeerstore;
 use libp2p::ping::Pinger;
 use libp2p::secio;
 use {Error, ErrorKind, NetworkConfiguration, NonReservedPeerMode};
-use {PeerId, ProtocolId, SessionInfo};
+use {NodeIndex, ProtocolId, SessionInfo};
 use parking_lot::{Mutex, RwLock};
 use rand::{self, Rng};
 use std::cmp;
@@ -46,7 +46,7 @@ const PEER_DISABLE_DURATION: Duration = Duration::from_secs(5 * 60);
 // Common struct shared throughout all the components of the service.
 pub struct NetworkState {
 	/// Contains the information about the network.
-	peerstore: PeersStorage,
+	node_store: NodeStore,

 	/// Active connections.
 	connections: RwLock<Connections>,
@@ -59,14 +59,14 @@ pub struct NetworkState {
 	/// If true, only reserved peers can connect.
 	reserved_only: atomic::AtomicBool,
 	/// List of the IDs of the reserved peers.
-	reserved_peers: RwLock<FnvHashSet<PeerstorePeerId>>,
+	reserved_peers: RwLock<FnvHashSet<PeerId>>,

-	/// Each peer gets assigned a new unique ID. This ID increases linearly.
-	next_peer_id: atomic::AtomicUsize,
+	/// Each node we discover gets assigned a new unique ID. This ID increases linearly.
+	next_node_index: atomic::AtomicUsize,

 	/// List of the IDs of the disabled peers. These peers will see their
 	/// connections refused. Includes the time when the disabling expires.
-	disabled_peers: Mutex<FnvHashMap<PeerstorePeerId, Instant>>,
+	disabled_nodes: Mutex<FnvHashMap<PeerId, Instant>>,

 	/// Local private key.
 	local_private_key: secio::SecioKeyPair,
@@ -74,7 +74,7 @@ pub struct NetworkState {
 	local_public_key: PublicKey,
 }

-enum PeersStorage {
+enum NodeStore {
 	/// Peers are stored in memory. Nothing is stored on disk.
 	Memory(MemoryPeerstore),
 	/// Peers are stored in a JSON file on the disk.
@@ -84,10 +84,10 @@ enum PeersStorage {
 struct Connections {
 	/// For each libp2p peer ID, the ID of the peer in the API we expose.
 	/// Also corresponds to the index in `info_by_peer`.
-	peer_by_nodeid: FnvHashMap<PeerstorePeerId, usize>,
+	peer_by_nodeid: FnvHashMap<PeerId, usize>,

 	/// For each peer ID, information about our connection to this peer.
-	info_by_peer: FnvHashMap<PeerId, PeerConnectionInfo>,
+	info_by_peer: FnvHashMap<NodeIndex, PeerConnectionInfo>,
 }

 struct PeerConnectionInfo {
@@ -104,7 +104,7 @@ struct PeerConnectionInfo {
 	ping_connec: UniqueConnec<Pinger>,

 	/// Id of the peer.
-	id: PeerstorePeerId,
+	id: PeerId,

 	/// True if this connection was initiated by us.
 	/// Note that it is theoretically possible that we dial the remote at the
@@ -130,7 +130,7 @@ struct PeerConnectionInfo {
 #[derive(Debug, Clone)]
 pub struct PeerInfo {
 	/// Id of the peer.
-	pub id: PeerstorePeerId,
+	pub id: PeerId,

 	/// True if this connection was initiated by us.
 	/// Note that it is theoretically possible that we dial the remote at the
@@ -172,21 +172,21 @@ impl NetworkState {
 		let local_public_key = local_private_key.to_public_key();

 		// Build the storage for peers, including the bootstrap nodes.
-		let peerstore = if let Some(ref path) = config.net_config_path {
+		let node_store = if let Some(ref path) = config.net_config_path {
 			let path = Path::new(path).join(NODES_FILE);
-			if let Ok(peerstore) = JsonPeerstore::new(path.clone()) {
+			if let Ok(node_store) = JsonPeerstore::new(path.clone()) {
 				debug!(target: "sub-libp2p", "Initialized peer store for JSON \
 					file {:?}", path);
-				PeersStorage::Json(peerstore)
+				NodeStore::Json(node_store)
 			} else {
 				warn!(target: "sub-libp2p", "Failed to open peer storage {:?} \
 					; peers won't be saved", path);
-				PeersStorage::Memory(MemoryPeerstore::empty())
+				NodeStore::Memory(MemoryPeerstore::empty())
 			}
 		} else {
 			debug!(target: "sub-libp2p", "No peers file configured ; peers \
 				won't be saved");
-			PeersStorage::Memory(MemoryPeerstore::empty())
+			NodeStore::Memory(MemoryPeerstore::empty())
 		};

 		let reserved_peers = {
@@ -195,7 +195,7 @@ impl NetworkState {
 				Default::default()
 			);
 			for peer in config.reserved_nodes.iter() {
-				let id = parse_and_add_to_peerstore(peer, &peerstore)?;
+				let id = parse_and_add_to_node_store(peer, &node_store)?;
 				reserved_peers.insert(id);
 			}
 			RwLock::new(reserved_peers)
@@ -205,7 +205,7 @@ impl NetworkState {
 			config.reserved_nodes.len());

 		Ok(NetworkState {
-			peerstore,
+			node_store,
 			min_peers: config.min_peers,
 			max_peers: config.max_peers,
 			connections: RwLock::new(Connections {
@@ -214,8 +214,8 @@ impl NetworkState {
 			}),
 			reserved_only: atomic::AtomicBool::new(false),
 			reserved_peers,
-			next_peer_id: atomic::AtomicUsize::new(0),
-			disabled_peers: Mutex::new(Default::default()),
+			next_node_index: atomic::AtomicUsize::new(0),
+			disabled_nodes: Mutex::new(Default::default()),
 			local_private_key,
 			local_public_key,
 		})
@@ -234,13 +234,13 @@ impl NetworkState {
 	/// Returns the ID of a random peer of the network.
 	///
 	/// Returns `None` if we don't know any peer.
-	pub fn random_peer(&self) -> Option<PeerstorePeerId> {
-		// TODO: optimize by putting the operation directly in the peerstore
+	pub fn random_peer(&self) -> Option<PeerId> {
+		// TODO: optimize by putting the operation directly in the node_store
 		// https://github.com/libp2p/rust-libp2p/issues/316
-		let peers = match self.peerstore {
-			PeersStorage::Memory(ref mem) =>
+		let peers = match self.node_store {
+			NodeStore::Memory(ref mem) =>
 				mem.peers().collect::<Vec<_>>(),
-			PeersStorage::Json(ref json) =>
+			NodeStore::Json(ref json) =>
 				json.peers().collect::<Vec<_>>(),
 		};

@@ -255,11 +255,11 @@ impl NetworkState {
 	/// Returns all the IDs of the peers on the network we have knowledge of.
 	///
 	/// This includes peers we are not connected to.
-	pub fn known_peers(&self) -> impl Iterator<Item = PeerstorePeerId> {
-		match self.peerstore {
-			PeersStorage::Memory(ref mem) =>
+	pub fn known_peers(&self) -> impl Iterator<Item = PeerId> {
+		match self.node_store {
+			NodeStore::Memory(ref mem) =>
 				mem.peers().collect::<Vec<_>>().into_iter(),
-			PeersStorage::Json(ref json) =>
+			NodeStore::Json(ref json) =>
 				json.peers().collect::<Vec<_>>().into_iter(),
 		}
 	}
@@ -270,34 +270,32 @@ impl NetworkState {
 	}

 	/// Get a list of all connected peers by id.
-	pub fn connected_peers(&self) -> Vec<PeerId> {
+	pub fn connected_peers(&self) -> Vec<NodeIndex> {
 		self.connections.read().peer_by_nodeid.values().cloned().collect()
 	}

-	/// Returns true if the given `PeerId` is valid.
+	/// Returns true if the given `NodeIndex` is valid.
 	///
-	/// `PeerId`s are never reused, so once this function returns `false` it
-	/// will never return `true` again for the same `PeerId`.
-	pub fn is_peer_connected(&self, peer: PeerId) -> bool {
+	/// `NodeIndex`s are never reused, so once this function returns `false` it
+	/// will never return `true` again for the same `NodeIndex`.
+	pub fn is_peer_connected(&self, peer: NodeIndex) -> bool {
 		self.connections.read().info_by_peer.contains_key(&peer)
 	}

 	/// Reports the ping of the peer. Returned later by `session_info()`.
-	/// No-op if the `peer_id` is not valid/expired.
-	pub fn report_ping_duration(&self, peer_id: PeerId, ping: Duration) {
-		let connections = self.connections.read();
-		let info = match connections.info_by_peer.get(&peer_id) {
+	/// No-op if the `who` is not valid/expired.
+	pub fn report_ping_duration(&self, who: NodeIndex, ping: Duration) {
+		let mut connections = self.connections.write();
+		let info = match connections.info_by_peer.get_mut(&who) {
 			Some(info) => info,
 			None => return,
 		};
-
 		*info.ping.lock() = Some(ping);
 	}

 	/// If we're connected to a peer with the given protocol, returns
 	/// information about the connection. Otherwise, returns `None`.
-	pub fn session_info(&self, peer: PeerId, protocol: ProtocolId)
-		-> Option<SessionInfo> {
+	pub fn session_info(&self, peer: NodeIndex, protocol: ProtocolId) -> Option<SessionInfo> {
 		let connections = self.connections.read();
 		let info = match connections.info_by_peer.get(&peer) {
 			Some(info) => info,
@@ -333,8 +331,7 @@ impl NetworkState {

 	/// If we're connected to a peer with the given protocol, returns the
 	/// protocol version. Otherwise, returns `None`.
-	pub fn protocol_version(&self, peer: PeerId, protocol: ProtocolId)
-		-> Option<u8> {
+	pub fn protocol_version(&self, peer: NodeIndex, protocol: ProtocolId) -> Option<u8> {
 		let connections = self.connections.read();
 		let peer = match connections.info_by_peer.get(&peer) {
 			Some(peer) => peer,
@@ -348,8 +345,7 @@ impl NetworkState {
 	}

 	/// Equivalent to `session_info(peer).map(|info| info.client_version)`.
-	pub fn peer_client_version(&self, peer: PeerId, protocol: ProtocolId)
-		-> Option<String> {
+	pub fn peer_client_version(&self, peer: NodeIndex, protocol: ProtocolId) -> Option<String> {
 		// TODO: implement more directly, without going through `session_info`
 		self.session_info(peer, protocol)
 			.map(|info| info.client_version)
@@ -357,14 +353,14 @@ impl NetworkState {

 	/// Adds an address discovered by Kademlia.
 	/// Note that we don't have to be connected to a peer to add an address.
-	pub fn add_kad_discovered_addr(&self, node_id: &PeerstorePeerId, addr: Multiaddr) {
+	pub fn add_kad_discovered_addr(&self, node_id: &PeerId, addr: Multiaddr) {
 		trace!(target: "sub-libp2p", "Peer store: adding address {} for {:?}",
 			addr, node_id);
-		match self.peerstore {
-			PeersStorage::Memory(ref mem) =>
+		match self.node_store {
+			NodeStore::Memory(ref mem) =>
 				mem.peer_or_create(node_id)
 					.add_addr(addr, Duration::from_secs(3600)),
-			PeersStorage::Json(ref json) =>
+			NodeStore::Json(ref json) =>
 				json.peer_or_create(node_id)
 					.add_addr(addr, Duration::from_secs(3600)),
 		}
@@ -373,15 +369,14 @@ impl NetworkState {
 	/// Signals that an address doesn't match the corresponding node ID.
 	/// This removes the address from the peer store, so that it is not
 	/// returned by `addrs_of_peer` again in the future.
-	pub fn set_invalid_kad_address(&self, node_id: &PeerstorePeerId,
-		addr: &Multiaddr) {
+	pub fn set_invalid_kad_address(&self, node_id: &PeerId, addr: &Multiaddr) {
 		// TODO: blacklist the address?
-		match self.peerstore {
-			PeersStorage::Memory(ref mem) =>
+		match self.node_store {
+			NodeStore::Memory(ref mem) =>
 				if let Some(mut peer) = mem.peer(node_id) {
 					peer.rm_addr(addr.clone())		// TODO: cloning necessary?
 				},
-			PeersStorage::Json(ref json) =>
+			NodeStore::Json(ref json) =>
 				if let Some(mut peer) = json.peer(node_id) {
 					peer.rm_addr(addr.clone())		// TODO: cloning necessary?
 				},
@@ -389,14 +384,14 @@ impl NetworkState {
 	}

 	/// Returns the known multiaddresses of a peer.
-	pub fn addrs_of_peer(&self, node_id: &PeerstorePeerId) -> Vec<Multiaddr> {
-		match self.peerstore {
-			PeersStorage::Memory(ref mem) =>
+	pub fn addrs_of_peer(&self, node_id: &PeerId) -> Vec<Multiaddr> {
+		match self.node_store {
+			NodeStore::Memory(ref mem) =>
 				mem.peer(node_id)
 					.into_iter()
 					.flat_map(|p| p.addrs())
 					.collect::<Vec<_>>(),
-			PeersStorage::Json(ref json) =>
+			NodeStore::Json(ref json) =>
 				json.peer(node_id)
 					.into_iter()
 					.flat_map(|p| p.addrs())
@@ -407,35 +402,35 @@ impl NetworkState {
 	/// Sets information about a peer.
 	pub fn set_peer_info(
 		&self,
-		node_id: PeerstorePeerId,
+		node_id: PeerId,
 		endpoint: Endpoint,
 		client_version: String,
 		local_addr: Multiaddr,
 		remote_addr: Multiaddr
-	) -> Result<PeerId, IoError> {
+	) -> Result<NodeIndex, IoError> {
 		let mut connections = self.connections.write();
-		let peer_id = accept_connection(&mut connections, &self.next_peer_id,
+		let who = accept_connection(&mut connections, &self.next_node_index,
 			node_id.clone(), endpoint)?;
-		let infos = connections.info_by_peer.get_mut(&peer_id)
+		let infos = connections.info_by_peer.get_mut(&who)
 			.expect("Newly-created peer id is always valid");

 		infos.client_version = Some(client_version);
 		infos.remote_address = Some(remote_addr);
 		infos.local_address = Some(local_addr);

-		Ok(peer_id)
+		Ok(who)
 	}

 	/// Adds a peer to the internal peer store.
 	/// Returns an error if the peer address is invalid.
-	pub fn add_peer(&self, peer: &str) -> Result<PeerstorePeerId, Error> {
-		parse_and_add_to_peerstore(peer, &self.peerstore)
+	pub fn add_peer(&self, peer: &str) -> Result<PeerId, Error> {
+		parse_and_add_to_node_store(peer, &self.node_store)
 	}

 	/// Adds a reserved peer to the list of reserved peers.
 	/// Returns an error if the peer address is invalid.
 	pub fn add_reserved_peer(&self, peer: &str) -> Result<(), Error> {
-		let id = parse_and_add_to_peerstore(peer, &self.peerstore)?;
+		let id = parse_and_add_to_node_store(peer, &self.node_store)?;
 		self.reserved_peers.write().insert(id);
 		Ok(())
 	}
@@ -444,14 +439,14 @@ impl NetworkState {
 	/// active connection to this peer.
 	/// Returns an error if the peer address is invalid.
 	pub fn remove_reserved_peer(&self, peer: &str) -> Result<(), Error> {
-		let id = parse_and_add_to_peerstore(peer, &self.peerstore)?;
+		let id = parse_and_add_to_node_store(peer, &self.node_store)?;
 		self.reserved_peers.write().remove(&id);

 		// Dropping the peer if we're in reserved mode.
 		if self.reserved_only.load(atomic::Ordering::SeqCst) {
 			let mut connections = self.connections.write();
-			if let Some(peer_id) = connections.peer_by_nodeid.remove(&id) {
-				connections.info_by_peer.remove(&peer_id);
+			if let Some(who) = connections.peer_by_nodeid.remove(&id) {
+				connections.info_by_peer.remove(&who);
 			}
 		}

@@ -486,7 +481,7 @@ impl NetworkState {
 	}

 	/// Returns true if we are connected to the given node.
-	pub fn has_connection(&self, node_id: &PeerstorePeerId) -> bool {
+	pub fn has_connection(&self, node_id: &PeerId) -> bool {
 		let connections = self.connections.read();
 		connections.peer_by_nodeid.contains_key(node_id)
 	}
@@ -494,56 +489,56 @@ impl NetworkState {
 	/// Obtains the `UniqueConnec` corresponding to the Kademlia connection to a peer.
 	pub fn kad_connection(
 		&self,
-		node_id: PeerstorePeerId
-	) -> Result<(PeerId, UniqueConnec<KadConnecController>), IoError> {
+		node_id: PeerId
+	) -> Result<(NodeIndex, UniqueConnec<KadConnecController>), IoError> {
 		// TODO: check that the peer is disabled? should disabling a peer also prevent
 		//		 kad from working?
 		let mut connections = self.connections.write();
-		let peer_id = accept_connection(&mut connections, &self.next_peer_id,
+		let who = accept_connection(&mut connections, &self.next_node_index,
 			node_id, Endpoint::Listener)?;
-		let infos = connections.info_by_peer.get_mut(&peer_id)
+		let infos = connections.info_by_peer.get_mut(&who)
 			.expect("Newly-created peer id is always valid");
 		let connec = infos.kad_connec.clone();
-		Ok((peer_id, connec))
+		Ok((who, connec))
 	}

 	/// Obtains the `UniqueConnec` corresponding to the Ping connection to a peer.
 	pub fn ping_connection(
 		&self,
-		node_id: PeerstorePeerId
-	) -> Result<(PeerId, UniqueConnec<Pinger>), IoError> {
+		node_id: PeerId
+	) -> Result<(NodeIndex, UniqueConnec<Pinger>), IoError> {
 		let mut connections = self.connections.write();
-		let peer_id = accept_connection(&mut connections, &self.next_peer_id,
+		let who = accept_connection(&mut connections, &self.next_node_index,
 			node_id, Endpoint::Listener)?;
-		let infos = connections.info_by_peer.get_mut(&peer_id)
+		let infos = connections.info_by_peer.get_mut(&who)
 			.expect("Newly-created peer id is always valid");
 		let connec = infos.ping_connec.clone();
-		Ok((peer_id, connec))
+		Ok((who, connec))
 	}

 	/// Cleans up inactive connections and returns a list of
 	/// connections to ping.
 	pub fn cleanup_and_prepare_ping(
 		&self
-	) -> Vec<(PeerId, PeerstorePeerId, UniqueConnec<Pinger>)> {
+	) -> Vec<(NodeIndex, PeerId, UniqueConnec<Pinger>)> {
 		let mut connections = self.connections.write();
 		let connections = &mut *connections;
 		let peer_by_nodeid = &mut connections.peer_by_nodeid;
 		let info_by_peer = &mut connections.info_by_peer;

 		let mut ret = Vec::with_capacity(info_by_peer.len());
-		info_by_peer.retain(|&peer_id, infos| {
+		info_by_peer.retain(|&who, infos| {
 			// Remove the peer if neither Kad nor any protocol is alive.
 			if !infos.kad_connec.is_alive() &&
 				!infos.protocols.iter().any(|(_, conn)| conn.is_alive())
 			{
 				peer_by_nodeid.remove(&infos.id);
 				trace!(target: "sub-libp2p", "Cleaning up expired peer \
-					#{:?} ({:?})", peer_id, infos.id);
+					#{:?} ({:?})", who, infos.id);
 				return false;
 			}

-			ret.push((peer_id, infos.id.clone(), infos.ping_connec.clone()));
+			ret.push((who, infos.id.clone(), infos.ping_connec.clone()));
 			true
 		});
 		ret
@@ -551,8 +546,8 @@ impl NetworkState {

 	/// Try to add a new connection to a node in the list.
 	///
-	/// Returns a `PeerId` to allow further interfacing with this connection.
-	/// Note that all `PeerId`s are unique and never reused.
+	/// Returns a `NodeIndex` to allow further interfacing with this connection.
+	/// Note that all `NodeIndex`s are unique and never reused.
 	///
 	/// Can return an error if we are refusing the connection to the remote.
 	///
@@ -563,25 +558,23 @@ impl NetworkState {
 	/// so by dropping this sender.
 	pub fn custom_proto(
 		&self,
-		node_id: PeerstorePeerId,
+		node_id: PeerId,
 		protocol_id: ProtocolId,
 		endpoint: Endpoint,
-	) -> Result<(PeerId, UniqueConnec<(mpsc::UnboundedSender<Bytes>, u8)>), IoError> {
+	) -> Result<(NodeIndex, UniqueConnec<(mpsc::UnboundedSender<Bytes>, u8)>), IoError> {
 		let mut connections = self.connections.write();

-		if is_peer_disabled(&self.disabled_peers, &node_id) {
-			debug!(target: "sub-libp2p", "Refusing node {:?} because it was \
-				disabled", node_id);
-			return Err(IoError::new(IoErrorKind::PermissionDenied,
-				"disabled peer"))
+		if is_peer_disabled(&self.disabled_nodes, &node_id) {
+			debug!(target: "sub-libp2p", "Refusing node {:?} because it was disabled", node_id);
+			return Err(IoError::new(IoErrorKind::PermissionDenied, "disabled peer"))
 		}

-		let peer_id = accept_connection(&mut connections, &self.next_peer_id,
+		let who = accept_connection(&mut connections, &self.next_node_index,
 			node_id.clone(), endpoint)?;

 		let num_open_connections = num_open_custom_connections(&connections);

-		let infos = connections.info_by_peer.get_mut(&peer_id)
+		let infos = connections.info_by_peer.get_mut(&who)
 			.expect("Newly-created peer id is always valid");

 		let node_is_reserved = self.reserved_peers.read().contains(&infos.id);
@@ -589,27 +582,24 @@ impl NetworkState {
 			if self.reserved_only.load(atomic::Ordering::Relaxed) ||
 				num_open_connections >= self.max_peers
 			{
-				debug!(target: "sub-libp2p", "Refusing node {:?} because we \
-					reached the max number of peers", node_id);
-				return Err(IoError::new(IoErrorKind::PermissionDenied,
-					"maximum number of peers reached"))
+				debug!(target: "sub-libp2p", "Refusing node {:?} because we reached the max number of peers", node_id);
+				return Err(IoError::new(IoErrorKind::PermissionDenied, "maximum number of peers reached"))
 			}
 		}

 		if let Some((_, ref uconn)) = infos.protocols.iter().find(|&(prot, _)| prot == &protocol_id) {
-			return Ok((peer_id, uconn.clone()))
+			return Ok((who, uconn.clone()))
 		}

 		let unique_connec = UniqueConnec::empty();
 		infos.protocols.push((protocol_id.clone(), unique_connec.clone()));
-		Ok((peer_id, unique_connec))
+		Ok((who, unique_connec))
 	}

 	/// Sends some data to the given peer, using the sender that was passed
 	/// to the `UniqueConnec` of `custom_proto`.
-	pub fn send(&self, protocol: ProtocolId, peer_id: PeerId, message: Bytes)
-		-> Result<(), Error> {
-		if let Some(peer) = self.connections.read().info_by_peer.get(&peer_id) {
+	pub fn send(&self, protocol: ProtocolId, who: NodeIndex, message: Bytes) -> Result<(), Error> {
+		if let Some(peer) = self.connections.read().info_by_peer.get(&who) {
 			let sender = peer.protocols.iter().find(|elem| elem.0 == protocol)
 				.and_then(|e| e.1.poll())
 				.map(|e| e.0);
@@ -622,37 +612,35 @@ impl NetworkState {
 				// protocol.
 				debug!(target: "sub-libp2p",
 					"Tried to send message to peer {} for which we aren't connected with the requested protocol",
-					peer_id
+					who
 				);
 				return Err(ErrorKind::PeerNotFound.into())
 			}
 		} else {
-			debug!(target: "sub-libp2p", "Tried to send message to invalid peer ID {}", peer_id);
+			debug!(target: "sub-libp2p", "Tried to send message to invalid peer ID {}", who);
 			return Err(ErrorKind::PeerNotFound.into())
 		}
 	}

 	/// Get the info on a peer, if there's an active connection.
-	pub fn peer_info(&self, who: PeerId) -> Option<PeerInfo> {
+	pub fn peer_info(&self, who: NodeIndex) -> Option<PeerInfo> {
 		self.connections.read().info_by_peer.get(&who).map(Into::into)
 	}

+	/// Reports that an attempt to make a low-level ping of the peer failed.
+	pub fn report_ping_failed(&self, who: NodeIndex) {
+		self.drop_peer(who);
+	}
+
 	/// Disconnects a peer, if a connection exists (ie. drops the Kademlia
 	/// controller, and the senders that were stored in the `UniqueConnec` of
 	/// `custom_proto`).
-	pub fn drop_peer(&self, peer_id: PeerId, reason: Option<&str>) {
+	pub fn drop_peer(&self, who: NodeIndex) {
 		let mut connections = self.connections.write();
-		if let Some(peer_info) = connections.info_by_peer.remove(&peer_id) {
-			if let Some(reason) = reason {
-				if let (&Some(ref client_version), &Some(ref remote_address)) = (&peer_info.client_version, &peer_info.remote_address) {
-					debug!(target: "sub-libp2p", "Disconnected peer {} (version: {}, address: {}). {}", peer_id, client_version, remote_address, reason);
-				} else {
-					debug!(target: "sub-libp2p", "Disconnected peer {}. {}", peer_id, reason);
-				}
-			}
-
-			trace!(target: "sub-libp2p", "Destroying peer #{} {:?} ; \
-				kademlia = {:?} ; num_protos = {:?}", peer_id, peer_info.id,
+		if let Some(peer_info) = connections.info_by_peer.remove(&who) {
+			trace!(target: "sub-libp2p", "Destroying peer #{} {:?} ; kademlia = {:?} ; num_protos = {:?}",
+				who,
+				peer_info.id,
 				peer_info.kad_connec.is_alive(),
 				peer_info.protocols.iter().filter(|c| c.1.is_alive()).count());
 			// TODO: we manually clear the connections as a work-around for
@@ -660,7 +648,7 @@ impl NetworkState {
 			for c in peer_info.protocols.iter() { c.1.clear(); }
 			peer_info.kad_connec.clear();
 			let old = connections.peer_by_nodeid.remove(&peer_info.id);
-			debug_assert_eq!(old, Some(peer_id));
+			debug_assert_eq!(old, Some(who));
 		}
 	}

@@ -681,18 +669,18 @@ impl NetworkState {
 	/// list of disabled peers, and  drops any existing connections if
 	/// necessary (ie. drops the sender that was stored in the `UniqueConnec`
 	/// of `custom_proto`).
-	pub fn disable_peer(&self, peer_id: PeerId, reason: &str) {
+	pub fn ban_peer(&self, who: NodeIndex, reason: &str) {
 		// TODO: what do we do if the peer is reserved?
 		// TODO: same logging as in disconnect_peer
 		let mut connections = self.connections.write();
-		let peer_info = if let Some(peer_info) = connections.info_by_peer.remove(&peer_id) {
+		let peer_info = if let Some(peer_info) = connections.info_by_peer.remove(&who) {
 			if let (&Some(ref client_version), &Some(ref remote_address)) = (&peer_info.client_version, &peer_info.remote_address) {
-				info!(target: "network", "Peer {} (version: {}, address: {}) disabled. {}", peer_id, client_version, remote_address, reason);
+				info!(target: "network", "Peer {} (version: {}, address: {}) disabled. {}", who, client_version, remote_address, reason);
 			} else {
-				info!(target: "network", "Peer {} disabled. {}", peer_id, reason);
+				info!(target: "network", "Peer {} disabled. {}", who, reason);
 			}
 			let old = connections.peer_by_nodeid.remove(&peer_info.id);
-			debug_assert_eq!(old, Some(peer_id));
+			debug_assert_eq!(old, Some(who));
 			peer_info
 		} else {
 			return
@@ -700,7 +688,7 @@ impl NetworkState {

 		drop(connections);
 		let timeout = Instant::now() + PEER_DISABLE_DURATION;
-		self.disabled_peers.lock().insert(peer_info.id.clone(), timeout);
+		self.disabled_nodes.lock().insert(peer_info.id.clone(), timeout);
 	}

 	/// Flushes the caches to the disk.
@@ -708,18 +696,16 @@ impl NetworkState {
 	/// This is done in an atomical way, so that an error doesn't corrupt
 	/// anything.
 	pub fn flush_caches_to_disk(&self) -> Result<(), IoError> {
-		match self.peerstore {
-			PeersStorage::Memory(_) => Ok(()),
-			PeersStorage::Json(ref json) =>
+		match self.node_store {
+			NodeStore::Memory(_) => Ok(()),
+			NodeStore::Json(ref json) =>
 				match json.flush() {
 					Ok(()) => {
-						debug!(target: "sub-libp2p", "Flushed JSON peer store \
-							to disk");
+						debug!(target: "sub-libp2p", "Flushed JSON peer store to disk");
 						Ok(())
 					}
 					Err(err) => {
-						warn!(target: "sub-libp2p", "Failed to flush changes \
-							to JSON peer store: {}", err);
+						warn!(target: "sub-libp2p", "Failed to flush changes to JSON peer store: {}", err);
 						Err(err)
 					}
 				}
@@ -733,23 +719,22 @@ impl Drop for NetworkState {
 	}
 }

-/// Assigns a `PeerId` to a node, or returns an existing ID if any exists.
+/// Assigns a `NodeIndex` to a node, or returns an existing ID if any exists.
 ///
 /// The function only accepts already-locked structs, so that we don't risk
 /// any deadlock.
 fn accept_connection(
 	connections: &mut Connections,
-	next_peer_id: &atomic::AtomicUsize,
-	node_id: PeerstorePeerId,
+	next_node_index: &atomic::AtomicUsize,
+	node_id: PeerId,
 	endpoint: Endpoint
-) -> Result<PeerId, IoError> {
+) -> Result<NodeIndex, IoError> {
 	let peer_by_nodeid = &mut connections.peer_by_nodeid;
 	let info_by_peer = &mut connections.info_by_peer;

-	let peer_id = *peer_by_nodeid.entry(node_id.clone()).or_insert_with(|| {
-		let new_id = next_peer_id.fetch_add(1, atomic::Ordering::Relaxed);
-		trace!(target: "sub-libp2p", "Creating new peer #{:?} for {:?}",
-			new_id, node_id);
+	let who = *peer_by_nodeid.entry(node_id.clone()).or_insert_with(|| {
+		let new_id = next_node_index.fetch_add(1, atomic::Ordering::Relaxed);
+		trace!(target: "sub-libp2p", "Creating new peer #{:?} for {:?}", new_id, node_id);

 		info_by_peer.insert(new_id, PeerConnectionInfo {
 			protocols: Vec::new(),    // TODO: Vec::with_capacity(num_registered_protocols),
@@ -765,13 +750,13 @@ fn accept_connection(
 		new_id
 	});

-	Ok(peer_id)
+	Ok(who)
 }

 /// Returns true if a peer is disabled.
 fn is_peer_disabled(
-	list: &Mutex<FnvHashMap<PeerstorePeerId, Instant>>,
-	peer: &PeerstorePeerId
+	list: &Mutex<FnvHashMap<PeerId, Instant>>,
+	peer: &PeerId
 ) -> bool {
 	let mut list = list.lock();
 	if let Some(timeout) = list.get(peer).cloned() {
@@ -804,30 +789,32 @@ fn num_open_custom_connections(connections: &Connections) -> u32 {
 }

 /// Parses an address of the form `/ip4/x.x.x.x/tcp/x/p2p/xxxxxx`, and adds it
-/// to the given peerstore. Returns the corresponding peer ID.
-fn parse_and_add_to_peerstore(addr_str: &str, peerstore: &PeersStorage)
-	-> Result<PeerstorePeerId, Error> {
+/// to the given node_store. Returns the corresponding peer ID.
+fn parse_and_add_to_node_store(
+	addr_str: &str,
+	node_store: &NodeStore
+) -> Result<PeerId, Error> {

 	let mut addr = addr_str.to_multiaddr().map_err(|_| ErrorKind::AddressParse)?;
-	let peer_id = match addr.pop() {
+	let who = match addr.pop() {
 		Some(AddrComponent::P2P(key)) | Some(AddrComponent::IPFS(key)) =>
-			PeerstorePeerId::from_bytes(key).map_err(|_| ErrorKind::AddressParse)?,
+			PeerId::from_bytes(key).map_err(|_| ErrorKind::AddressParse)?,
 		_ => return Err(ErrorKind::AddressParse.into()),
 	};

 	// Registering the bootstrap node with a TTL of 100000 years   TODO: wrong
-	match peerstore {
-		PeersStorage::Memory(ref peerstore) =>
-			peerstore
-				.peer_or_create(&peer_id)
+	match node_store {
+		NodeStore::Memory(ref node_store) =>
+			node_store
+				.peer_or_create(&who)
 				.add_addr(addr, Duration::from_secs(100000 * 365 * 24 * 3600)),
-		PeersStorage::Json(ref peerstore) =>
-			peerstore
-				.peer_or_create(&peer_id)
+		NodeStore::Json(ref node_store) =>
+			node_store
+				.peer_or_create(&who)
 				.add_addr(addr, Duration::from_secs(100000 * 365 * 24 * 3600)),
 	}
 	
-	Ok(peer_id)
+	Ok(who)
 }

 /// Obtains or generates the local private key using the configuration.
@@ -848,9 +835,11 @@ fn obtain_private_key(config: &NetworkConfiguration)
 				Ok(s) => Ok(s),
 				Err(err) => {
 					// Failed to fetch existing file ; generate a new key
-					trace!(target: "sub-libp2p", "Failed to load existing \
-						secret key file {:?},  generating new key ; err = {:?}",
-						secret_path, err);
+					trace!(target: "sub-libp2p",
+						"Failed to load existing secret key file {:?},  generating new key ; err = {:?}",
+						secret_path,
+						err
+					);
 					Ok(gen_key_and_try_write_to_file(&secret_path))
 				}
 			}
@@ -861,8 +850,7 @@ fn obtain_private_key(config: &NetworkConfiguration)
 			let mut key: [u8; 32] = [0; 32];
 			rand::rngs::EntropyRng::new().fill(&mut key);
 			Ok(secio::SecioKeyPair::secp256k1_raw_key(&key)
-				.expect("randomly-generated key with correct len should \
-					always be valid"))
+				.expect("randomly-generated key with correct len should always be valid"))
 		}
 	}
 }
@@ -899,12 +887,17 @@ fn gen_key_and_try_write_to_file<P>(path: P) -> secio::SecioKeyPair
 		Ok(mut file) =>
 			match file.write_all(&raw_key) {
 				Ok(()) => (),
-				Err(err) => warn!(target: "sub-libp2p", "Failed to write \
-					secret key in file {:?} ; err = {:?}", path.as_ref(), err),
+				Err(err) => warn!(target: "sub-libp2p",
+					"Failed to write secret key in file {:?} ; err = {:?}",
+					path.as_ref(),
+					err
+				),
 			},
-		Err(err) =>
-			warn!(target: "sub-libp2p", "Failed to store secret key in file \
-				{:?} ; err = {:?}", path.as_ref(), err),
+		Err(err) => warn!(target: "sub-libp2p",
+			"Failed to store secret key in file {:?} ; err = {:?}",
+			path.as_ref(),
+			err
+		),
 	}

 	secio_key
@@ -943,13 +936,13 @@ mod tests {
 		let state = NetworkState::new(&Default::default()).unwrap();
 		let example_peer = PublicKey::Rsa(vec![1, 2, 3, 4]).into_peer_id();

-		let (peer_id, _) = state.custom_proto(
+		let (who, _) = state.custom_proto(
 			example_peer.clone(),
 			[1, 2, 3],
 			Endpoint::Dialer
 		).unwrap();

-		state.disable_peer(peer_id, "Just a test");
+		state.ban_peer(who, "Just a test");

 		assert!(state.custom_proto(
 			example_peer.clone(),
@@ -16,7 +16,7 @@

 use bytes::Bytes;
 use {Error, ErrorKind, NetworkConfiguration, NetworkProtocolHandler};
-use {NonReservedPeerMode, NetworkContext, Severity, PeerId, ProtocolId};
+use {NonReservedPeerMode, NetworkContext, Severity, NodeIndex, ProtocolId};
 use parking_lot::{Mutex, RwLock};
 use libp2p;
 use libp2p::multiaddr::{AddrComponent, Multiaddr};
@@ -77,7 +77,7 @@ struct Shared {
 	kad_upgrade: KadConnecConfig,

 	/// List of protocols available on the network. It is a logic error to
-	/// remote protocols from this list, and the code may assume that protocols
+	/// remove protocols from this list, and the code may assume that protocols
 	/// stay at the same index forever.
 	protocols: RwLock<RegisteredProtocols<Arc<NetworkProtocolHandler + Send + Sync>>>,

@@ -149,8 +149,7 @@ impl NetworkService {
 		// reach us
 		self.shared.original_listened_addr.read().as_ref()
 			.map(|addr|
-				format!("{}/p2p/{}", addr,
-					self.shared.kad_system.local_peer_id().to_base58())
+				format!("{}/p2p/{}", addr, self.shared.kad_system.local_peer_id().to_base58())
 			)
 	}

@@ -204,8 +203,7 @@ impl NetworkService {
 			let fut = match init_thread(core.handle(), shared,
 				timeouts_register_rx, close_rx) {
 				Ok(future) => {
-					debug!(target: "sub-libp2p", "Successfully started \
-						networking service");
+					debug!(target: "sub-libp2p", "Successfully started networking service");
 					let _ = init_tx.send(Ok(()));
 					future
 				},
@@ -217,8 +215,7 @@ impl NetworkService {

 			match core.run(fut) {
 				Ok(()) => debug!(target: "sub-libp2p", "libp2p future finished"),
-				Err(err) => error!(target: "sub-libp2p", "error while running \
-					libp2p: {:?}", err),
+				Err(err) => error!(target: "sub-libp2p", "error while running libp2p: {:?}", err),
 			}
 		});

@@ -234,8 +231,7 @@ impl NetworkService {
 		if let Some((close_tx, join)) = self.bg_thread.lock().take() {
 			let _ = close_tx.send(());
 			if let Err(e) = join.join() {
-				warn!(target: "sub-libp2p", "error while waiting on libp2p \
-					background thread: {:?}", e);
+				warn!(target: "sub-libp2p", "error while waiting on libp2p background thread: {:?}", e);
 			}
 		}

@@ -243,7 +239,7 @@ impl NetworkService {
 	}

 	/// Get a list of all connected peers by id.
-	pub fn connected_peers(&self) -> Vec<PeerId> {
+	pub fn connected_peers(&self) -> Vec<NodeIndex> {
 		self.shared.network_state.connected_peers()
 	}

@@ -295,18 +291,18 @@ impl Drop for NetworkService {
 struct NetworkContextImpl {
 	inner: Arc<Shared>,
 	protocol: ProtocolId,
-	current_peer: Option<PeerId>,
+	current_peer: Option<NodeIndex>,
 }

 impl NetworkContext for NetworkContextImpl {
-	fn send(&self, peer: PeerId, packet_id: PacketId, data: Vec<u8>) {
+	fn send(&self, peer: NodeIndex, packet_id: PacketId, data: Vec<u8>) {
 		self.send_protocol(self.protocol, peer, packet_id, data)
 	}

 	fn send_protocol(
 		&self,
 		protocol: ProtocolId,
-		peer: PeerId,
+		peer: NodeIndex,
 		packet_id: PacketId,
 		data: Vec<u8>
 	) {
@@ -318,7 +314,8 @@ impl NetworkContext for NetworkContextImpl {
 		message.extend_from_slice(&[packet_id]);
 		message.extend_from_slice(&data);
 		if self.inner.network_state.send(protocol, peer, message).is_err() {
-			self.inner.network_state.drop_peer(peer, Some("Sending to peer failed"));
+			debug!(target: "sub-libp2p", "Sending to peer {} failed. Dropping.", peer);
+			self.inner.network_state.drop_peer(peer);
 		}
 	}

@@ -330,18 +327,24 @@ impl NetworkContext for NetworkContextImpl {
 		}
 	}

-	fn report_peer(&self, peer: PeerId, reason: Severity) {
+	fn report_peer(&self, peer: NodeIndex, reason: Severity) {
 		if let Some(info) = self.inner.network_state.peer_info(peer) {
 			if let (Some(client_version), Some(remote_address)) = (info.client_version, info.remote_address) {
-				info!(target: "sub-libp2p", "Peer {} ({} {}) reported by client: {}", peer, remote_address, client_version, reason);
+				info!(target: "sub-libp2p",
+					"Peer {} ({} {}) reported by client: {}",
+					peer,
+					remote_address,
+					client_version,
+					reason
+				);
 			} else {
 				info!(target: "sub-libp2p", "Peer {} reported by client: {}", peer, reason);
 			}
 		}
 		match reason {
-			Severity::Bad(reason) => self.inner.network_state.disable_peer(peer, reason),
-			Severity::Useless(reason) => self.inner.network_state.drop_peer(peer, Some(reason)),
-			Severity::Timeout => self.inner.network_state.drop_peer(peer, Some("Timeout waiting for response")),
+			Severity::Bad(reason) => self.inner.network_state.ban_peer(peer, reason),
+			Severity::Useless(_) => self.inner.network_state.drop_peer(peer),
+			Severity::Timeout => self.inner.network_state.drop_peer(peer),
 		}
 	}

@@ -368,17 +371,17 @@ impl NetworkContext for NetworkContextImpl {
 		Ok(())
 	}

-	fn peer_client_version(&self, peer: PeerId) -> String {
+	fn peer_client_version(&self, peer: NodeIndex) -> String {
 		// Devp2p returns "unknown" on unknown peer ID, so we do the same.
 		self.inner.network_state.peer_client_version(peer, self.protocol)
 			.unwrap_or_else(|| "unknown".to_string())
 	}

-	fn session_info(&self, peer: PeerId) -> Option<SessionInfo> {
+	fn session_info(&self, peer: NodeIndex) -> Option<SessionInfo> {
 		self.inner.network_state.session_info(peer, self.protocol)
 	}

-	fn protocol_version(&self, protocol: ProtocolId, peer: PeerId) -> Option<u8> {
+	fn protocol_version(&self, protocol: ProtocolId, peer: NodeIndex) -> Option<u8> {
 		self.inner.network_state.protocol_version(peer, protocol)
 	}

@@ -394,7 +397,9 @@ impl NetworkContext for NetworkContextImpl {
 fn init_thread(
 	core: Handle,
 	shared: Arc<Shared>,
-	timeouts_register_rx: mpsc::UnboundedReceiver<(Duration, (Arc<NetworkProtocolHandler + Send + Sync + 'static>, ProtocolId, TimerToken))>,
+	timeouts_register_rx: mpsc::UnboundedReceiver<
+		(Duration, (Arc<NetworkProtocolHandler + Send + Sync + 'static>, ProtocolId, TimerToken))
+	>,
 	close_rx: oneshot::Receiver<()>
 ) -> Result<impl Future<Item = (), Error = IoError>, Error> {
 	// Build the transport layer.
@@ -407,11 +412,10 @@ fn init_thread(

 		let addr_resolver = {
 			let shared = shared.clone();
-			move |peer_id| {
-				let addrs = shared.network_state.addrs_of_peer(&peer_id);
+			move |who| {
+				let addrs = shared.network_state.addrs_of_peer(&who);
 				for addr in &addrs {
-					trace!(target: "sub-libp2p", "{:?} resolved as {}",
-						peer_id, addr);
+					trace!(target: "sub-libp2p", "{:?} resolved as {}", who, addr);
 				}
 				addrs.into_iter()
 			}
@@ -473,8 +477,7 @@ fn init_thread(
 				*shared.original_listened_addr.write() = Some(new_addr.clone());
 			},
 			Err(_) => {
-				warn!(target: "sub-libp2p", "Can't listen on {}, protocol not \
-					supported", listen_addr);
+				warn!(target: "sub-libp2p", "Can't listen on {}, protocol not supported", listen_addr);
 				return Err(ErrorKind::BadProtocol.into())
 			},
 		}
@@ -482,14 +485,14 @@ fn init_thread(
 	// Explicitely connect to _all_ the boostrap nodes as a temporary measure.
 	for bootnode in shared.config.boot_nodes.iter() {
 		match shared.network_state.add_peer(bootnode) {
-			Ok(peer_id) => {
-				trace!(target: "sub-libp2p", "Dialing bootnode {:?}", peer_id);
+			Ok(who) => {
+				trace!(target: "sub-libp2p", "Dialing bootnode {:?}", who);
 				for proto in shared.protocols.read().0.clone().into_iter() {
 					open_peer_custom_proto(
 						shared.clone(),
 						transport.clone(),
 						proto,
-						peer_id.clone(),
+						who.clone(),
 						&swarm_controller
 					)
 				}
@@ -508,7 +511,7 @@ fn init_thread(
 				};

 				if let Ok(addr) = multi {
-					trace!(target: "sub-libp2p", "Missing PeerId for Bootnode {:}. Querying", bootnode);
+					trace!(target: "sub-libp2p", "Missing NodeIndex for Bootnode {:}. Querying", bootnode);
 					for proto in shared.protocols.read().0.clone().into_iter() {
 						connect_with_query_peer_id(
 							shared.clone(),
@@ -520,7 +523,7 @@ fn init_thread(
 					}
 				} else {
 					warn!(target: "sub-libp2p", "Not a valid Bootnode Address {:}", bootnode);
-						continue;
+					continue;
 				}
 			},
 			Err(err) => warn!(target:"sub-libp2p", "Couldn't parse Bootnode Address: {}", err),
@@ -560,8 +563,7 @@ fn init_thread(
 		.select(close_rx.then(|_| Ok(()))).map(|_| ()).map_err(|(err, _)| err)

 		.and_then(move |_| {
-			debug!(target: "sub-libp2p", "Networking ended ; disconnecting \
-				all peers");
+			debug!(target: "sub-libp2p", "Networking ended ; disconnecting all peers");
 			shared.network_state.disconnect_all();
 			Ok(())
 		}))
@@ -593,8 +595,7 @@ fn listener_handle<'a, C>(
 	where C: AsyncRead + AsyncWrite + 'a {
 	match upgrade {
 		FinalUpgrade::Kad(controller, kademlia_stream, client_addr) => {
-			trace!(target: "sub-libp2p", "Opened kademlia substream with {:?}",
-				client_addr);
+			trace!(target: "sub-libp2p", "Opened kademlia substream with {:?}", client_addr);
 			match handle_kademlia_connection(shared, client_addr, controller, kademlia_stream) {
 				Ok(fut) => Box::new(fut) as Box<_>,
 				Err(err) => Box::new(future::err(err)) as Box<_>,
@@ -624,8 +625,7 @@ fn listener_handle<'a, C>(
 			let node_id = p2p_multiaddr_to_node_id(client_addr);
 			match shared.network_state.ping_connection(node_id.clone()) {
 				Ok((_, ping_connec)) => {
-					trace!(target: "sub-libp2p", "Successfully opened ping \
-						substream with {:?}", node_id);
+					trace!(target: "sub-libp2p", "Successfully opened ping substream with {:?}", node_id);
 					let fut = ping_connec.set_until(pinger, future);
 					Box::new(fut) as Box<_>
 				},
@@ -650,7 +650,7 @@ fn handle_kademlia_connection(
 	kademlia_stream: Box<Stream<Item = KadIncomingRequest, Error = IoError>>
 ) -> Result<impl Future<Item = (), Error = IoError>, IoError> {
 	let node_id = p2p_multiaddr_to_node_id(client_addr);
-	let (peer_id, kad_connec) = shared.network_state
+	let (who, kad_connec) = shared.network_state
 		.kad_connection(node_id.clone())?;
 	
 	let node_id2 = node_id.clone();
@@ -679,8 +679,7 @@ fn handle_kademlia_connection(
 				Ok(future::Loop::Continue(rest))
 			})
 	}).then(move |val| {
-		trace!(target: "sub-libp2p", "Closed Kademlia connection \
-			with #{} {:?} => {:?}", peer_id, node_id2, val);
+		trace!(target: "sub-libp2p", "Closed Kademlia connection with #{} {:?} => {:?}", who, node_id2, val);
 		val
 	});

@@ -695,16 +694,16 @@ fn build_kademlia_response(
 ) -> Vec<KadPeer> {
 	shared.kad_system
 		.known_closest_peers(searched)
-		.map(move |peer_id| {
-			if peer_id == *shared.kad_system.local_peer_id() {
+		.map(move |who| {
+			if who == *shared.kad_system.local_peer_id() {
 				KadPeer {
-					node_id: peer_id.clone(),
+					node_id: who.clone(),
 					multiaddrs: shared.listened_addrs.read().clone(),
 					connection_ty: KadConnectionType::Connected,
 				}
 			} else {
-				let addrs = shared.network_state.addrs_of_peer(&peer_id);
-				let connec_ty = if shared.network_state.has_connection(&peer_id) {
+				let addrs = shared.network_state.addrs_of_peer(&who);
+				let connec_ty = if shared.network_state.has_connection(&who) {
 					// TODO: this only checks connections with substrate ; but what
 					//       if we're connected through Kademlia only?
 					KadConnectionType::Connected
@@ -713,7 +712,7 @@ fn build_kademlia_response(
 				};

 				KadPeer {
-					node_id: peer_id.clone(),
+					node_id: who.clone(),
 					multiaddrs: addrs,
 					connection_ty: connec_ty,
 				}
@@ -749,7 +748,7 @@ fn handle_custom_connection(
 	// TODO: is there a better way to refuse connections than to drop the
 	//		 newly-opened substream? should we refuse the connection
 	//		 beforehand?
-	let (peer_id, unique_connec) = match shared.network_state.custom_proto(
+	let (who, unique_connec) = match shared.network_state.custom_proto(
 		node_id.clone(),
 		protocol_id,
 		custom_proto_out.endpoint,
@@ -759,14 +758,17 @@ fn handle_custom_connection(
 	};

 	if let UniqueConnecState::Full = unique_connec.state() {
-		debug!(target: "sub-libp2p", "Interrupting connection attempt to {:?} \
-			with {:?} because we're already connected", node_id, custom_proto_out.protocol_id);
+		debug!(target: "sub-libp2p",
+			"Interrupting connection attempt to {:?} with {:?} because we're already connected",
+			node_id,
+			custom_proto_out.protocol_id
+		);
 		return future::Either::A(future::ok(()))
 	}

 	struct ProtoDisconnectGuard {
 		inner: Arc<Shared>,
-		peer_id: PeerId,
+		who: NodeIndex,
 		node_id: PeerstorePeerId,
 		handler: Arc<NetworkProtocolHandler + Send + Sync>,
 		protocol: ProtocolId
@@ -774,27 +776,27 @@ fn handle_custom_connection(

 	impl Drop for ProtoDisconnectGuard {
 		fn drop(&mut self) {
-			debug!(target: "sub-libp2p",
+			info!(target: "sub-libp2p",
 				"Node {:?} with peer ID {} through protocol {:?} disconnected",
 				self.node_id,
-				self.peer_id,
+				self.who,
 				self.protocol
 			);
 			self.handler.disconnected(&NetworkContextImpl {
 				inner: self.inner.clone(),
 				protocol: self.protocol,
-				current_peer: Some(self.peer_id),
-			}, &self.peer_id);
+				current_peer: Some(self.who),
+			}, &self.who);

 			// When any custom protocol drops, we drop the peer entirely.
 			// TODO: is this correct?
-			self.inner.network_state.drop_peer(self.peer_id, Some("Remote end disconnected"));
+			self.inner.network_state.drop_peer(self.who);
 		}
 	}

 	let dc_guard = ProtoDisconnectGuard {
 		inner: shared.clone(),
-		peer_id,
+		who,
 		node_id: node_id.clone(),
 		handler: handler.clone(),
 		protocol: protocol_id,
@@ -810,8 +812,8 @@ fn handle_custom_connection(
 				handler.read(&NetworkContextImpl {
 					inner: shared.clone(),
 					protocol: protocol_id,
-					current_peer: Some(peer_id.clone()),
-				}, &peer_id, packet_id, &data);
+					current_peer: Some(who.clone()),
+				}, &who, packet_id, &data);
 				Ok(())
 			}
 		});
@@ -824,15 +826,19 @@ fn handle_custom_connection(
 			val
 		});

-	debug!(target: "sub-libp2p", "Successfully connected to {:?} (peer id \
-		{}) with protocol {:?} version {}", node_id, peer_id, protocol_id,
-		custom_proto_out.protocol_version);
+	debug!(target: "sub-libp2p",
+		"Successfully connected to {:?} (peer id {}) with protocol {:?} version {}",
+		node_id,
+		who,
+		protocol_id,
+		custom_proto_out.protocol_version
+	);

 	handler.connected(&NetworkContextImpl {
 		inner: shared.clone(),
 		protocol: protocol_id,
-		current_peer: Some(peer_id),
-	}, &peer_id);
+		current_peer: Some(who),
+	}, &who);

 	future::Either::B(final_fut)
 }
@@ -869,10 +875,10 @@ fn start_kademlia_discovery<T, To, St, C>(shared: Arc<Shared>, transport: T,
 		let shared = shared.clone();
 		let transport = transport.clone();
 		let swarm_controller = swarm_controller.clone();
-		move |peer_id|
+		move |who|
 			obtain_kad_connection(
 				shared.clone(),
-				peer_id.clone(),
+				who.clone(),
 				transport.clone(),
 				swarm_controller.clone()
 			)
@@ -938,8 +944,7 @@ fn perform_kademlia_query<T, To, St, C>(
 	let random_key = PublicKey::Ed25519((0 .. 32)
 		.map(|_| -> u8 { rand::random() }).collect());
 	let random_peer_id = random_key.into_peer_id();
-	trace!(target: "sub-libp2p", "Start kademlia discovery for {:?}",
-		random_peer_id);
+	trace!(target: "sub-libp2p", "Start kademlia discovery for {:?}", random_peer_id);

 	shared.clone()
 		.kad_system
@@ -947,7 +952,7 @@ fn perform_kademlia_query<T, To, St, C>(
 			let shared = shared.clone();
 			let transport = transport.clone();
 			let swarm_controller = swarm_controller.clone();
-			move |peer_id| obtain_kad_connection(shared.clone(), peer_id.clone(),
+			move |who| obtain_kad_connection(shared.clone(), who.clone(),
 				transport.clone(), swarm_controller.clone())
 		})
 		.filter_map(move |event|
@@ -980,8 +985,10 @@ fn connect_to_nodes<T, To, St, C>(
 		St: MuxedTransport<Output = FinalUpgrade<C>> + Clone + 'static,
 		C: 'static {
 	let num_slots = shared.network_state.should_open_outgoing_custom_connections();
-	debug!(target: "sub-libp2p", "Outgoing connections cycle ; opening up to \
-		{} outgoing connections", num_slots);
+	debug!(target: "sub-libp2p",
+		"Outgoing connections cycle ; opening up to {} outgoing connections",
+		num_slots
+	);

 	for _ in 0 .. num_slots {
 		// Choose a random peer. We are potentially already connected to
@@ -1034,8 +1041,11 @@ fn connect_with_query_peer_id<T, To, St, C>(
 				.and_then(move |info| {
 					let _ = process_identify_info(shared, &info, original_addr,
 						endpoint, &base_transport);
-					trace!(target: "sub-libp2p", "Bootnode {:} found with peer id: {:?}",
-						addr2, info.info.public_key.into_peer_id());
+					trace!(target: "sub-libp2p",
+						"Bootnode {:} found with peer id: {:?}",
+						addr2,
+						info.info.public_key.into_peer_id()
+					);
 					upgrade::apply(socket, proto, endpoint, client_addr)
 				})
 		})
@@ -1050,15 +1060,19 @@ fn connect_with_query_peer_id<T, To, St, C>(
 		.map_err({
 			let addr = addr.clone();
 			move |err| {
-				warn!(target: "sub-libp2p", "Error while dialing {:?} to query peer id: {:?}",
-					addr, err);
+				warn!(target: "sub-libp2p",
+					"Error while dialing {:?} to query peer id: {:?}",
+					addr,
+					err
+				);
 				err
 			}
 		});

-    let _ = swarm_controller.dial(addr.clone(), with_err)
-        .map_err( move |err| warn!(target: "sub-libp2p",
-				"Error when querying peer node info {:} of {:}", err, addr));
+	let _ = swarm_controller.dial(addr.clone(), with_err)
+		.map_err(move |err|
+			warn!(target: "sub-libp2p", "Error when querying peer node info {:} of {:}", err, addr)
+		);
 }

 /// If necessary, dials the given address for the given protocol and using the
@@ -1081,8 +1095,7 @@ fn open_peer_custom_proto<T, To, St, C>(
 	// Don't connect to ourselves.
 	// TODO: remove this eventually
 	if &expected_peer_id == shared.kad_system.local_peer_id() {
-		trace!(target: "sub-libp2p", "Skipped connecting to {:?} because \
-			it is ourselves", expected_peer_id);
+		trace!(target: "sub-libp2p", "Skipped connecting to {:?} because it is ourselves", expected_peer_id);
 		return
 	}

@@ -1102,13 +1115,14 @@ fn open_peer_custom_proto<T, To, St, C>(
 					if info.info.public_key.into_peer_id() == expected_peer_id {
 						Ok(socket)
 					} else {
-						debug!(target: "sub-libp2p", "Public key mismatch for \
-							node {:?} with proto {:?}", expected_peer_id, proto_id);
-						trace!(target: "sub-libp2p", "Removing addr {} for {:?}",
-							original_addr, expected_peer_id);
+						debug!(target: "sub-libp2p",
+							"Public key mismatch for node {:?} with proto {:?}",
+							expected_peer_id,
+							proto_id
+						);
+						trace!(target: "sub-libp2p", "Removing addr {} for {:?}", original_addr, expected_peer_id);
 						shared.network_state.set_invalid_kad_address(&expected_peer_id, &original_addr);
-						Err(IoError::new(IoErrorKind::InvalidData, "public \
-							key mismatch when identifyed peer"))
+						Err(IoError::new(IoErrorKind::InvalidData, "public key mismatch when identifyed peer"))
 					}
 				)
 				.and_then(move |socket|
@@ -1128,32 +1142,39 @@ fn open_peer_custom_proto<T, To, St, C>(
 		.map_err({
 			let node_id = node_id.clone();
 			move |err| {
-				debug!(target: "sub-libp2p", "Error while dialing \
-					{:?} with custom proto: {:?}", node_id, err);
+				debug!(target: "sub-libp2p", "Error while dialing {:?} with custom proto: {:?}", node_id, err);
 				err
 			}
 		});

 	match shared2.network_state.custom_proto(node_id.clone(), proto_id, Endpoint::Dialer) {
-		Ok((peer_id, unique_connec)) => {
+		Ok((who, unique_connec)) => {
 			if !unique_connec.is_alive() {
-				trace!(target: "sub-libp2p", "Opening connection to #{} {:?} with \
-					proto {:?}", peer_id, node_id, proto_id);
+				trace!(target: "sub-libp2p",
+					"Opening connection to #{} {:?} with proto {:?}",
+					who,
+					node_id,
+					proto_id
+				);
 			}

 			// TODO: this future should be used
 			let _ = unique_connec.get_or_dial(&swarm_controller, &addr, with_err);
 		},
 		Err(err) => {
-			trace!(target: "sub-libp2p", "Error while opening connection to
-				{:?} with proto {:?} => {:?}", node_id, proto_id, err);
+			trace!(target: "sub-libp2p",
+				"Error while opening connection to {:?} with proto {:?} => {:?}",
+				node_id,
+				proto_id,
+				err
+			);
 		},
 	}
 }

 /// Obtain a Kademlia connection to the given peer.
 fn obtain_kad_connection<T, To, St, C>(shared: Arc<Shared>,
-	peer_id: PeerstorePeerId, transport: T, swarm_controller: SwarmController<St>)
+	who: PeerstorePeerId, transport: T, swarm_controller: SwarmController<St>)
 	-> impl Future<Item = KadConnecController, Error = IoError>
 	where T: MuxedTransport<Output =  TransportOutput<To>> + Clone + 'static,
 		T::MultiaddrFuture: 'static,
@@ -1161,7 +1182,7 @@ fn obtain_kad_connection<T, To, St, C>(shared: Arc<Shared>,
 		St: MuxedTransport<Output = FinalUpgrade<C>> + Clone + 'static,
 		C: 'static {
 	let kad_upgrade = shared.kad_upgrade.clone();
-	let addr: Multiaddr = AddrComponent::P2P(peer_id.clone().into_bytes()).into();
+	let addr: Multiaddr = AddrComponent::P2P(who.clone().into_bytes()).into();
 	let transport = transport
 		.and_then(move |out, endpoint, client_addr|
 			upgrade::apply(out.socket, kad_upgrade.clone(),
@@ -1175,7 +1196,7 @@ fn obtain_kad_connection<T, To, St, C>(shared: Arc<Shared>,
 		});
 	
 	shared.network_state
-		.kad_connection(peer_id.clone())
+		.kad_connection(who.clone())
 		.into_future()
 		.map(move |(_, k)| k.get_or_dial(&swarm_controller, &addr, transport))
 		.flatten()
@@ -1204,14 +1225,15 @@ fn process_identify_info(
 		if let Some(mut ext_addr) = transport.nat_traversal(original_listened_addr, &info.observed_addr) {
 			let mut listened_addrs = shared.listened_addrs.write();
 			if !listened_addrs.iter().any(|a| a == &ext_addr) {
-				trace!(target: "sub-libp2p", "NAT traversal: remote observes us as \
-					{} ; registering {} as one of our own addresses",
-					info.observed_addr, ext_addr);
+				trace!(target: "sub-libp2p",
+					"NAT traversal: remote observes us as {}; registering {} as one of our own addresses",
+					info.observed_addr,
+					ext_addr
+				);
 				listened_addrs.push(ext_addr.clone());
 				ext_addr.append(AddrComponent::P2P(shared.kad_system
 					.local_peer_id().clone().into_bytes()));
-				info!(target: "sub-libp2p", "New external node address: {}",
-					ext_addr);
+				info!(target: "sub-libp2p", "New external node address: {}", ext_addr);
 			}
 		}
 	}
@@ -1273,16 +1295,16 @@ fn ping_all<T, St, C>(
 		C: 'static {
 	let mut ping_futures = Vec::new();

-	for (peer, peer_id, pinger) in shared.network_state.cleanup_and_prepare_ping() {
+	for (peer, who, pinger) in shared.network_state.cleanup_and_prepare_ping() {
 		let shared = shared.clone();

-		let addr = Multiaddr::from(AddrComponent::P2P(peer_id.clone().into_bytes()));
+		let addr = Multiaddr::from(AddrComponent::P2P(who.clone().into_bytes()));
 		let fut = pinger
 			.get_or_dial(&swarm_controller, &addr, transport.clone())
 			.and_then(move |mut p| {
-				trace!(target: "sub-libp2p", "Pinging peer #{} aka. {:?}", peer, peer_id);
+				trace!(target: "sub-libp2p", "Pinging peer #{} aka. {:?}", peer, who);
 				p.ping()
-					.map(|()| peer_id)
+					.map(|()| who)
 					.map_err(|err| IoError::new(IoErrorKind::Other, err))
 			});
 		let ping_start_time = Instant::now();
@@ -1291,15 +1313,15 @@ fn ping_all<T, St, C>(
 				match val {
 					Err(err) => {
 						trace!(target: "sub-libp2p", "Error while pinging #{:?} => {:?}", peer, err);
-						shared.network_state.drop_peer(peer, None);	// None so that we don't print messages on such low-level issues.
+						shared.network_state.report_ping_failed(peer);
 						// Return Ok, otherwise we would close the ping service
 						Ok(())
 					},
-					Ok(peer_id) => {
+					Ok(who) => {
 						let elapsed = ping_start_time.elapsed();
 						trace!(target: "sub-libp2p", "Pong from #{:?} in {:?}", peer, elapsed);
 						shared.network_state.report_ping_duration(peer, elapsed);
-						shared.kad_system.update_kbuckets(peer_id);
+						shared.kad_system.update_kbuckets(who);
 						Ok(())
 					}
 				}
@@ -36,7 +36,8 @@ pub type ProtocolId = [u8; 3];
 pub type NodeId = H512;

 /// Local (temporary) peer session ID.
-pub type PeerId = usize;
+/// RENAME TO NodeIndex
+pub type NodeIndex = usize;

 /// Messages used to communitate with the event loop from other threads.
 #[derive(Clone)]
@@ -62,9 +63,9 @@ pub enum NetworkIoMessage {
 	/// Initliaze public interface.
 	InitPublicInterface,
 	/// Disconnect a peer.
-	Disconnect(PeerId),
+	Disconnect(NodeIndex),
 	/// Disconnect and temporary disable peer.
-	DisablePeer(PeerId),
+	DisablePeer(NodeIndex),
 	/// Network has been started with the host as the given enode.
 	NetworkStarted(String),
 }
@@ -240,16 +241,16 @@ impl<'a> fmt::Display for Severity<'a> {
 /// IO access point. This is passed to all IO handlers and provides an interface to the IO subsystem.
 pub trait NetworkContext {
 	/// Send a packet over the network to another peer.
-	fn send(&self, peer: PeerId, packet_id: PacketId, data: Vec<u8>);
+	fn send(&self, peer: NodeIndex, packet_id: PacketId, data: Vec<u8>);

 	/// Send a packet over the network to another peer using specified protocol.
-	fn send_protocol(&self, protocol: ProtocolId, peer: PeerId, packet_id: PacketId, data: Vec<u8>);
+	fn send_protocol(&self, protocol: ProtocolId, peer: NodeIndex, packet_id: PacketId, data: Vec<u8>);

 	/// Respond to a current network message. Panics if no there is no packet in the context. If the session is expired returns nothing.
 	fn respond(&self, packet_id: PacketId, data: Vec<u8>);

 	/// Report peer. Depending on the report, peer may be disconnected and possibly banned.
-	fn report_peer(&self, peer: PeerId, reason: Severity);
+	fn report_peer(&self, peer: NodeIndex, reason: Severity);

 	/// Check if the session is still active.
 	fn is_expired(&self) -> bool;
@@ -258,24 +259,24 @@ pub trait NetworkContext {
 	fn register_timer(&self, token: TimerToken, delay: Duration) -> Result<(), Error>;

 	/// Returns peer identification string
-	fn peer_client_version(&self, peer: PeerId) -> String;
+	fn peer_client_version(&self, peer: NodeIndex) -> String;

 	/// Returns information on p2p session
-	fn session_info(&self, peer: PeerId) -> Option<SessionInfo>;
+	fn session_info(&self, peer: NodeIndex) -> Option<SessionInfo>;

 	/// Returns max version for a given protocol.
-	fn protocol_version(&self, protocol: ProtocolId, peer: PeerId) -> Option<u8>;
+	fn protocol_version(&self, protocol: ProtocolId, peer: NodeIndex) -> Option<u8>;

 	/// Returns this object's subprotocol name.
 	fn subprotocol_name(&self) -> ProtocolId;
 }

 impl<'a, T> NetworkContext for &'a T where T: ?Sized + NetworkContext {
-	fn send(&self, peer: PeerId, packet_id: PacketId, data: Vec<u8>) {
+	fn send(&self, peer: NodeIndex, packet_id: PacketId, data: Vec<u8>) {
 		(**self).send(peer, packet_id, data)
 	}

-	fn send_protocol(&self, protocol: ProtocolId, peer: PeerId, packet_id: PacketId, data: Vec<u8>) {
+	fn send_protocol(&self, protocol: ProtocolId, peer: NodeIndex, packet_id: PacketId, data: Vec<u8>) {
 		(**self).send_protocol(protocol, peer, packet_id, data)
 	}

@@ -283,7 +284,7 @@ impl<'a, T> NetworkContext for &'a T where T: ?Sized + NetworkContext {
 		(**self).respond(packet_id, data)
 	}

-	fn report_peer(&self, peer: PeerId, reason: Severity) {
+	fn report_peer(&self, peer: NodeIndex, reason: Severity) {
 		(**self).report_peer(peer, reason)
 	}

@@ -295,15 +296,15 @@ impl<'a, T> NetworkContext for &'a T where T: ?Sized + NetworkContext {
 		(**self).register_timer(token, delay)
 	}

-	fn peer_client_version(&self, peer: PeerId) -> String {
+	fn peer_client_version(&self, peer: NodeIndex) -> String {
 		(**self).peer_client_version(peer)
 	}

-	fn session_info(&self, peer: PeerId) -> Option<SessionInfo> {
+	fn session_info(&self, peer: NodeIndex) -> Option<SessionInfo> {
 		(**self).session_info(peer)
 	}

-	fn protocol_version(&self, protocol: ProtocolId, peer: PeerId) -> Option<u8> {
+	fn protocol_version(&self, protocol: ProtocolId, peer: NodeIndex) -> Option<u8> {
 		(**self).protocol_version(protocol, peer)
 	}

@@ -319,11 +320,11 @@ pub trait NetworkProtocolHandler: Sync + Send {
 	/// Initialize the handler
 	fn initialize(&self, _io: &NetworkContext) {}
 	/// Called when new network packet received.
-	fn read(&self, io: &NetworkContext, peer: &PeerId, packet_id: u8, data: &[u8]);
+	fn read(&self, io: &NetworkContext, peer: &NodeIndex, packet_id: u8, data: &[u8]);
 	/// Called when new peer is connected. Only called when peer supports the same protocol.
-	fn connected(&self, io: &NetworkContext, peer: &PeerId);
+	fn connected(&self, io: &NetworkContext, peer: &NodeIndex);
 	/// Called when a previously connected peer disconnects.
-	fn disconnected(&self, io: &NetworkContext, peer: &PeerId);
+	fn disconnected(&self, io: &NetworkContext, peer: &NodeIndex);
 	/// Timer function called after a timeout created with `NetworkContext::timeout`.
 	fn timeout(&self, _io: &NetworkContext, _timer: TimerToken) {}
 }
@@ -66,12 +66,12 @@ impl NetworkProtocolHandler for TestProtocol {
 		io.register_timer(0, Duration::from_millis(10)).unwrap();
 	}

-	fn read(&self, _io: &NetworkContext, _peer: &PeerId, packet_id: u8, data: &[u8]) {
+	fn read(&self, _io: &NetworkContext, _peer: &NodeIndex, packet_id: u8, data: &[u8]) {
 		assert_eq!(packet_id, 33);
 		self.packet.lock().extend(data);
 	}

-	fn connected(&self, io: &NetworkContext, peer: &PeerId) {
+	fn connected(&self, io: &NetworkContext, peer: &NodeIndex) {
 		if self.drop_session {
 			io.report_peer(*peer, Severity::Bad("We are evil and just want to drop"))
 		} else {
@@ -79,7 +79,7 @@ impl NetworkProtocolHandler for TestProtocol {
 		}
 	}

-	fn disconnected(&self, _io: &NetworkContext, _peer: &PeerId) {
+	fn disconnected(&self, _io: &NetworkContext, _peer: &NodeIndex) {
 		self.got_disconnect.store(true, AtomicOrdering::Relaxed);
 	}

@@ -19,7 +19,7 @@ use std::cmp;
 use std::ops::Range;
 use std::collections::{HashMap, BTreeMap};
 use std::collections::hash_map::Entry;
-use network_libp2p::PeerId;
+use network_libp2p::NodeIndex;
 use runtime_primitives::traits::{Block as BlockT, NumberFor, As};
 use message;

@@ -29,7 +29,7 @@ const MAX_PARALLEL_DOWNLOADS: u32 = 1;
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub struct BlockData<B: BlockT> {
 	pub block: message::BlockData<B>,
-	pub origin: PeerId,
+	pub origin: NodeIndex,
 }

 #[derive(Debug)]
@@ -55,7 +55,7 @@ impl<B: BlockT> BlockRangeState<B> {
 pub struct BlockCollection<B: BlockT> {
 	/// Downloaded blocks.
 	blocks: BTreeMap<NumberFor<B>, BlockRangeState<B>>,
-	peer_requests: HashMap<PeerId, NumberFor<B>>,
+	peer_requests: HashMap<NodeIndex, NumberFor<B>>,
 }

 impl<B: BlockT> BlockCollection<B> {
@@ -74,7 +74,7 @@ impl<B: BlockT> BlockCollection<B> {
 	}

 	/// Insert a set of blocks into collection.
-	pub fn insert(&mut self, start: NumberFor<B>, blocks: Vec<message::BlockData<B>>, peer_id: PeerId) {
+	pub fn insert(&mut self, start: NumberFor<B>, blocks: Vec<message::BlockData<B>>, who: NodeIndex) {
 		if blocks.is_empty() {
 			return;
 		}
@@ -92,11 +92,11 @@ impl<B: BlockT> BlockCollection<B> {
 			_ => (),
 		}

-		self.blocks.insert(start, BlockRangeState::Complete(blocks.into_iter().map(|b| BlockData { origin: peer_id, block: b }).collect()));
+		self.blocks.insert(start, BlockRangeState::Complete(blocks.into_iter().map(|b| BlockData { origin: who, block: b }).collect()));
 	}

 	/// Returns a set of block hashes that require a header download. The returned set is marked as being downloaded.
-	pub fn needed_blocks(&mut self, peer_id: PeerId, count: usize, peer_best: NumberFor<B>, common: NumberFor<B>) -> Option<Range<NumberFor<B>>> {
+	pub fn needed_blocks(&mut self, who: NodeIndex, count: usize, peer_best: NumberFor<B>, common: NumberFor<B>) -> Option<Range<NumberFor<B>>> {
 		// First block number that we need to download
 		let first_different = common + As::sa(1);
 		let count = As::sa(count as u64);
@@ -125,11 +125,11 @@ impl<B: BlockT> BlockCollection<B> {
 		};
 		// crop to peers best
 		if range.start > peer_best {
-			trace!(target: "sync", "Out of range for peer {} ({} vs {})", peer_id, range.start, peer_best);
+			trace!(target: "sync", "Out of range for peer {} ({} vs {})", who, range.start, peer_best);
 			return None;
 		}
 		range.end = cmp::min(peer_best + As::sa(1), range.end);
-		self.peer_requests.insert(peer_id, range.start);
+		self.peer_requests.insert(who, range.start);
 		self.blocks.insert(range.start, BlockRangeState::Downloading{ len: range.end - range.start, downloading: downloading + 1 });
 		if range.end <= range.start {
 			panic!("Empty range {:?}, count={}, peer_best={}, common={}, blocks={:?}", range, count, peer_best, common, self.blocks);
@@ -162,8 +162,8 @@ impl<B: BlockT> BlockCollection<B> {
 		drained
 	}

-	pub fn clear_peer_download(&mut self, peer_id: PeerId) {
-		match self.peer_requests.entry(peer_id) {
+	pub fn clear_peer_download(&mut self, who: NodeIndex) {
+		match self.peer_requests.entry(who) {
 			Entry::Occupied(entry) => {
 				let start = entry.remove();
 				let remove = match self.blocks.get_mut(&start) {
@@ -20,7 +20,7 @@
 use std::collections::{HashMap, HashSet};
 use futures::sync::mpsc;
 use std::time::{Instant, Duration};
-use network_libp2p::PeerId;
+use network_libp2p::NodeIndex;
 use runtime_primitives::traits::{Block as BlockT, Header as HeaderT};
 use runtime_primitives::generic::BlockId;
 use message::{self, generic::Message as GenericMessage};
@@ -51,7 +51,7 @@ struct MessageEntry<B: BlockT> {

 /// Consensus network protocol handler. Manages statements and candidate requests.
 pub struct ConsensusGossip<B: BlockT> {
-	peers: HashMap<PeerId, PeerConsensus<B::Hash>>,
+	peers: HashMap<NodeIndex, PeerConsensus<B::Hash>>,
 	message_sink: Option<(mpsc::UnboundedSender<ConsensusMessage<B>>, B::Hash)>,
 	messages: Vec<MessageEntry<B>>,
 	message_hashes: HashSet<B::Hash>,
@@ -74,9 +74,9 @@ impl<B: BlockT> ConsensusGossip<B> where B::Header: HeaderT<Number=u64> {
 	}

 	/// Handle new connected peer.
-	pub fn new_peer(&mut self, protocol: &mut Context<B>, peer_id: PeerId, roles: Roles) {
+	pub fn new_peer(&mut self, protocol: &mut Context<B>, who: NodeIndex, roles: Roles) {
 		if roles.intersects(Roles::AUTHORITY | Roles::FULL) {
-			trace!(target:"gossip", "Registering {:?} {}", roles, peer_id);
+			trace!(target:"gossip", "Registering {:?} {}", roles, who);
 			// Send out all known messages.
 			// TODO: limit by size
 			let mut known_messages = HashSet::new();
@@ -87,9 +87,9 @@ impl<B: BlockT> ConsensusGossip<B> where B::Header: HeaderT<Number=u64> {
 					ConsensusMessage::ChainSpecific(ref msg, _) => GenericMessage::ChainSpecific(msg.clone()),
 				};

-				protocol.send_message(peer_id, message);
+				protocol.send_message(who, message);
 			}
-			self.peers.insert(peer_id, PeerConsensus {
+			self.peers.insert(who, PeerConsensus {
 				known_messages,
 			});
 		}
@@ -115,16 +115,16 @@ impl<B: BlockT> ConsensusGossip<B> where B::Header: HeaderT<Number=u64> {
 	}

 	/// Handles incoming BFT message, passing to stream and repropagating.
-	pub fn on_bft_message(&mut self, protocol: &mut Context<B>, peer_id: PeerId, message: message::LocalizedBftMessage<B>) {
-		if let Some((hash, message)) = self.handle_incoming(protocol, peer_id, ConsensusMessage::Bft(message)) {
+	pub fn on_bft_message(&mut self, protocol: &mut Context<B>, who: NodeIndex, message: message::LocalizedBftMessage<B>) {
+		if let Some((hash, message)) = self.handle_incoming(protocol, who, ConsensusMessage::Bft(message)) {
 			// propagate to other peers.
 			self.multicast(protocol, message, Some(hash));
 		}
 	}

 	/// Handles incoming chain-specific message and repropagates
-	pub fn on_chain_specific(&mut self, protocol: &mut Context<B>, peer_id: PeerId, message: Vec<u8>, parent_hash: B::Hash) {
-		if let Some((hash, message)) = self.handle_incoming(protocol, peer_id, ConsensusMessage::ChainSpecific(message, parent_hash)) {
+	pub fn on_chain_specific(&mut self, protocol: &mut Context<B>, who: NodeIndex, message: Vec<u8>, parent_hash: B::Hash) {
+		if let Some((hash, message)) = self.handle_incoming(protocol, who, ConsensusMessage::ChainSpecific(message, parent_hash)) {
 			// propagate to other peers.
 			self.multicast(protocol, message, Some(hash));
 		}
@@ -163,8 +163,8 @@ impl<B: BlockT> ConsensusGossip<B> where B::Header: HeaderT<Number=u64> {
 	}

 	/// Call when a peer has been disconnected to stop tracking gossip status.
-	pub fn peer_disconnected(&mut self, _protocol: &mut Context<B>, peer_id: PeerId) {
-		self.peers.remove(&peer_id);
+	pub fn peer_disconnected(&mut self, _protocol: &mut Context<B>, who: NodeIndex) {
+		self.peers.remove(&who);
 	}

 	/// Prune old or no longer relevant consensus messages.
@@ -195,7 +195,7 @@ impl<B: BlockT> ConsensusGossip<B> where B::Header: HeaderT<Number=u64> {
 		}
 	}

-	fn handle_incoming(&mut self, protocol: &mut Context<B>, peer_id: PeerId, message: ConsensusMessage<B>) -> Option<(B::Hash, ConsensusMessage<B>)> {
+	fn handle_incoming(&mut self, protocol: &mut Context<B>, who: NodeIndex, message: ConsensusMessage<B>) -> Option<(B::Hash, ConsensusMessage<B>)> {
 		let (hash, parent, message) = match message {
 			ConsensusMessage::Bft(msg) => {
 				let parent = msg.parent_hash;
@@ -223,7 +223,7 @@ impl<B: BlockT> ConsensusGossip<B> where B::Header: HeaderT<Number=u64> {
 		};

 		if self.message_hashes.contains(&hash) {
-			trace!(target:"gossip", "Ignored already known message from {}", peer_id);
+			trace!(target:"gossip", "Ignored already known message from {}", who);
 			return None;
 		}

@@ -234,14 +234,14 @@ impl<B: BlockT> ConsensusGossip<B> where B::Header: HeaderT<Number=u64> {
 			},
 			(Ok(info), Ok(Some(header))) => {
 				if header.number() < &info.chain.best_number {
-					trace!(target:"gossip", "Ignored ancient message from {}, hash={}", peer_id, parent);
+					trace!(target:"gossip", "Ignored ancient message from {}, hash={}", who, parent);
 					return None;
 				}
 			},
 			(Ok(_), Ok(None)) => {},
 		}

-		if let Some(ref mut peer) = self.peers.get_mut(&peer_id) {
+		if let Some(ref mut peer) = self.peers.get_mut(&who) {
 			peer.known_messages.insert(hash);
 			if let Some((sink, parent_hash)) = self.message_sink.take() {
 				if parent == parent_hash {
@@ -253,7 +253,7 @@ impl<B: BlockT> ConsensusGossip<B> where B::Header: HeaderT<Number=u64> {
 				self.message_sink = Some((sink, parent_hash));
 			}
 		} else {
-			trace!(target:"gossip", "Ignored statement from unregistered peer {}", peer_id);
+			trace!(target:"gossip", "Ignored statement from unregistered peer {}", who);
 			return None;
 		}

@@ -22,7 +22,7 @@ use std::sync::atomic::{AtomicBool, Ordering};
 use parking_lot::{Condvar, Mutex, RwLock};

 use client::{BlockOrigin, BlockStatus, ImportResult};
-use network_libp2p::{PeerId, Severity};
+use network_libp2p::{NodeIndex, Severity};
 use runtime_primitives::generic::BlockId;
 use runtime_primitives::traits::{Block as BlockT, Header as HeaderT, NumberFor, Zero};

@@ -202,9 +202,9 @@ trait SyncLinkApi<B: BlockT> {
 	/// Maintain sync.
 	fn maintain_sync(&mut self);
 	/// Disconnect from peer.
-	fn useless_peer(&mut self, peer_id: PeerId, reason: &str);
+	fn useless_peer(&mut self, who: NodeIndex, reason: &str);
 	/// Disconnect from peer and restart sync.
-	fn note_useless_and_restart_sync(&mut self, peer_id: PeerId, reason: &str);
+	fn note_useless_and_restart_sync(&mut self, who: NodeIndex, reason: &str);
 	/// Restart sync.
 	fn restart(&mut self);
 }
@@ -233,9 +233,9 @@ enum BlockImportResult<H: ::std::fmt::Debug + PartialEq, N: ::std::fmt::Debug +
 #[derive(Debug, PartialEq)]
 enum BlockImportError {
 	/// Disconnect from peer and continue import of next bunch of blocks.
-	Disconnect(PeerId),
+	Disconnect(NodeIndex),
 	/// Disconnect from peer and restart sync.
-	DisconnectAndRestart(PeerId),
+	DisconnectAndRestart(NodeIndex),
 	/// Restart sync.
 	Restart,
 }
@@ -356,16 +356,16 @@ fn process_import_result<'a, B: BlockT>(
 			link.block_imported(&hash, number);
 			1
 		},
-		Err(BlockImportError::Disconnect(peer_id)) => {
+		Err(BlockImportError::Disconnect(who)) => {
 			// TODO: FIXME: @arkpar BlockImport shouldn't be trying to manage the peer set.
 			// This should contain an actual reason.
-			link.useless_peer(peer_id, "Import result was stated Disconnect");
+			link.useless_peer(who, "Import result was stated Disconnect");
 			0
 		},
-		Err(BlockImportError::DisconnectAndRestart(peer_id)) => {
+		Err(BlockImportError::DisconnectAndRestart(who)) => {
 			// TODO: FIXME: @arkpar BlockImport shouldn't be trying to manage the peer set.
 			// This should contain an actual reason.
-			link.note_useless_and_restart_sync(peer_id, "Import result was stated DisconnectAndRestart");
+			link.note_useless_and_restart_sync(who, "Import result was stated DisconnectAndRestart");
 			0
 		},
 		Err(BlockImportError::Restart) => {
@@ -408,13 +408,13 @@ impl<'a, B: 'static + BlockT, E: ExecuteInContext<B>> SyncLinkApi<B> for SyncLin
 		self.with_sync(|sync, protocol| sync.maintain_sync(protocol))
 	}

-	fn useless_peer(&mut self, peer_id: PeerId, reason: &str) {
-		self.with_sync(|_, protocol| protocol.report_peer(peer_id, Severity::Useless(reason)))
+	fn useless_peer(&mut self, who: NodeIndex, reason: &str) {
+		self.with_sync(|_, protocol| protocol.report_peer(who, Severity::Useless(reason)))
 	}

-	fn note_useless_and_restart_sync(&mut self, peer_id: PeerId, reason: &str) {
+	fn note_useless_and_restart_sync(&mut self, who: NodeIndex, reason: &str) {
 		self.with_sync(|sync, protocol| {
-			protocol.report_peer(peer_id, Severity::Useless(reason));	// is this actually malign or just useless?
+			protocol.report_peer(who, Severity::Useless(reason));	// is this actually malign or just useless?
 			sync.restart(protocol);
 		})
 	}
@@ -490,8 +490,8 @@ pub mod tests {
 		fn chain(&self) -> &Client<Block> { &*self.chain }
 		fn block_imported(&mut self, _hash: &Hash, _number: NumberFor<Block>) { self.imported += 1; }
 		fn maintain_sync(&mut self) { self.maintains += 1; }
-		fn useless_peer(&mut self, _: PeerId, _: &str) { self.disconnects += 1; }
-		fn note_useless_and_restart_sync(&mut self, _: PeerId, _: &str) { self.disconnects += 1; self.restarts += 1; }
+		fn useless_peer(&mut self, _: NodeIndex, _: &str) { self.disconnects += 1; }
+		fn note_useless_and_restart_sync(&mut self, _: NodeIndex, _: &str) { self.disconnects += 1; self.restarts += 1; }
 		fn restart(&mut self) { self.restarts += 1; }
 	}

@@ -14,21 +14,21 @@
 // You should have received a copy of the GNU General Public License
 // along with Polkadot.  If not, see <http://www.gnu.org/licenses/>.?

-use network_libp2p::{NetworkContext, Severity, PeerId, SessionInfo};
+use network_libp2p::{NetworkContext, Severity, NodeIndex, SessionInfo};

 /// IO interface for the syncing handler.
 /// Provides peer connection management and an interface to the blockchain client.
 pub trait SyncIo {
 	/// Report a peer for misbehaviour.
-	fn report_peer(&mut self, peer_id: PeerId, reason: Severity);
+	fn report_peer(&mut self, who: NodeIndex, reason: Severity);
 	/// Send a packet to a peer.
-	fn send(&mut self, peer_id: PeerId, data: Vec<u8>);
+	fn send(&mut self, who: NodeIndex, data: Vec<u8>);
 	/// Returns peer identifier string
-	fn peer_info(&self, peer_id: PeerId) -> String {
-		peer_id.to_string()
+	fn peer_info(&self, who: NodeIndex) -> String {
+		who.to_string()
 	}
 	/// Returns information on p2p session
-	fn peer_session_info(&self, peer_id: PeerId) -> Option<SessionInfo>;
+	fn peer_session_info(&self, who: NodeIndex) -> Option<SessionInfo>;
 	/// Check if the session is expired
 	fn is_expired(&self) -> bool;
 }
@@ -48,24 +48,24 @@ impl<'s> NetSyncIo<'s> {
 }

 impl<'s> SyncIo for NetSyncIo<'s> {
-	fn report_peer(&mut self, peer_id: PeerId, reason: Severity) {
-		self.network.report_peer(peer_id, reason);
+	fn report_peer(&mut self, who: NodeIndex, reason: Severity) {
+		self.network.report_peer(who, reason);
 	}

-	fn send(&mut self, peer_id: PeerId, data: Vec<u8>) {
-		self.network.send(peer_id, 0, data)
+	fn send(&mut self, who: NodeIndex, data: Vec<u8>) {
+		self.network.send(who, 0, data)
 	}

-	fn peer_session_info(&self, peer_id: PeerId) -> Option<SessionInfo> {
-		self.network.session_info(peer_id)
+	fn peer_session_info(&self, who: NodeIndex) -> Option<SessionInfo> {
+		self.network.session_info(who)
 	}

 	fn is_expired(&self) -> bool {
 		self.network.is_expired()
 	}

-	fn peer_info(&self, peer_id: PeerId) -> String {
-		self.network.peer_client_version(peer_id)
+	fn peer_info(&self, who: NodeIndex) -> String {
+		self.network.peer_client_version(who)
 	}
 }

@@ -59,7 +59,7 @@ pub use service::{Service, FetchFuture, ConsensusService, BftMessageStream,
 	TransactionPool, Params, ManageNetwork, SyncProvider};
 pub use protocol::{ProtocolStatus, PeerInfo, Context};
 pub use sync::{Status as SyncStatus, SyncState};
-pub use network_libp2p::{NonReservedPeerMode, NetworkConfiguration, PeerId, ProtocolId, ConnectionFilter, ConnectionDirection, Severity};
+pub use network_libp2p::{NonReservedPeerMode, NetworkConfiguration, NodeIndex, ProtocolId, ConnectionFilter, ConnectionDirection, Severity};
 pub use message::{generic as generic_message, RequestId, BftMessage, LocalizedBftMessage, ConsensusVote, SignedConsensusVote, SignedConsensusMessage, SignedConsensusProposal, Status as StatusMessage};
 pub use error::Error;
 pub use config::{Roles, ProtocolConfig};
@@ -28,7 +28,7 @@ use client;
 use client::light::fetcher::{Fetcher, FetchChecker, RemoteCallRequest};
 use io::SyncIo;
 use message;
-use network_libp2p::{Severity, PeerId};
+use network_libp2p::{Severity, NodeIndex};
 use service;
 use runtime_primitives::traits::{Block as BlockT, Header as HeaderT};

@@ -38,16 +38,16 @@ const REQUEST_TIMEOUT: Duration = Duration::from_secs(15);
 /// On-demand service API.
 pub trait OnDemandService<Block: BlockT>: Send + Sync {
 	/// When new node is connected.
-	fn on_connect(&self, peer: PeerId, role: service::Roles);
+	fn on_connect(&self, peer: NodeIndex, role: service::Roles);

 	/// When node is disconnected.
-	fn on_disconnect(&self, peer: PeerId);
+	fn on_disconnect(&self, peer: NodeIndex);

 	/// Maintain peers requests.
 	fn maintain_peers(&self, io: &mut SyncIo);

 	/// When call response is received from remote node.
-	fn on_remote_call_response(&self, io: &mut SyncIo, peer: PeerId, response: message::RemoteCallResponse);
+	fn on_remote_call_response(&self, io: &mut SyncIo, peer: NodeIndex, response: message::RemoteCallResponse);
 }

 /// On-demand requests service. Dispatches requests to appropriate peers.
@@ -66,8 +66,8 @@ struct OnDemandCore<B: BlockT, E: service::ExecuteInContext<B>> {
 	service: Weak<E>,
 	next_request_id: u64,
 	pending_requests: VecDeque<Request<B>>,
-	active_peers: LinkedHashMap<PeerId, Request<B>>,
-	idle_peers: VecDeque<PeerId>,
+	active_peers: LinkedHashMap<NodeIndex, Request<B>>,
+	idle_peers: VecDeque<NodeIndex>,
 }

 struct Request<Block: BlockT> {
@@ -132,7 +132,7 @@ impl<B: BlockT, E> OnDemand<B, E> where
 	}

 	/// Try to accept response from given peer.
-	fn accept_response<F: FnOnce(Request<B>) -> Accept<B>>(&self, rtype: &str, io: &mut SyncIo, peer: PeerId, request_id: u64, try_accept: F) {
+	fn accept_response<F: FnOnce(Request<B>) -> Accept<B>>(&self, rtype: &str, io: &mut SyncIo, peer: NodeIndex, request_id: u64, try_accept: F) {
 		let mut core = self.core.lock();
 		let request = match core.remove(peer, request_id) {
 			Some(request) => request,
@@ -165,7 +165,7 @@ impl<B, E> OnDemandService<B> for OnDemand<B, E> where
 	E: service::ExecuteInContext<B>,
 	B::Header: HeaderT,
 {
-	fn on_connect(&self, peer: PeerId, role: service::Roles) {
+	fn on_connect(&self, peer: NodeIndex, role: service::Roles) {
 		if !role.intersects(service::Roles::FULL | service::Roles::AUTHORITY) { // TODO: correct?
 			return;
 		}
@@ -175,7 +175,7 @@ impl<B, E> OnDemandService<B> for OnDemand<B, E> where
 		core.dispatch();
 	}

-	fn on_disconnect(&self, peer: PeerId) {
+	fn on_disconnect(&self, peer: NodeIndex) {
 		let mut core = self.core.lock();
 		core.remove_peer(peer);
 		core.dispatch();
@@ -189,7 +189,7 @@ impl<B, E> OnDemandService<B> for OnDemand<B, E> where
 		core.dispatch();
 	}

-	fn on_remote_call_response(&self, io: &mut SyncIo, peer: PeerId, response: message::RemoteCallResponse) {
+	fn on_remote_call_response(&self, io: &mut SyncIo, peer: NodeIndex, response: message::RemoteCallResponse) {
 		self.accept_response("call", io, peer, response.id, |request| match request.data {
 			RequestData::RemoteCall(request, sender) => match self.checker.check_execution_proof(&request, response.proof) {
 				Ok(response) => {
@@ -222,11 +222,11 @@ impl<B, E> OnDemandCore<B, E> where
 	E: service::ExecuteInContext<B>,
 	B::Header: HeaderT,
 {
-	pub fn add_peer(&mut self, peer: PeerId) {
+	pub fn add_peer(&mut self, peer: NodeIndex) {
 		self.idle_peers.push_back(peer);
 	}

-	pub fn remove_peer(&mut self, peer: PeerId) {
+	pub fn remove_peer(&mut self, peer: NodeIndex) {
 		if let Some(request) = self.active_peers.remove(&peer) {
 			self.pending_requests.push_front(request);
 			return;
@@ -237,7 +237,7 @@ impl<B, E> OnDemandCore<B, E> where
 		}
 	}

-	pub fn maintain_peers(&mut self) -> Vec<PeerId> {
+	pub fn maintain_peers(&mut self) -> Vec<NodeIndex> {
 		let now = Instant::now();
 		let mut bad_peers = Vec::new();
 		loop {
@@ -263,7 +263,7 @@ impl<B, E> OnDemandCore<B, E> where
 		});
 	}

-	pub fn remove(&mut self, peer: PeerId, id: u64) -> Option<Request<B>> {
+	pub fn remove(&mut self, peer: NodeIndex, id: u64) -> Option<Request<B>> {
 		match self.active_peers.entry(peer) {
 			Entry::Occupied(entry) => match entry.get().id == id {
 				true => {
@@ -321,7 +321,7 @@ pub mod tests {
 	use client;
 	use client::light::fetcher::{Fetcher, FetchChecker, RemoteCallRequest};
 	use message;
-	use network_libp2p::PeerId;
+	use network_libp2p::NodeIndex;
 	use service::{Roles, ExecuteInContext};
 	use test::TestIo;
 	use super::{REQUEST_TIMEOUT, OnDemand, OnDemandService};
@@ -358,7 +358,7 @@ pub mod tests {
 		core.idle_peers.len() + core.active_peers.len()
 	}

-	fn receive_call_response(on_demand: &OnDemand<Block, DummyExecutor>, network: &mut TestIo, peer: PeerId, id: message::RequestId) {
+	fn receive_call_response(on_demand: &OnDemand<Block, DummyExecutor>, network: &mut TestIo, peer: NodeIndex, id: message::RequestId) {
 		on_demand.on_remote_call_response(network, peer, message::RemoteCallResponse {
 			id: id,
 			proof: vec![vec![2]],
@@ -21,7 +21,7 @@ use std::time;
 use parking_lot::RwLock;
 use runtime_primitives::traits::{Block as BlockT, Header as HeaderT, Hash, HashFor, As};
 use runtime_primitives::generic::BlockId;
-use network_libp2p::{PeerId, Severity};
+use network_libp2p::{NodeIndex, Severity};
 use codec::{Encode, Decode};

 use message::{self, Message};
@@ -55,7 +55,7 @@ pub struct Protocol<B: BlockT, S: Specialization<B>> {
 	specialization: RwLock<S>,
 	context_data: ContextData<B>,
 	// Connected peers pending Status message.
-	handshaking_peers: RwLock<HashMap<PeerId, time::Instant>>,
+	handshaking_peers: RwLock<HashMap<NodeIndex, time::Instant>>,
 	transaction_pool: Arc<TransactionPool<B>>,
 }
 /// Syncing status and statistics
@@ -110,13 +110,13 @@ pub trait Context<B: BlockT> {
 	fn client(&self) -> &::chain::Client<B>;

 	/// Point out that a peer has been malign or irresponsible or appeared lazy.
-	fn report_peer(&mut self, peer_id: PeerId, reason: Severity);
+	fn report_peer(&mut self, who: NodeIndex, reason: Severity);

 	/// Get peer info.
-	fn peer_info(&self, peer: PeerId) -> Option<PeerInfo<B>>;
+	fn peer_info(&self, peer: NodeIndex) -> Option<PeerInfo<B>>;

 	/// Send a message to a peer.
-	fn send_message(&mut self, peer_id: PeerId, data: ::message::Message<B>);
+	fn send_message(&mut self, who: NodeIndex, data: ::message::Message<B>);
 }

 /// Protocol context.
@@ -134,17 +134,17 @@ impl<'a, B: BlockT + 'a> ProtocolContext<'a, B> {
 	}

 	/// Send a message to a peer.
-	pub fn send_message(&mut self, peer_id: PeerId, message: Message<B>) {
-		send_message(&self.context_data.peers, self.io, peer_id, message)
+	pub fn send_message(&mut self, who: NodeIndex, message: Message<B>) {
+		send_message(&self.context_data.peers, self.io, who, message)
 	}

 	/// Point out that a peer has been malign or irresponsible or appeared lazy.
-	pub fn report_peer(&mut self, peer_id: PeerId, reason: Severity) {
-		self.io.report_peer(peer_id, reason);
+	pub fn report_peer(&mut self, who: NodeIndex, reason: Severity) {
+		self.io.report_peer(who, reason);
 	}

 	/// Get peer info.
-	pub fn peer_info(&self, peer: PeerId) -> Option<PeerInfo<B>> {
+	pub fn peer_info(&self, peer: NodeIndex) -> Option<PeerInfo<B>> {
 		self.context_data.peers.read().get(&peer).map(|p| {
 			PeerInfo {
 				roles: p.roles,
@@ -157,16 +157,16 @@ impl<'a, B: BlockT + 'a> ProtocolContext<'a, B> {
 }

 impl<'a, B: BlockT + 'a> Context<B> for ProtocolContext<'a, B> {
-	fn send_message(&mut self, peer_id: PeerId, message: Message<B>) {
-		ProtocolContext::send_message(self, peer_id, message);
+	fn send_message(&mut self, who: NodeIndex, message: Message<B>) {
+		ProtocolContext::send_message(self, who, message);
 	}

-	fn report_peer(&mut self, peer_id: PeerId, reason: Severity) {
-		ProtocolContext::report_peer(self, peer_id, reason);
+	fn report_peer(&mut self, who: NodeIndex, reason: Severity) {
+		ProtocolContext::report_peer(self, who, reason);
 	}

-	fn peer_info(&self, peer_id: PeerId) -> Option<PeerInfo<B>> {
-		ProtocolContext::peer_info(self, peer_id)
+	fn peer_info(&self, who: NodeIndex) -> Option<PeerInfo<B>> {
+		ProtocolContext::peer_info(self, who)
 	}

 	fn client(&self) -> &Client<B> {
@@ -177,7 +177,7 @@ impl<'a, B: BlockT + 'a> Context<B> for ProtocolContext<'a, B> {
 /// Data necessary to create a context.
 pub(crate) struct ContextData<B: BlockT> {
 	// All connected peers
-	peers: RwLock<HashMap<PeerId, Peer<B>>>,
+	peers: RwLock<HashMap<NodeIndex, Peer<B>>>,
 	chain: Arc<Client<B>>,
 }

@@ -228,63 +228,63 @@ impl<B: BlockT, S: Specialization<B>> Protocol<B, S> {
 		}
 	}

-	pub fn handle_packet(&self, io: &mut SyncIo, peer_id: PeerId, mut data: &[u8]) {
+	pub fn handle_packet(&self, io: &mut SyncIo, who: NodeIndex, mut data: &[u8]) {
 		let message: Message<B> = match Decode::decode(&mut data) {
 			Some(m) => m,
 			None => {
-				trace!(target: "sync", "Invalid packet from {}", peer_id);
-				io.report_peer(peer_id, Severity::Bad("Peer sent us a packet with invalid format"));
+				trace!(target: "sync", "Invalid packet from {}", who);
+				io.report_peer(who, Severity::Bad("Peer sent us a packet with invalid format"));
 				return;
 			}
 		};

 		match message {
-			GenericMessage::Status(s) => self.on_status_message(io, peer_id, s),
-			GenericMessage::BlockRequest(r) => self.on_block_request(io, peer_id, r),
+			GenericMessage::Status(s) => self.on_status_message(io, who, s),
+			GenericMessage::BlockRequest(r) => self.on_block_request(io, who, r),
 			GenericMessage::BlockResponse(r) => {
 				let request = {
 					let mut peers = self.context_data.peers.write();
-					if let Some(ref mut peer) = peers.get_mut(&peer_id) {
+					if let Some(ref mut peer) = peers.get_mut(&who) {
 						peer.request_timestamp = None;
 						match mem::replace(&mut peer.block_request, None) {
 							Some(r) => r,
 							None => {
-								io.report_peer(peer_id, Severity::Bad("Unexpected response packet received from peer"));
+								io.report_peer(who, Severity::Bad("Unexpected response packet received from peer"));
 								return;
 							}
 						}
 					} else {
-						io.report_peer(peer_id, Severity::Bad("Unexpected packet received from peer"));
+						io.report_peer(who, Severity::Bad("Unexpected packet received from peer"));
 						return;
 					}
 				};
 				if request.id != r.id {
-					trace!(target: "sync", "Ignoring mismatched response packet from {} (expected {} got {})", peer_id, request.id, r.id);
+					trace!(target: "sync", "Ignoring mismatched response packet from {} (expected {} got {})", who, request.id, r.id);
 					return;
 				}
-				self.on_block_response(io, peer_id, request, r);
+				self.on_block_response(io, who, request, r);
 			},
-			GenericMessage::BlockAnnounce(announce) => self.on_block_announce(io, peer_id, announce),
-			GenericMessage::Transactions(m) => self.on_extrinsics(io, peer_id, m),
-			GenericMessage::RemoteCallRequest(request) => self.on_remote_call_request(io, peer_id, request),
-			GenericMessage::RemoteCallResponse(response) => self.on_remote_call_response(io, peer_id, response),
-			other => self.specialization.write().on_message(&mut ProtocolContext::new(&self.context_data, io), peer_id, other),
+			GenericMessage::BlockAnnounce(announce) => self.on_block_announce(io, who, announce),
+			GenericMessage::Transactions(m) => self.on_extrinsics(io, who, m),
+			GenericMessage::RemoteCallRequest(request) => self.on_remote_call_request(io, who, request),
+			GenericMessage::RemoteCallResponse(response) => self.on_remote_call_response(io, who, response),
+			other => self.specialization.write().on_message(&mut ProtocolContext::new(&self.context_data, io), who, other),
 		}
 	}

-	pub fn send_message(&self, io: &mut SyncIo, peer_id: PeerId, message: Message<B>) {
-		send_message::<B>(&self.context_data.peers, io, peer_id, message)
+	pub fn send_message(&self, io: &mut SyncIo, who: NodeIndex, message: Message<B>) {
+		send_message::<B>(&self.context_data.peers, io, who, message)
 	}

 	/// Called when a new peer is connected
-	pub fn on_peer_connected(&self, io: &mut SyncIo, peer_id: PeerId) {
-		trace!(target: "sync", "Connected {}: {}", peer_id, io.peer_info(peer_id));
-		self.handshaking_peers.write().insert(peer_id, time::Instant::now());
-		self.send_status(io, peer_id);
+	pub fn on_peer_connected(&self, io: &mut SyncIo, who: NodeIndex) {
+		trace!(target: "sync", "Connected {}: {}", who, io.peer_info(who));
+		self.handshaking_peers.write().insert(who, time::Instant::now());
+		self.send_status(io, who);
 	}

 	/// Called by peer when it is disconnecting
-	pub fn on_peer_disconnected(&self, io: &mut SyncIo, peer: PeerId) {
+	pub fn on_peer_disconnected(&self, io: &mut SyncIo, peer: NodeIndex) {
 		trace!(target: "sync", "Disconnecting {}: {}", peer, io.peer_info(peer));

 		// lock all the the peer lists so that add/remove peer events are in order
@@ -305,7 +305,7 @@ impl<B: BlockT, S: Specialization<B>> Protocol<B, S> {
 		}
 	}

-	fn on_block_request(&self, io: &mut SyncIo, peer: PeerId, request: message::BlockRequest<B>) {
+	fn on_block_request(&self, io: &mut SyncIo, peer: NodeIndex, request: message::BlockRequest<B>) {
 		trace!(target: "sync", "BlockRequest {} from {}: from {:?} to {:?} max {:?}", request.id, peer, request.from, request.to, request.max);
 		let mut blocks = Vec::new();
 		let mut id = match request.from {
@@ -351,7 +351,7 @@ impl<B: BlockT, S: Specialization<B>> Protocol<B, S> {
 		self.send_message(io, peer, GenericMessage::BlockResponse(response))
 	}

-	fn on_block_response(&self, io: &mut SyncIo, peer: PeerId, request: message::BlockRequest<B>, response: message::BlockResponse<B>) {
+	fn on_block_response(&self, io: &mut SyncIo, peer: NodeIndex, request: message::BlockRequest<B>, response: message::BlockResponse<B>) {
 		// TODO: validate response
 		trace!(target: "sync", "BlockResponse {} from {} with {} blocks", response.id, peer, response.blocks.len());
 		self.sync.write().on_block_data(&mut ProtocolContext::new(&self.context_data, io), peer, request, response);
@@ -369,12 +369,12 @@ impl<B: BlockT, S: Specialization<B>> Protocol<B, S> {
 		{
 			let peers = self.context_data.peers.read();
 			let handshaking_peers = self.handshaking_peers.read();
-			for (peer_id, timestamp) in peers.iter()
+			for (who, timestamp) in peers.iter()
 				.filter_map(|(id, peer)| peer.request_timestamp.as_ref().map(|r| (id, r)))
 				.chain(handshaking_peers.iter()) {
 				if (tick - *timestamp).as_secs() > REQUEST_TIMEOUT_SEC {
-					trace!(target: "sync", "Timeout {}", peer_id);
-					aborting.push(*peer_id);
+					trace!(target: "sync", "Timeout {}", who);
+					aborting.push(*who);
 				}
 			}
 		}
@@ -385,7 +385,7 @@ impl<B: BlockT, S: Specialization<B>> Protocol<B, S> {
 		}
 	}

-	pub fn peer_info(&self, peer: PeerId) -> Option<PeerInfo<B>> {
+	pub fn peer_info(&self, peer: NodeIndex) -> Option<PeerInfo<B>> {
 		self.context_data.peers.read().get(&peer).map(|p| {
 			PeerInfo {
 				roles: p.roles,
@@ -397,26 +397,26 @@ impl<B: BlockT, S: Specialization<B>> Protocol<B, S> {
 	}

 	/// Called by peer to report status
-	fn on_status_message(&self, io: &mut SyncIo, peer_id: PeerId, status: message::Status<B>) {
-		trace!(target: "sync", "New peer {} {:?}", peer_id, status);
+	fn on_status_message(&self, io: &mut SyncIo, who: NodeIndex, status: message::Status<B>) {
+		trace!(target: "sync", "New peer {} {:?}", who, status);
 		if io.is_expired() {
-			trace!(target: "sync", "Status packet from expired session {}:{}", peer_id, io.peer_info(peer_id));
+			trace!(target: "sync", "Status packet from expired session {}:{}", who, io.peer_info(who));
 			return;
 		}

 		{
 			let mut peers = self.context_data.peers.write();
 			let mut handshaking_peers = self.handshaking_peers.write();
-			if peers.contains_key(&peer_id) {
-				debug!(target: "sync", "Unexpected status packet from {}:{}", peer_id, io.peer_info(peer_id));
+			if peers.contains_key(&who) {
+				debug!(target: "sync", "Unexpected status packet from {}:{}", who, io.peer_info(who));
 				return;
 			}
 			if status.genesis_hash != self.genesis_hash {
-				io.report_peer(peer_id, Severity::Bad(&format!("Peer is on different chain (our genesis: {} theirs: {})", self.genesis_hash, status.genesis_hash)));
+				io.report_peer(who, Severity::Bad(&format!("Peer is on different chain (our genesis: {} theirs: {})", self.genesis_hash, status.genesis_hash)));
 				return;
 			}
 			if status.version != CURRENT_VERSION {
-				io.report_peer(peer_id, Severity::Bad(&format!("Peer using unsupported protocol version {}", status.version)));
+				io.report_peer(who, Severity::Bad(&format!("Peer using unsupported protocol version {}", status.version)));
 				return;
 			}

@@ -431,27 +431,27 @@ impl<B: BlockT, S: Specialization<B>> Protocol<B, S> {
 				known_blocks: HashSet::new(),
 				next_request_id: 0,
 			};
-			peers.insert(peer_id.clone(), peer);
-			handshaking_peers.remove(&peer_id);
-			debug!(target: "sync", "Connected {} {}", peer_id, io.peer_info(peer_id));
+			peers.insert(who.clone(), peer);
+			handshaking_peers.remove(&who);
+			debug!(target: "sync", "Connected {} {}", who, io.peer_info(who));
 		}

 		let mut context = ProtocolContext::new(&self.context_data, io);
-		self.sync.write().new_peer(&mut context, peer_id);
-		self.specialization.write().on_connect(&mut context, peer_id, status.clone());
-		self.on_demand.as_ref().map(|s| s.on_connect(peer_id, status.roles));
+		self.sync.write().new_peer(&mut context, who);
+		self.specialization.write().on_connect(&mut context, who, status.clone());
+		self.on_demand.as_ref().map(|s| s.on_connect(who, status.roles));
 	}

 	/// Called when peer sends us new extrinsics
-	fn on_extrinsics(&self, _io: &mut SyncIo, peer_id: PeerId, extrinsics: message::Transactions<B::Extrinsic>) {
+	fn on_extrinsics(&self, _io: &mut SyncIo, who: NodeIndex, extrinsics: message::Transactions<B::Extrinsic>) {
 		// Accept extrinsics only when fully synced
 		if self.sync.read().status().state != SyncState::Idle {
-			trace!(target: "sync", "{} Ignoring extrinsics while syncing", peer_id);
+			trace!(target: "sync", "{} Ignoring extrinsics while syncing", who);
 			return;
 		}
-		trace!(target: "sync", "Received {} extrinsics from {}", extrinsics.len(), peer_id);
+		trace!(target: "sync", "Received {} extrinsics from {}", extrinsics.len(), who);
 		let mut peers = self.context_data.peers.write();
-		if let Some(ref mut peer) = peers.get_mut(&peer_id) {
+		if let Some(ref mut peer) = peers.get_mut(&who) {
 			for t in extrinsics {
 				if let Some(hash) = self.transaction_pool.import(&t) {
 					peer.known_extrinsics.insert(hash);
@@ -473,7 +473,7 @@ impl<B: BlockT, S: Specialization<B>> Protocol<B, S> {

 		let mut propagated_to = HashMap::new();
 		let mut peers = self.context_data.peers.write();
-		for (peer_id, ref mut peer) in peers.iter_mut() {
+		for (who, ref mut peer) in peers.iter_mut() {
 			let (hashes, to_send): (Vec<_>, Vec<_>) = extrinsics
 				.iter()
 				.cloned()
@@ -481,7 +481,7 @@ impl<B: BlockT, S: Specialization<B>> Protocol<B, S> {
 				.unzip();

 			if !to_send.is_empty() {
-				let node_id = io.peer_session_info(*peer_id).map(|info| match info.id {
+				let node_id = io.peer_session_info(*who).map(|info| match info.id {
 					Some(id) => format!("{}@{:x}", info.remote_address, id),
 					None => info.remote_address.clone(),
 				});
@@ -491,15 +491,15 @@ impl<B: BlockT, S: Specialization<B>> Protocol<B, S> {
 						propagated_to.entry(hash).or_insert_with(Vec::new).push(id.clone());
 					}
 				}
-				trace!(target: "sync", "Sending {} transactions to {}", to_send.len(), peer_id);
-				self.send_message(io, *peer_id, GenericMessage::Transactions(to_send));
+				trace!(target: "sync", "Sending {} transactions to {}", to_send.len(), who);
+				self.send_message(io, *who, GenericMessage::Transactions(to_send));
 			}
 		}
 		self.transaction_pool.on_broadcasted(propagated_to);
 	}

 	/// Send Status message
-	fn send_status(&self, io: &mut SyncIo, peer_id: PeerId) {
+	fn send_status(&self, io: &mut SyncIo, who: NodeIndex) {
 		if let Ok(info) = self.context_data.chain.info() {
 			let status = message::generic::Status {
 				version: CURRENT_VERSION,
@@ -509,7 +509,7 @@ impl<B: BlockT, S: Specialization<B>> Protocol<B, S> {
 				best_hash: info.chain.best_hash,
 				chain_status: self.specialization.read().status(),
 			};
-			self.send_message(io, peer_id, GenericMessage::Status(status))
+			self.send_message(io, who, GenericMessage::Status(status))
 		}
 	}

@@ -533,16 +533,16 @@ impl<B: BlockT, S: Specialization<B>> Protocol<B, S> {
 		self.abort();
 	}

-	pub fn on_block_announce(&self, io: &mut SyncIo, peer_id: PeerId, announce: message::BlockAnnounce<B::Header>) {
+	pub fn on_block_announce(&self, io: &mut SyncIo, who: NodeIndex, announce: message::BlockAnnounce<B::Header>) {
 		let header = announce.header;
 		let hash = header.hash();
 		{
 			let mut peers = self.context_data.peers.write();
-			if let Some(ref mut peer) = peers.get_mut(&peer_id) {
+			if let Some(ref mut peer) = peers.get_mut(&who) {
 				peer.known_blocks.insert(hash.clone());
 			}
 		}
-		self.sync.write().on_block_announce(&mut ProtocolContext::new(&self.context_data, io), peer_id, hash, &header);
+		self.sync.write().on_block_announce(&mut ProtocolContext::new(&self.context_data, io), who, hash, &header);
 	}

 	pub fn on_block_imported(&self, io: &mut SyncIo, hash: B::Hash, header: &B::Header) {
@@ -561,35 +561,35 @@ impl<B: BlockT, S: Specialization<B>> Protocol<B, S> {
 		// send out block announcements
 		let mut peers = self.context_data.peers.write();

-		for (peer_id, ref mut peer) in peers.iter_mut() {
+		for (who, ref mut peer) in peers.iter_mut() {
 			if peer.known_blocks.insert(hash.clone()) {
-				trace!(target: "sync", "Announcing block {:?} to {}", hash, peer_id);
-				self.send_message(io, *peer_id, GenericMessage::BlockAnnounce(message::BlockAnnounce {
+				trace!(target: "sync", "Announcing block {:?} to {}", hash, who);
+				self.send_message(io, *who, GenericMessage::BlockAnnounce(message::BlockAnnounce {
 					header: header.clone()
 				}));
 			}
 		}
 	}

-	fn on_remote_call_request(&self, io: &mut SyncIo, peer_id: PeerId, request: message::RemoteCallRequest<B::Hash>) {
-		trace!(target: "sync", "Remote call request {} from {} ({} at {})", request.id, peer_id, request.method, request.block);
+	fn on_remote_call_request(&self, io: &mut SyncIo, who: NodeIndex, request: message::RemoteCallRequest<B::Hash>) {
+		trace!(target: "sync", "Remote call request {} from {} ({} at {})", request.id, who, request.method, request.block);
 		let proof = match self.context_data.chain.execution_proof(&request.block, &request.method, &request.data) {
 			Ok((_, proof)) => proof,
 			Err(error) => {
 				trace!(target: "sync", "Remote call request {} from {} ({} at {}) failed with: {}",
-					request.id, peer_id, request.method, request.block, error);
+					request.id, who, request.method, request.block, error);
 				Default::default()
 			},
 		};

-		self.send_message(io, peer_id, GenericMessage::RemoteCallResponse(message::RemoteCallResponse {
+		self.send_message(io, who, GenericMessage::RemoteCallResponse(message::RemoteCallResponse {
 			id: request.id, proof,
 		}));
 	}

-	fn on_remote_call_response(&self, io: &mut SyncIo, peer_id: PeerId, response: message::RemoteCallResponse) {
-		trace!(target: "sync", "Remote call response {} from {}", response.id, peer_id);
-		self.on_demand.as_ref().map(|s| s.on_remote_call_response(io, peer_id, response));
+	fn on_remote_call_response(&self, io: &mut SyncIo, who: NodeIndex, response: message::RemoteCallResponse) {
+		trace!(target: "sync", "Remote call response {} from {}", response.id, who);
+		self.on_demand.as_ref().map(|s| s.on_remote_call_response(io, who, response));
 	}

 	/// Execute a closure with access to a network context and specialization.
@@ -600,11 +600,11 @@ impl<B: BlockT, S: Specialization<B>> Protocol<B, S> {
 	}
 }

-fn send_message<B: BlockT>(peers: &RwLock<HashMap<PeerId, Peer<B>>>, io: &mut SyncIo, peer_id: PeerId, mut message: Message<B>) {
+fn send_message<B: BlockT>(peers: &RwLock<HashMap<NodeIndex, Peer<B>>>, io: &mut SyncIo, who: NodeIndex, mut message: Message<B>) {
 	match &mut message {
 		&mut GenericMessage::BlockRequest(ref mut r) => {
 			let mut peers = peers.write();
-			if let Some(ref mut peer) = peers.get_mut(&peer_id) {
+			if let Some(ref mut peer) = peers.get_mut(&who) {
 				r.id = peer.next_request_id;
 				peer.next_request_id = peer.next_request_id + 1;
 				peer.block_request = Some(r.clone());
@@ -613,7 +613,7 @@ fn send_message<B: BlockT>(peers: &RwLock<HashMap<PeerId, Peer<B>>>, io: &mut Sy
 		},
 		_ => (),
 	}
-	io.send(peer_id, message.encode());
+	io.send(who, message.encode());
 }

 /// Hash a message.
@@ -19,7 +19,7 @@ use std::sync::Arc;
 use std::io;
 use std::time::Duration;
 use futures::sync::{oneshot, mpsc};
-use network_libp2p::{NetworkProtocolHandler, NetworkContext, PeerId, ProtocolId,
+use network_libp2p::{NetworkProtocolHandler, NetworkContext, NodeIndex, ProtocolId,
 NetworkConfiguration , NonReservedPeerMode, ErrorKind};
 use network_libp2p::{NetworkService};
 use core_io::{TimerToken};
@@ -244,8 +244,8 @@ impl<B: BlockT + 'static, S: Specialization<B>> SyncProvider<B> for Service<B, S
 		self.network.with_context_eval(self.protocol_id, |ctx| {
 			let peer_ids = self.network.connected_peers();

-			peer_ids.into_iter().filter_map(|peer_id| {
-				let session_info = match ctx.session_info(peer_id) {
+			peer_ids.into_iter().filter_map(|who| {
+				let session_info = match ctx.session_info(who) {
 					None => return None,
 					Some(info) => info,
 				};
@@ -256,7 +256,7 @@ impl<B: BlockT + 'static, S: Specialization<B>> SyncProvider<B> for Service<B, S
 					capabilities: session_info.peer_capabilities.into_iter().map(|c| c.to_string()).collect(),
 					remote_address: session_info.remote_address,
 					local_address: session_info.local_address,
-					dot_info: self.handler.protocol.peer_info(peer_id),
+					dot_info: self.handler.protocol.peer_info(who),
 				})
 			}).collect()
 		}).unwrap_or_else(Vec::new)
@@ -276,15 +276,15 @@ impl<B: BlockT + 'static, S: Specialization<B>> NetworkProtocolHandler for Proto
 			.expect("Error registering transaction propagation timer");
 	}

-	fn read(&self, io: &NetworkContext, peer: &PeerId, _packet_id: u8, data: &[u8]) {
+	fn read(&self, io: &NetworkContext, peer: &NodeIndex, _packet_id: u8, data: &[u8]) {
 		self.protocol.handle_packet(&mut NetSyncIo::new(io), *peer, data);
 	}

-	fn connected(&self, io: &NetworkContext, peer: &PeerId) {
+	fn connected(&self, io: &NetworkContext, peer: &NodeIndex) {
 		self.protocol.on_peer_connected(&mut NetSyncIo::new(io), *peer);
 	}

-	fn disconnected(&self, io: &NetworkContext, peer: &PeerId) {
+	fn disconnected(&self, io: &NetworkContext, peer: &NodeIndex) {
 		self.protocol.on_peer_disconnected(&mut NetSyncIo::new(io), *peer);
 	}

@@ -16,7 +16,7 @@

 //! Specializations of the substrate network protocol to allow more complex forms of communication.

-use ::PeerId;
+use ::NodeIndex;
 use runtime_primitives::traits::Block as BlockT;
 use protocol::Context;

@@ -29,13 +29,13 @@ pub trait Specialization<B: BlockT>: Send + Sync + 'static {
 	fn on_start(&mut self) { }

 	/// Called when a peer successfully handshakes.
-	fn on_connect(&mut self, ctx: &mut Context<B>, peer_id: PeerId, status: ::message::Status<B>);
+	fn on_connect(&mut self, ctx: &mut Context<B>, who: NodeIndex, status: ::message::Status<B>);

 	/// Called when a peer is disconnected. If the peer ID is unknown, it should be ignored.
-	fn on_disconnect(&mut self, ctx: &mut Context<B>, peer_id: PeerId);
+	fn on_disconnect(&mut self, ctx: &mut Context<B>, who: NodeIndex);

 	/// Called when a network-specific message arrives.
-	fn on_message(&mut self, ctx: &mut Context<B>, peer_id: PeerId, message: ::message::Message<B>);
+	fn on_message(&mut self, ctx: &mut Context<B>, who: NodeIndex, message: ::message::Message<B>);

 	/// Called on abort.
 	fn on_abort(&mut self) { }
@@ -17,7 +17,7 @@
 use std::collections::HashMap;
 use std::sync::Arc;
 use protocol::Context;
-use network_libp2p::{Severity, PeerId};
+use network_libp2p::{Severity, NodeIndex};
 use client::{BlockStatus, BlockOrigin, ClientInfo};
 use client::error::Error as ClientError;
 use blocks::{self, BlockCollection};
@@ -51,7 +51,7 @@ enum PeerSyncState<B: BlockT> {
 /// Relay chain sync strategy.
 pub struct ChainSync<B: BlockT> {
 	genesis_hash: B::Hash,
-	peers: HashMap<PeerId, PeerSync<B>>,
+	peers: HashMap<NodeIndex, PeerSync<B>>,
 	blocks: BlockCollection<B>,
 	best_queued_number: NumberFor<B>,
 	best_queued_hash: B::Hash,
@@ -119,47 +119,47 @@ impl<B: BlockT> ChainSync<B> {
 	}

 	/// Handle new connected peer.
-	pub(crate) fn new_peer(&mut self, protocol: &mut Context<B>, peer_id: PeerId) {
-		if let Some(info) = protocol.peer_info(peer_id) {
+	pub(crate) fn new_peer(&mut self, protocol: &mut Context<B>, who: NodeIndex) {
+		if let Some(info) = protocol.peer_info(who) {
 			match (block_status(&*protocol.client(), &*self.import_queue, info.best_hash), info.best_number) {
 				(Err(e), _) => {
 					debug!(target:"sync", "Error reading blockchain: {:?}", e);
-					protocol.report_peer(peer_id, Severity::Useless(&format!("Error legimimately reading blockchain status: {:?}", e)));
+					protocol.report_peer(who, Severity::Useless(&format!("Error legimimately reading blockchain status: {:?}", e)));
 				},
 				(Ok(BlockStatus::KnownBad), _) => {
-					protocol.report_peer(peer_id, Severity::Bad(&format!("New peer with known bad best block {} ({}).", info.best_hash, info.best_number)));
+					protocol.report_peer(who, Severity::Bad(&format!("New peer with known bad best block {} ({}).", info.best_hash, info.best_number)));
 				},
 				(Ok(BlockStatus::Unknown), b) if b == As::sa(0) => {
-					protocol.report_peer(peer_id, Severity::Bad(&format!("New peer with unknown genesis hash {} ({}).", info.best_hash, info.best_number)));
+					protocol.report_peer(who, Severity::Bad(&format!("New peer with unknown genesis hash {} ({}).", info.best_hash, info.best_number)));
 				},
 				(Ok(BlockStatus::Unknown), _) => {
 					let our_best = self.best_queued_number;
 					if our_best > As::sa(0) {
 						debug!(target:"sync", "New peer with unknown best hash {} ({}), searching for common ancestor.", info.best_hash, info.best_number);
-						self.peers.insert(peer_id, PeerSync {
+						self.peers.insert(who, PeerSync {
 							common_hash: self.genesis_hash,
 							common_number: As::sa(0),
 							best_hash: info.best_hash,
 							best_number: info.best_number,
 							state: PeerSyncState::AncestorSearch(our_best),
 						});
-						Self::request_ancestry(protocol, peer_id, our_best)
+						Self::request_ancestry(protocol, who, our_best)
 					} else {
 						// We are at genesis, just start downloading
 						debug!(target:"sync", "New peer with best hash {} ({}).", info.best_hash, info.best_number);
-						self.peers.insert(peer_id, PeerSync {
+						self.peers.insert(who, PeerSync {
 							common_hash: self.genesis_hash,
 							common_number: As::sa(0),
 							best_hash: info.best_hash,
 							best_number: info.best_number,
 							state: PeerSyncState::Available,
 						});
-						self.download_new(protocol, peer_id)
+						self.download_new(protocol, who)
 					}
 				},
 				(Ok(BlockStatus::Queued), _) | (Ok(BlockStatus::InChain), _) => {
 					debug!(target:"sync", "New peer with known best hash {} ({}).", info.best_hash, info.best_number);
-					self.peers.insert(peer_id, PeerSync {
+					self.peers.insert(who, PeerSync {
 						common_hash: info.best_hash,
 						common_number: info.best_number,
 						best_hash: info.best_hash,
@@ -171,27 +171,27 @@ impl<B: BlockT> ChainSync<B> {
 		}
 	}

-	pub(crate) fn on_block_data(&mut self, protocol: &mut Context<B>, peer_id: PeerId, _request: message::BlockRequest<B>, response: message::BlockResponse<B>) {
-		let new_blocks = if let Some(ref mut peer) = self.peers.get_mut(&peer_id) {
+	pub(crate) fn on_block_data(&mut self, protocol: &mut Context<B>, who: NodeIndex, _request: message::BlockRequest<B>, response: message::BlockResponse<B>) {
+		let new_blocks = if let Some(ref mut peer) = self.peers.get_mut(&who) {
 			match peer.state {
 				PeerSyncState::DownloadingNew(start_block) => {
-					self.blocks.clear_peer_download(peer_id);
+					self.blocks.clear_peer_download(who);
 					peer.state = PeerSyncState::Available;

-					self.blocks.insert(start_block, response.blocks, peer_id);
+					self.blocks.insert(start_block, response.blocks, who);
 					self.blocks.drain(self.best_queued_number + As::sa(1))
 				},
 				PeerSyncState::DownloadingStale(_) => {
 					peer.state = PeerSyncState::Available;
 					response.blocks.into_iter().map(|b| blocks::BlockData {
-						origin: peer_id,
+						origin: who,
 						block: b
 					}).collect()
 				},
 				PeerSyncState::AncestorSearch(n) => {
 					match response.blocks.get(0) {
 						Some(ref block) => {
-							trace!(target: "sync", "Got ancestry block #{} ({}) from peer {}", n, block.hash, peer_id);
+							trace!(target: "sync", "Got ancestry block #{} ({}) from peer {}", n, block.hash, who);
 							match protocol.client().block_hash(n) {
 								Ok(Some(block_hash)) if block_hash == block.hash => {
 									if peer.common_number < n {
@@ -199,30 +199,30 @@ impl<B: BlockT> ChainSync<B> {
 										peer.common_number = n;
 									}
 									peer.state = PeerSyncState::Available;
-									trace!(target:"sync", "Found common ancestor for peer {}: {} ({})", peer_id, block.hash, n);
+									trace!(target:"sync", "Found common ancestor for peer {}: {} ({})", who, block.hash, n);
 									vec![]
 								},
 								Ok(our_best) if n > As::sa(0) => {
-									trace!(target:"sync", "Ancestry block mismatch for peer {}: theirs: {} ({}), ours: {:?}", peer_id, block.hash, n, our_best);
+									trace!(target:"sync", "Ancestry block mismatch for peer {}: theirs: {} ({}), ours: {:?}", who, block.hash, n, our_best);
 									let n = n - As::sa(1);
 									peer.state = PeerSyncState::AncestorSearch(n);
-									Self::request_ancestry(protocol, peer_id, n);
+									Self::request_ancestry(protocol, who, n);
 									return;
 								},
 								Ok(_) => { // genesis mismatch
-									trace!(target:"sync", "Ancestry search: genesis mismatch for peer {}", peer_id);
-									protocol.report_peer(peer_id, Severity::Bad("Ancestry search: genesis mismatch for peer"));
+									trace!(target:"sync", "Ancestry search: genesis mismatch for peer {}", who);
+									protocol.report_peer(who, Severity::Bad("Ancestry search: genesis mismatch for peer"));
 									return;
 								},
 								Err(e) => {
-									protocol.report_peer(peer_id, Severity::Useless(&format!("Error answering legitimate blockchain query: {:?}", e)));
+									protocol.report_peer(who, Severity::Useless(&format!("Error answering legitimate blockchain query: {:?}", e)));
 									return;
 								}
 							}
 						},
 						None => {
-							trace!(target:"sync", "Invalid response when searching for ancestor from {}", peer_id);
-							protocol.report_peer(peer_id, Severity::Bad("Invalid response when searching for ancestor"));
+							trace!(target:"sync", "Invalid response when searching for ancestor from {}", who);
+							protocol.report_peer(who, Severity::Bad("Invalid response when searching for ancestor"));
 							return;
 						}
 					}
@@ -241,7 +241,7 @@ impl<B: BlockT> ChainSync<B> {
 	}

 	pub fn maintain_sync(&mut self, protocol: &mut Context<B>) {
-		let peers: Vec<PeerId> = self.peers.keys().map(|p| *p).collect();
+		let peers: Vec<NodeIndex> = self.peers.keys().map(|p| *p).collect();
 		for peer in peers {
 			self.download_new(protocol, peer);
 		}
@@ -267,9 +267,9 @@ impl<B: BlockT> ChainSync<B> {
 		self.block_imported(&hash, best_header.number().clone())
 	}

-	pub(crate) fn on_block_announce(&mut self, protocol: &mut Context<B>, peer_id: PeerId, hash: B::Hash, header: &B::Header) {
+	pub(crate) fn on_block_announce(&mut self, protocol: &mut Context<B>, who: NodeIndex, hash: B::Hash, header: &B::Header) {
 		let number = *header.number();
-		if let Some(ref mut peer) = self.peers.get_mut(&peer_id) {
+		if let Some(ref mut peer) = self.peers.get_mut(&who) {
 			if number > peer.best_number {
 				peer.best_number = number;
 				peer.best_hash = hash;
@@ -285,17 +285,17 @@ impl<B: BlockT> ChainSync<B> {
 			let stale = number <= self.best_queued_number;
 			if stale {
 				if !self.is_known_or_already_downloading(protocol, header.parent_hash()) {
-					trace!(target: "sync", "Ignoring unknown stale block announce from {}: {} {:?}", peer_id, hash, header);
+					trace!(target: "sync", "Ignoring unknown stale block announce from {}: {} {:?}", who, hash, header);
 				} else {
-					trace!(target: "sync", "Downloading new stale block announced from {}: {} {:?}", peer_id, hash, header);
-					self.download_stale(protocol, peer_id, &hash);
+					trace!(target: "sync", "Downloading new stale block announced from {}: {} {:?}", who, hash, header);
+					self.download_stale(protocol, who, &hash);
 				}
 			} else {
-				trace!(target: "sync", "Downloading new block announced from {}: {} {:?}", peer_id, hash, header);
-				self.download_new(protocol, peer_id);
+				trace!(target: "sync", "Downloading new block announced from {}: {} {:?}", who, hash, header);
+				self.download_new(protocol, who);
 			}
 		} else {
-			trace!(target: "sync", "Known block announce from {}: {}", peer_id, hash);
+			trace!(target: "sync", "Known block announce from {}: {}", who, hash);
 		}
 	}

@@ -304,16 +304,16 @@ impl<B: BlockT> ChainSync<B> {
 			|| block_status(&*protocol.client(), &*self.import_queue, *hash).ok().map_or(false, |s| s != BlockStatus::Unknown)
 	}

-	pub(crate) fn peer_disconnected(&mut self, protocol: &mut Context<B>, peer_id: PeerId) {
-		self.blocks.clear_peer_download(peer_id);
-		self.peers.remove(&peer_id);
+	pub(crate) fn peer_disconnected(&mut self, protocol: &mut Context<B>, who: NodeIndex) {
+		self.blocks.clear_peer_download(who);
+		self.peers.remove(&who);
 		self.maintain_sync(protocol);
 	}

 	pub(crate) fn restart(&mut self, protocol: &mut Context<B>) {
 		self.import_queue.clear();
 		self.blocks.clear();
-		let ids: Vec<PeerId> = self.peers.keys().map(|p| *p).collect();
+		let ids: Vec<NodeIndex> = self.peers.keys().map(|p| *p).collect();
 		for id in ids {
 			self.new_peer(protocol, id);
 		}
@@ -336,8 +336,8 @@ impl<B: BlockT> ChainSync<B> {
 	}

 	// Download old block.
-	fn download_stale(&mut self, protocol: &mut Context<B>, peer_id: PeerId, hash: &B::Hash) {
-		if let Some(ref mut peer) = self.peers.get_mut(&peer_id) {
+	fn download_stale(&mut self, protocol: &mut Context<B>, who: NodeIndex, hash: &B::Hash) {
+		if let Some(ref mut peer) = self.peers.get_mut(&who) {
 			match peer.state {
 				PeerSyncState::Available => {
 					let request = message::generic::BlockRequest {
@@ -349,7 +349,7 @@ impl<B: BlockT> ChainSync<B> {
 						max: Some(1),
 					};
 					peer.state = PeerSyncState::DownloadingStale(*hash);
-					protocol.send_message(peer_id, GenericMessage::BlockRequest(request));
+					protocol.send_message(who, GenericMessage::BlockRequest(request));
 				},
 				_ => (),
 			}
@@ -357,8 +357,8 @@ impl<B: BlockT> ChainSync<B> {
 	}

 	// Issue a request for a peer to download new blocks, if any are available
-	fn download_new(&mut self, protocol: &mut Context<B>, peer_id: PeerId) {
-		if let Some(ref mut peer) = self.peers.get_mut(&peer_id) {
+	fn download_new(&mut self, protocol: &mut Context<B>, who: NodeIndex) {
+		if let Some(ref mut peer) = self.peers.get_mut(&who) {
 			let import_status = self.import_queue.status();
 			// when there are too many blocks in the queue => do not try to download new blocks
 			if import_status.importing_count > MAX_IMPORING_BLOCKS {
@@ -367,11 +367,11 @@ impl<B: BlockT> ChainSync<B> {
 			// we should not download already queued blocks
 			let common_number = ::std::cmp::max(peer.common_number, import_status.best_importing_number);

-			trace!(target: "sync", "Considering new block download from {}, common block is {}, best is {:?}", peer_id, common_number, peer.best_number);
+			trace!(target: "sync", "Considering new block download from {}, common block is {}, best is {:?}", who, common_number, peer.best_number);
 			match peer.state {
 				PeerSyncState::Available => {
-					if let Some(range) = self.blocks.needed_blocks(peer_id, MAX_BLOCKS_TO_REQUEST, peer.best_number, common_number) {
-						trace!(target: "sync", "Requesting blocks from {}, ({} to {})", peer_id, range.start, range.end);
+					if let Some(range) = self.blocks.needed_blocks(who, MAX_BLOCKS_TO_REQUEST, peer.best_number, common_number) {
+						trace!(target: "sync", "Requesting blocks from {}, ({} to {})", who, range.start, range.end);
 						let request = message::generic::BlockRequest {
 							id: 0,
 							fields: self.required_block_attributes.clone(),
@@ -381,7 +381,7 @@ impl<B: BlockT> ChainSync<B> {
 							max: Some((range.end - range.start).as_() as u32),
 						};
 						peer.state = PeerSyncState::DownloadingNew(range.start);
-						protocol.send_message(peer_id, GenericMessage::BlockRequest(request));
+						protocol.send_message(who, GenericMessage::BlockRequest(request));
 					} else {
 						trace!(target: "sync", "Nothing to request");
 					}
@@ -391,8 +391,8 @@ impl<B: BlockT> ChainSync<B> {
 		}
 	}

-	fn request_ancestry(protocol: &mut Context<B>, peer_id: PeerId, block: NumberFor<B>) {
-		trace!(target: "sync", "Requesting ancestry block #{} from {}", block, peer_id);
+	fn request_ancestry(protocol: &mut Context<B>, who: NodeIndex, block: NumberFor<B>) {
+		trace!(target: "sync", "Requesting ancestry block #{} from {}", block, who);
 		let request = message::generic::BlockRequest {
 			id: 0,
 			fields: message::BlockAttributes::HEADER | message::BlockAttributes::JUSTIFICATION,
@@ -401,7 +401,7 @@ impl<B: BlockT> ChainSync<B> {
 			direction: message::Direction::Ascending,
 			max: Some(1),
 		};
-		protocol.send_message(peer_id, GenericMessage::BlockRequest(request));
+		protocol.send_message(who, GenericMessage::BlockRequest(request));
 	}
 }

@@ -28,7 +28,7 @@ use io::SyncIo;
 use protocol::{Context, Protocol};
 use config::ProtocolConfig;
 use service::TransactionPool;
-use network_libp2p::{PeerId, SessionInfo, Severity};
+use network_libp2p::{NodeIndex, SessionInfo, Severity};
 use keyring::Keyring;
 use codec::Encode;
 use import_queue::tests::SyncImportQueue;
@@ -41,29 +41,29 @@ pub struct DummySpecialization;
 impl Specialization<Block> for DummySpecialization {
 	fn status(&self) -> Vec<u8> { vec![] }

-	fn on_connect(&mut self, _ctx: &mut Context<Block>, _peer_id: PeerId, _status: ::message::Status<Block>) {
+	fn on_connect(&mut self, _ctx: &mut Context<Block>, _peer_id: NodeIndex, _status: ::message::Status<Block>) {

 	}

-	fn on_disconnect(&mut self, _ctx: &mut Context<Block>, _peer_id: PeerId) {
+	fn on_disconnect(&mut self, _ctx: &mut Context<Block>, _peer_id: NodeIndex) {

 	}

-	fn on_message(&mut self, _ctx: &mut Context<Block>, _peer_id: PeerId, _message: ::message::Message<Block>) {
+	fn on_message(&mut self, _ctx: &mut Context<Block>, _peer_id: NodeIndex, _message: ::message::Message<Block>) {

 	}
 }

 pub struct TestIo<'p> {
 	queue: &'p RwLock<VecDeque<TestPacket>>,
-	pub to_disconnect: HashSet<PeerId>,
+	pub to_disconnect: HashSet<NodeIndex>,
 	packets: Vec<TestPacket>,
-	peers_info: HashMap<PeerId, String>,
-	_sender: Option<PeerId>,
+	peers_info: HashMap<NodeIndex, String>,
+	_sender: Option<NodeIndex>,
 }

 impl<'p> TestIo<'p> where {
-	pub fn new(queue: &'p RwLock<VecDeque<TestPacket>>, sender: Option<PeerId>) -> TestIo<'p> {
+	pub fn new(queue: &'p RwLock<VecDeque<TestPacket>>, sender: Option<NodeIndex>) -> TestIo<'p> {
 		TestIo {
 			queue: queue,
 			_sender: sender,
@@ -81,28 +81,28 @@ impl<'p> Drop for TestIo<'p> {
 }

 impl<'p> SyncIo for TestIo<'p> {
-	fn report_peer(&mut self, peer_id: PeerId, _reason: Severity) {
-		self.to_disconnect.insert(peer_id);
+	fn report_peer(&mut self, who: NodeIndex, _reason: Severity) {
+		self.to_disconnect.insert(who);
 	}

 	fn is_expired(&self) -> bool {
 		false
 	}

-	fn send(&mut self, peer_id: PeerId, data: Vec<u8>) {
+	fn send(&mut self, who: NodeIndex, data: Vec<u8>) {
 		self.packets.push(TestPacket {
 			data: data,
-			recipient: peer_id,
+			recipient: who,
 		});
 	}

-	fn peer_info(&self, peer_id: PeerId) -> String {
-		self.peers_info.get(&peer_id)
+	fn peer_info(&self, who: NodeIndex) -> String {
+		self.peers_info.get(&who)
 			.cloned()
-			.unwrap_or_else(|| peer_id.to_string())
+			.unwrap_or_else(|| who.to_string())
 	}

-	fn peer_session_info(&self, _peer_id: PeerId) -> Option<SessionInfo> {
+	fn peer_session_info(&self, _peer_id: NodeIndex) -> Option<SessionInfo> {
 		None
 	}
 }
@@ -110,7 +110,7 @@ impl<'p> SyncIo for TestIo<'p> {
 /// Mocked subprotocol packet
 pub struct TestPacket {
 	data: Vec<u8>,
-	recipient: PeerId,
+	recipient: NodeIndex,
 }

 pub struct Peer {
@@ -129,18 +129,18 @@ impl Peer {
 	}

 	/// Called on connection to other indicated peer.
-	fn on_connect(&self, other: PeerId) {
+	fn on_connect(&self, other: NodeIndex) {
 		self.sync.on_peer_connected(&mut TestIo::new(&self.queue, Some(other)), other);
 	}

 	/// Called on disconnect from other indicated peer.
-	fn on_disconnect(&self, other: PeerId) {
+	fn on_disconnect(&self, other: NodeIndex) {
 		let mut io = TestIo::new(&self.queue, Some(other));
 		self.sync.on_peer_disconnected(&mut io, other);
 	}

 	/// Receive a message from another peer. Return a set of peers to disconnect.
-	fn receive_message(&self, from: PeerId, msg: TestPacket) -> HashSet<PeerId> {
+	fn receive_message(&self, from: NodeIndex, msg: TestPacket) -> HashSet<NodeIndex> {
 		let mut io = TestIo::new(&self.queue, Some(from));
 		self.sync.handle_packet(&mut io, from, &msg.data);
 		self.flush();
@@ -219,7 +219,7 @@ impl TransactionPool<Block> for EmptyTransactionPool {
 pub struct TestNet {
 	peers: Vec<Arc<Peer>>,
 	started: bool,
-	disconnect_events: Vec<(PeerId, PeerId)>, //disconnected (initiated by, to)
+	disconnect_events: Vec<(NodeIndex, NodeIndex)>, //disconnected (initiated by, to)
 }

 impl TestNet {
@@ -264,7 +264,7 @@ impl TestNet {
 			self.peers[peer].start();
 			for client in 0..self.peers.len() {
 				if peer != client {
-					self.peers[peer].on_connect(client as PeerId);
+					self.peers[peer].on_connect(client as NodeIndex);
 				}
 			}
 		}
@@ -278,17 +278,17 @@ impl TestNet {
 				let disconnecting = {
 					let recipient = packet.recipient;
 					trace!("--- {} -> {} ---", peer, recipient);
-					let to_disconnect = self.peers[recipient].receive_message(peer as PeerId, packet);
+					let to_disconnect = self.peers[recipient].receive_message(peer as NodeIndex, packet);
 					for d in &to_disconnect {
 						// notify this that disconnecting peers are disconnecting
-						self.peers[recipient].on_disconnect(*d as PeerId);
+						self.peers[recipient].on_disconnect(*d as NodeIndex);
 						self.disconnect_events.push((peer, *d));
 					}
 					to_disconnect
 				};
 				for d in &disconnecting {
 					// notify other peers that this peer is disconnecting
-					self.peers[*d].on_disconnect(peer as PeerId);
+					self.peers[*d].on_disconnect(peer as NodeIndex);
 				}
 			}