diff --git a/substrate/core/network-libp2p/src/behaviour.rs b/substrate/core/network-libp2p/src/behaviour.rs
index c6401ef79e..a10f3697d8 100644
--- a/substrate/core/network-libp2p/src/behaviour.rs
+++ b/substrate/core/network-libp2p/src/behaviour.rs
@@ -26,9 +26,9 @@ use libp2p::kad::{Kademlia, KademliaOut};
 use libp2p::mdns::{Mdns, MdnsEvent};
 use libp2p::ping::{Ping, PingEvent};
 use log::{debug, trace, warn};
-use std::{cmp, io, fmt, time::Duration, time::Instant};
+use std::{cmp, io, fmt, time::Duration};
 use tokio_io::{AsyncRead, AsyncWrite};
-use tokio_timer::Delay;
+use tokio_timer::{Delay, clock::Clock};
 use void;
 
 /// General behaviour of the network.
@@ -73,14 +73,16 @@ impl<TMessage, TSubstream> Behaviour<TMessage, TSubstream> {
 			kademlia.add_connected_address(peer_id, addr.clone());
 		}
 
+		let clock = Clock::new();
 		Behaviour {
 			ping: Ping::new(),
 			custom_protocols,
 			discovery: DiscoveryBehaviour {
 				user_defined: known_addresses,
 				kademlia,
-				next_kad_random_query: Delay::new(Instant::now()),
+				next_kad_random_query: Delay::new(clock.now()),
 				duration_to_next_kad: Duration::from_secs(1),
+				clock,
 			},
 			identify,
 			mdns: if enable_mdns {
@@ -331,6 +333,8 @@ pub struct DiscoveryBehaviour<TSubstream> {
 	next_kad_random_query: Delay,
 	/// After `next_kad_random_query` triggers, the next one triggers after this duration.
 	duration_to_next_kad: Duration,
+	/// `Clock` instance that uses the current execution context's source of time.
+	clock: Clock,
 }
 
 impl<TSubstream> NetworkBehaviour for DiscoveryBehaviour<TSubstream>
@@ -408,7 +412,7 @@ where
 					self.kademlia.find_node(random_peer_id);
 
 					// Reset the `Delay` to the next random.
-					self.next_kad_random_query.reset(Instant::now() + self.duration_to_next_kad);
+					self.next_kad_random_query.reset(self.clock.now() + self.duration_to_next_kad);
 					self.duration_to_next_kad = cmp::min(self.duration_to_next_kad * 2,
 						Duration::from_secs(60));
 				},
diff --git a/substrate/core/network-libp2p/src/custom_proto/behaviour.rs b/substrate/core/network-libp2p/src/custom_proto/behaviour.rs
index 7f29711a51..ca1363fab1 100644
--- a/substrate/core/network-libp2p/src/custom_proto/behaviour.rs
+++ b/substrate/core/network-libp2p/src/custom_proto/behaviour.rs
@@ -24,6 +24,7 @@ use log::{debug, error, trace, warn};
 use smallvec::SmallVec;
 use std::{collections::hash_map::Entry, cmp, error, io, marker::PhantomData, mem, time::Duration, time::Instant};
 use tokio_io::{AsyncRead, AsyncWrite};
+use tokio_timer::clock::Clock;
 
 /// Network behaviour that handles opening substreams for custom protocols with other nodes.
 ///
@@ -78,6 +79,9 @@ pub struct CustomProto<TMessage, TSubstream> {
 
 	/// Marker to pin the generics.
 	marker: PhantomData<TSubstream>,
+
+	/// `Clock` instance that uses the current execution context's source of time.
+	clock: Clock,
 }
 
 /// State of a peer we're connected to.
@@ -214,6 +218,7 @@ impl<TMessage, TSubstream> CustomProto<TMessage, TSubstream> {
 			next_incoming_index: substrate_peerset::IncomingIndex(0),
 			events: SmallVec::new(),
 			marker: PhantomData,
+			clock: Clock::new(),
 		}
 	}
 
@@ -244,7 +249,7 @@ impl<TMessage, TSubstream> CustomProto<TMessage, TSubstream> {
 				debug!(target: "sub-libp2p", "PSM <= Dropped({:?})", peer_id);
 				self.peerset.dropped(peer_id.clone());
 				let banned_until = Some(if let Some(ban) = ban {
-					cmp::max(timer.deadline(), Instant::now() + ban)
+					cmp::max(timer.deadline(), self.clock.now() + ban)
 				} else {
 					timer.deadline()
 				});
@@ -260,7 +265,8 @@ impl<TMessage, TSubstream> CustomProto<TMessage, TSubstream> {
 					peer_id: peer_id.clone(),
 					event: CustomProtoHandlerIn::Disable,
 				});
-				let banned_until = ban.map(|dur| Instant::now() + dur);
+				let clock = &self.clock;
+				let banned_until = ban.map(|dur| clock.now() + dur);
 				*entry.into_mut() = PeerState::Disabled { open, connected_point, banned_until }
 			},
 
@@ -281,7 +287,8 @@ impl<TMessage, TSubstream> CustomProto<TMessage, TSubstream> {
 					peer_id: peer_id.clone(),
 					event: CustomProtoHandlerIn::Disable,
 				});
-				let banned_until = ban.map(|dur| Instant::now() + dur);
+				let clock = &self.clock;
+				let banned_until = ban.map(|dur| clock.now() + dur);
 				*entry.into_mut() = PeerState::Disabled { open: false, connected_point, banned_until }
 			},
 
@@ -369,7 +376,7 @@ impl<TMessage, TSubstream> CustomProto<TMessage, TSubstream> {
 		};
 
 		match mem::replace(occ_entry.get_mut(), PeerState::Poisoned) {
-			PeerState::Banned { ref until } if *until > Instant::now() => {
+			PeerState::Banned { ref until } if *until > self.clock.now() => {
 				debug!(target: "sub-libp2p", "PSM => Connect({:?}): Will start to connect at \
 					until {:?}", occ_entry.key(), until);
 				*occ_entry.into_mut() = PeerState::PendingRequest {
@@ -385,7 +392,7 @@ impl<TMessage, TSubstream> CustomProto<TMessage, TSubstream> {
 			},
 
 			PeerState::Disabled { open, ref connected_point, banned_until: Some(ref banned) }
-				if *banned > Instant::now() => {
+				if *banned > self.clock.now() => {
 				debug!(target: "sub-libp2p", "PSM => Connect({:?}): Has idle connection through \
 					{:?} but node is banned until {:?}", occ_entry.key(), connected_point, banned);
 				*occ_entry.into_mut() = PeerState::DisabledPendingEnable {
@@ -758,7 +765,7 @@ where
 				PeerState::Requested | PeerState::PendingRequest { .. } => {
 					debug!(target: "sub-libp2p", "Libp2p => Dial failure for {:?}", peer_id);
 					*entry.into_mut() = PeerState::Banned {
-						until: Instant::now() + Duration::from_secs(5)
+						until: self.clock.now() + Duration::from_secs(5)
 					};
 					debug!(target: "sub-libp2p", "PSM <= Dropped({:?})", peer_id);
 					self.peerset.dropped(peer_id.clone())
diff --git a/substrate/core/network-libp2p/src/custom_proto/handler.rs b/substrate/core/network-libp2p/src/custom_proto/handler.rs
index 969df7799b..b3c577ce4c 100644
--- a/substrate/core/network-libp2p/src/custom_proto/handler.rs
+++ b/substrate/core/network-libp2p/src/custom_proto/handler.rs
@@ -28,7 +28,7 @@ use log::{debug, error, warn};
 use smallvec::{smallvec, SmallVec};
 use std::{error, fmt, io, marker::PhantomData, mem, time::Duration, time::Instant};
 use tokio_io::{AsyncRead, AsyncWrite};
-use tokio_timer::Delay;
+use tokio_timer::{Delay, clock::Clock};
 use void::Void;
 
 /// Implements the `IntoProtocolsHandler` trait of libp2p.
@@ -119,15 +119,17 @@ where
 	type Handler = CustomProtoHandler<TMessage, TSubstream>;
 
 	fn into_handler(self, remote_peer_id: &PeerId) -> Self::Handler {
+		let clock = Clock::new();
 		CustomProtoHandler {
 			protocol: self.protocol,
 			remote_peer_id: remote_peer_id.clone(),
 			state: ProtocolState::Init {
 				substreams: SmallVec::new(),
-				init_deadline: Delay::new(Instant::now() + Duration::from_secs(5))
+				init_deadline: Delay::new(clock.now() + Duration::from_secs(5))
 			},
 			events_queue: SmallVec::new(),
-			warm_up_end: Instant::now() + Duration::from_secs(5),
+			warm_up_end: clock.now() + Duration::from_secs(5),
+			clock,
 		}
 	}
 }
@@ -153,6 +155,10 @@ pub struct CustomProtoHandler<TMessage, TSubstream> {
 	/// We have a warm-up period after creating the handler during which we don't shut down the
 	/// connection.
 	warm_up_end: Instant,
+
+	/// `Clock` instance that uses the current execution context's source of time.
+	clock: Clock,
+
 }
 
 /// State of the handler.
@@ -404,7 +410,7 @@ where
 						});
 					}
 					ProtocolState::Opening {
-						deadline: Delay::new(Instant::now() + Duration::from_secs(60))
+						deadline: Delay::new(self.clock.now() + Duration::from_secs(60))
 					}
 
 				} else if incoming.iter().any(|s| s.is_multiplex()) {
@@ -514,7 +520,7 @@ where
 			ProtocolState::Init { substreams, mut init_deadline } => {
 				match init_deadline.poll() {
 					Ok(Async::Ready(())) => {
-						init_deadline.reset(Instant::now() + Duration::from_secs(60));
+						init_deadline.reset(self.clock.now() + Duration::from_secs(60));
 						error!(target: "sub-libp2p", "Handler initialization process is too long \
 							with {:?}", self.remote_peer_id)
 					},
@@ -529,7 +535,7 @@ where
 			ProtocolState::Opening { mut deadline } => {
 				match deadline.poll() {
 					Ok(Async::Ready(())) => {
-						deadline.reset(Instant::now() + Duration::from_secs(60));
+						deadline.reset(self.clock.now() + Duration::from_secs(60));
 						let event = CustomProtoHandlerOut::ProtocolError {
 							is_severe: true,
 							error: "Timeout when opening protocol".to_string().into(),
@@ -543,7 +549,7 @@ where
 					},
 					Err(_) => {
 						error!(target: "sub-libp2p", "Tokio timer has errored");
-						deadline.reset(Instant::now() + Duration::from_secs(60));
+						deadline.reset(self.clock.now() + Duration::from_secs(60));
 						return_value = None;
 						ProtocolState::Opening { deadline }
 					},
@@ -613,7 +619,7 @@ where
 						info: (),
 					});
 					ProtocolState::Opening {
-						deadline: Delay::new(Instant::now() + Duration::from_secs(60))
+						deadline: Delay::new(self.clock.now() + Duration::from_secs(60))
 					}
 				} else {
 					return_value = None;
@@ -829,7 +835,7 @@ where TSubstream: AsyncRead + AsyncWrite, TMessage: CustomMessage {
 	}
 
 	fn connection_keep_alive(&self) -> KeepAlive {
-		if self.warm_up_end >= Instant::now() {
+		if self.warm_up_end >= self.clock.now() {
 			return KeepAlive::Until(self.warm_up_end)
 		}