diff --git a/substrate/client/authority-discovery/src/lib.rs b/substrate/client/authority-discovery/src/lib.rs
index e5b7c986a4..bc76c14331 100644
--- a/substrate/client/authority-discovery/src/lib.rs
+++ b/substrate/client/authority-discovery/src/lib.rs
@@ -58,7 +58,7 @@ use futures::task::{Context, Poll};
 use futures::{Future, FutureExt, ready, Stream, StreamExt};
 use futures_timer::Delay;
 
-use codec::{Decode, Encode};
+use codec::Decode;
 use error::{Error, Result};
 use log::{debug, error, log_enabled};
 use prometheus_endpoint::{Counter, CounterVec, Gauge, Opts, U64, register};
@@ -262,16 +262,16 @@ where
 			)
 			.map_err(|_| Error::Signing)?;
 
-		for (sign_result, key) in signatures.iter().zip(keys) {
+		for (sign_result, key) in signatures.into_iter().zip(keys) {
 			let mut signed_addresses = vec![];
 
 			// sign_with_all returns Result<Signature, Error> signature
 			// is generated for a public key that is supported.
 			// Verify that all signatures exist for all provided keys.
-			let signature = sign_result.as_ref().map_err(|_| Error::MissingSignature(key.clone()))?;
+			let signature = sign_result.map_err(|_| Error::MissingSignature(key.clone()))?;
 			schema::SignedAuthorityAddresses {
 				addresses: serialized_addresses.clone(),
-				signature: Encode::encode(&signature),
+				signature,
 			}
 			.encode(&mut signed_addresses)
 				.map_err(Error::EncodingProto)?;
diff --git a/substrate/client/authority-discovery/src/tests.rs b/substrate/client/authority-discovery/src/tests.rs
index c9b5e392d8..c13bca894c 100644
--- a/substrate/client/authority-discovery/src/tests.rs
+++ b/substrate/client/authority-discovery/src/tests.rs
@@ -162,8 +162,8 @@ sp_api::mock_impl_runtime_apis! {
 	}
 }
 
-#[derive(Default)]
 struct TestNetwork {
+	peer_id: PeerId,
 	// Whenever functions on `TestNetwork` are called, the function arguments are added to the
 	// vectors below.
 	pub put_value_call: Arc<Mutex<Vec<(kad::record::Key, Vec<u8>)>>>,
@@ -171,6 +171,17 @@ struct TestNetwork {
 	pub set_priority_group_call: Arc<Mutex<Vec<(String, HashSet<Multiaddr>)>>>,
 }
 
+impl Default for TestNetwork {
+	fn default() -> Self {
+		TestNetwork {
+			peer_id: PeerId::random(),
+			put_value_call: Default::default(),
+			get_value_call: Default::default(),
+			set_priority_group_call: Default::default(),
+		}
+	}
+}
+
 impl NetworkProvider for TestNetwork {
 	fn set_priority_group(
 		&self,
@@ -193,11 +204,11 @@ impl NetworkProvider for TestNetwork {
 
 impl NetworkStateInfo for TestNetwork {
 	fn local_peer_id(&self) -> PeerId {
-		PeerId::random()
+		self.peer_id.clone()
 	}
 
 	fn external_addresses(&self) -> Vec<Multiaddr> {
-		vec![]
+		vec!["/ip6/2001:db8::".parse().unwrap()]
 	}
 }
 
@@ -224,34 +235,6 @@ fn new_registers_metrics() {
 	assert!(registry.gather().len() > 0);
 }
 
-#[test]
-fn publish_ext_addresses_puts_record_on_dht() {
-	let (_dht_event_tx, dht_event_rx) = channel(1000);
-	let network: Arc<TestNetwork> = Arc::new(Default::default());
-	let key_store = KeyStore::new();
-	let public = key_store
-		.write()
-		.sr25519_generate_new(key_types::AUTHORITY_DISCOVERY, None)
-		.unwrap();
-	let test_api = Arc::new(TestApi {
-		authorities: vec![public.into()],
-	});
-
-	let mut authority_discovery = AuthorityDiscovery::new(
-		test_api,
-		network.clone(),
-		vec![],
-		dht_event_rx.boxed(),
-		Role::Authority(key_store),
-		None,
-	);
-
-	authority_discovery.publish_ext_addresses().unwrap();
-
-	// Expect authority discovery to put a new record onto the dht.
-	assert_eq!(network.put_value_call.lock().unwrap().len(), 1);
-}
-
 #[test]
 fn request_addresses_of_others_triggers_dht_get_query() {
 	let _ = ::env_logger::try_init();
@@ -284,15 +267,57 @@ fn request_addresses_of_others_triggers_dht_get_query() {
 }
 
 #[test]
-fn handle_dht_events_with_value_found_should_call_set_priority_group() {
+fn publish_discover_cycle() {
 	let _ = ::env_logger::try_init();
 
-	// Create authority discovery.
+	// Node A publishing its address.
+
+	let (_dht_event_tx, dht_event_rx) = channel(1000);
+
+	let network: Arc<TestNetwork> = Arc::new(Default::default());
+	let node_a_multiaddr = {
+		let peer_id = network.local_peer_id();
+		let address = network.external_addresses().pop().unwrap();
+
+		address.with(libp2p::core::multiaddr::Protocol::P2p(
+			peer_id.into(),
+		))
+	};
+
+	let key_store = KeyStore::new();
+	let node_a_public = key_store
+		.write()
+		.sr25519_generate_new(key_types::AUTHORITY_DISCOVERY, None)
+		.unwrap();
+	let test_api = Arc::new(TestApi {
+		authorities: vec![node_a_public.into()],
+	});
+
+	let mut authority_discovery = AuthorityDiscovery::new(
+		test_api,
+		network.clone(),
+		vec![],
+		dht_event_rx.boxed(),
+		Role::Authority(key_store),
+		None,
+	);
+
+	authority_discovery.publish_ext_addresses().unwrap();
+
+	// Expect authority discovery to put a new record onto the dht.
+	assert_eq!(network.put_value_call.lock().unwrap().len(), 1);
+
+	let dht_event = {
+		let (key, value) = network.put_value_call.lock().unwrap().pop().unwrap();
+		sc_network::DhtEvent::ValueFound(vec![(key, value)])
+	};
+
+	// Node B discovering node A's address.
 
 	let (mut dht_event_tx, dht_event_rx) = channel(1000);
-	let key_pair = AuthorityPair::from_seed_slice(&[1; 32]).unwrap();
 	let test_api = Arc::new(TestApi {
-		authorities: vec![key_pair.public()],
+		// Make sure node B identifies node A as an authority.
+		authorities: vec![node_a_public.into()],
 	});
 	let network: Arc<TestNetwork> = Arc::new(Default::default());
 	let key_store = KeyStore::new();
@@ -306,32 +331,10 @@ fn handle_dht_events_with_value_found_should_call_set_priority_group() {
 		None,
 	);
 
-	// Create sample dht event.
-
-	let authority_id_1 = hash_authority_id(key_pair.public().as_ref());
-	let address_1: Multiaddr = "/ip6/2001:db8::".parse().unwrap();
-
-	let mut serialized_addresses = vec![];
-	schema::AuthorityAddresses {
-		addresses: vec![address_1.to_vec()],
-	}
-	.encode(&mut serialized_addresses)
-	.unwrap();
-
-	let signature = key_pair.sign(serialized_addresses.as_ref()).encode();
-	let mut signed_addresses = vec![];
-	schema::SignedAuthorityAddresses {
-		addresses: serialized_addresses,
-		signature,
-	}
-	.encode(&mut signed_addresses)
-	.unwrap();
-
-	let dht_event = sc_network::DhtEvent::ValueFound(vec![(authority_id_1, signed_addresses)]);
 	dht_event_tx.try_send(dht_event).unwrap();
 
-	// Make authority discovery handle the event.
 	let f = |cx: &mut Context<'_>| -> Poll<()> {
+		// Make authority discovery handle the event.
 		if let Poll::Ready(e) = authority_discovery.handle_dht_events(cx) {
 			panic!("Unexpected error: {:?}", e);
 		}
@@ -343,7 +346,7 @@ fn handle_dht_events_with_value_found_should_call_set_priority_group() {
 			network.set_priority_group_call.lock().unwrap()[0],
 			(
 				"authorities".to_string(),
-				HashSet::from_iter(vec![address_1.clone()].into_iter())
+				HashSet::from_iter(vec![node_a_multiaddr.clone()].into_iter())
 			)
 		);
 
diff --git a/substrate/primitives/core/src/traits.rs b/substrate/primitives/core/src/traits.rs
index cca1a8fa8c..133a4a4e19 100644
--- a/substrate/primitives/core/src/traits.rs
+++ b/substrate/primitives/core/src/traits.rs
@@ -120,7 +120,7 @@ pub trait BareCryptoStore: Send + Sync {
 	/// Given a list of public keys, find the first supported key and
 	/// sign the provided message with that key.
 	///
-	/// Returns a tuple of the used key and the signature
+	/// Returns a tuple of the used key and the SCALE encoded signature.
 	fn sign_with_any(
 		&self,
 		id: KeyTypeId,
@@ -144,8 +144,8 @@ pub trait BareCryptoStore: Send + Sync {
 	/// Provided a list of public keys, sign a message with
 	/// each key given that the key is supported.
 	///
-	/// Returns a list of `Result`s each representing the signature of each key or
-	/// a BareCryptoStoreError for non-supported keys.
+	/// Returns a list of `Result`s each representing the SCALE encoded
+	/// signature of each key or a BareCryptoStoreError for non-supported keys.
 	fn sign_with_all(
 		&self,
 		id: KeyTypeId,