From a6c8ad522a55f79b862cb1a744dec0f8fb5dbcf9 Mon Sep 17 00:00:00 2001
From: Alex Chepurnoy <alex.chepurnoy@iohk.io>
Date: Fri, 2 Oct 2020 18:21:40 +0300
Subject: [PATCH 01/13] lastseen & dropconnections

---
 .../scorex/core/network/NetworkController.scala    | 14 ++++++++++++++
 .../core/network/peer/InMemoryPeerDatabase.scala   |  6 +++++-
 .../scorex/core/network/peer/PeerDatabase.scala    |  2 ++
 .../scorex/core/network/peer/PeerManager.scala     |  4 ++++
 4 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/src/main/scala/scorex/core/network/NetworkController.scala b/src/main/scala/scorex/core/network/NetworkController.scala
index 44cc2115a..9fbdc4451 100644
--- a/src/main/scala/scorex/core/network/NetworkController.scala
+++ b/src/main/scala/scorex/core/network/NetworkController.scala
@@ -80,6 +80,7 @@ class NetworkController(settings: NetworkSettings,
     case Bound(_) =>
       log.info("Successfully bound to the port " + settings.bindAddress.getPort)
       scheduleConnectionToPeer()
+      dropDeadConnections()
 
     case CommandFailed(_: Bind) =>
       log.error("Network port " + settings.bindAddress.getPort + " already in use!")
@@ -94,6 +95,7 @@ class NetworkController(settings: NetworkSettings,
         case Some(handler) => handler ! msg // forward the message to the appropriate handler for processing
         case None          => log.error(s"No handlers found for message $remote: " + spec.messageCode)
       }
+      remote.peerInfo.foreach(pi => peerManagerRef ! PeerSeen(pi))
 
     case SendToNetwork(message, sendingStrategy) =>
       filterConnections(sendingStrategy, message.spec.protocolVersion).foreach { connectedPeer =>
@@ -201,6 +203,18 @@ class NetworkController(settings: NetworkSettings,
     }
   }
 
+  private def dropDeadConnections(): Unit = {
+    context.system.scheduler.schedule(5.seconds, 15.seconds) {
+      connections.values.filter{ cp =>
+        val now = scorexContext.timeProvider.time()
+        val lastSeen = cp.peerInfo.map(_.lastSeen).getOrElse(now)
+        (now - lastSeen) > 1000 * 90
+      }.foreach { cp =>
+        cp.handlerRef ! CloseConnection
+      }
+    }
+  }
+
   /**
     * Connect to peer
     *
diff --git a/src/main/scala/scorex/core/network/peer/InMemoryPeerDatabase.scala b/src/main/scala/scorex/core/network/peer/InMemoryPeerDatabase.scala
index 54361ebac..75e4c561d 100644
--- a/src/main/scala/scorex/core/network/peer/InMemoryPeerDatabase.scala
+++ b/src/main/scala/scorex/core/network/peer/InMemoryPeerDatabase.scala
@@ -108,6 +108,11 @@ final class InMemoryPeerDatabase(settings: NetworkSettings, timeProvider: TimePr
     stillBanned
   }
 
+  override def peerSeen(peerInfo: PeerInfo): Unit = {
+    val pi = peerInfo.copy(lastSeen = timeProvider.time())
+    addOrUpdateKnownPeer(pi)
+  }
+
   private def penaltyScore(penaltyType: PenaltyType): Int =
     penaltyType match {
       case PenaltyType.NonDeliveryPenalty =>
@@ -127,5 +132,4 @@ final class InMemoryPeerDatabase(settings: NetworkSettings, timeProvider: TimePr
       case PenaltyType.PermanentPenalty =>
         (360 * 10).days.toMillis
     }
-
 }
diff --git a/src/main/scala/scorex/core/network/peer/PeerDatabase.scala b/src/main/scala/scorex/core/network/peer/PeerDatabase.scala
index ef09a0b45..05872cfe9 100644
--- a/src/main/scala/scorex/core/network/peer/PeerDatabase.scala
+++ b/src/main/scala/scorex/core/network/peer/PeerDatabase.scala
@@ -10,6 +10,8 @@ trait PeerDatabase {
 
   def addOrUpdateKnownPeer(peerInfo: PeerInfo): Unit
 
+  def peerSeen(peerInfo: PeerInfo): Unit
+
   def knownPeers: Map[InetSocketAddress, PeerInfo]
 
   def addToBlacklist(address: InetSocketAddress, penaltyType: PenaltyType): Unit
diff --git a/src/main/scala/scorex/core/network/peer/PeerManager.scala b/src/main/scala/scorex/core/network/peer/PeerManager.scala
index 082f10ad8..04f5c61d9 100644
--- a/src/main/scala/scorex/core/network/peer/PeerManager.scala
+++ b/src/main/scala/scorex/core/network/peer/PeerManager.scala
@@ -46,6 +46,8 @@ class PeerManager(settings: ScorexSettings, scorexContext: ScorexContext) extend
       // We have connected to a peer and got his peerInfo from him
       if (!isSelf(peerInfo.peerSpec)) peerDatabase.addOrUpdateKnownPeer(peerInfo)
 
+    case PeerSeen(peerInfo) => peerDatabase.peerSeen(peerInfo)
+
     case Penalize(peer, penaltyType) =>
       log.info(s"$peer penalized, penalty: $penaltyType")
       if (peerDatabase.penalize(peer, penaltyType)) {
@@ -109,6 +111,8 @@ object PeerManager {
     // peerListOperations messages
     case class AddOrUpdatePeer(data: PeerInfo)
 
+    case class PeerSeen(peerInfo: PeerInfo)
+
     case class AddPeerIfEmpty(data: PeerSpec)
 
     case class RemovePeer(address: InetSocketAddress)

From e7c4dcc68175020857387f3304209f961198251b Mon Sep 17 00:00:00 2001
From: Alex Chepurnoy <alex.chepurnoy@iohk.io>
Date: Sun, 4 Oct 2020 20:27:37 +0300
Subject: [PATCH 02/13] log messages

---
 .../scorex/core/network/NetworkController.scala  | 16 +++++++++++-----
 1 file changed, 11 insertions(+), 5 deletions(-)

diff --git a/src/main/scala/scorex/core/network/NetworkController.scala b/src/main/scala/scorex/core/network/NetworkController.scala
index 9fbdc4451..badd2ef17 100644
--- a/src/main/scala/scorex/core/network/NetworkController.scala
+++ b/src/main/scala/scorex/core/network/NetworkController.scala
@@ -90,12 +90,15 @@ class NetworkController(settings: NetworkSettings,
 
   private def businessLogic: Receive = {
     //a message coming in from another peer
-    case msg @ Message(spec, _, Some(remote)) =>
+    case msg@Message(spec, _, Some(remote)) =>
       messageHandlers.get(spec.messageCode) match {
         case Some(handler) => handler ! msg // forward the message to the appropriate handler for processing
-        case None          => log.error(s"No handlers found for message $remote: " + spec.messageCode)
+        case None => log.error(s"No handlers found for message $remote: " + spec.messageCode)
+      }
+      remote.peerInfo.foreach { pi =>
+        log.debug(s"Got a message from ${pi.peerSpec.address}, going to update last-seen")
+        peerManagerRef ! PeerSeen(pi)
       }
-      remote.peerInfo.foreach(pi => peerManagerRef ! PeerSeen(pi))
 
     case SendToNetwork(message, sendingStrategy) =>
       filterConnections(sendingStrategy, message.spec.protocolVersion).foreach { connectedPeer =>
@@ -204,12 +207,15 @@ class NetworkController(settings: NetworkSettings,
   }
 
   private def dropDeadConnections(): Unit = {
-    context.system.scheduler.schedule(5.seconds, 15.seconds) {
+    context.system.scheduler.schedule(60.seconds, 60.seconds) {
       connections.values.filter{ cp =>
         val now = scorexContext.timeProvider.time()
         val lastSeen = cp.peerInfo.map(_.lastSeen).getOrElse(now)
-        (now - lastSeen) > 1000 * 90
+        (now - lastSeen) > 1000 * 60 * 2 // 2 minutes
       }.foreach { cp =>
+        val now = scorexContext.timeProvider.time()
+        val lastSeen = cp.peerInfo.map(_.lastSeen).getOrElse(now)
+        log.info(s"Dropping connection with ${cp.peerInfo}, last seen ${(now-lastSeen) / 1000} seconds ago")
         cp.handlerRef ! CloseConnection
       }
     }

From 9fddae6433d96c6828dabe811d956f9c69c7b909 Mon Sep 17 00:00:00 2001
From: Alex Chepurnoy <alex.chepurnoy@iohk.io>
Date: Sun, 4 Oct 2020 22:06:14 +0300
Subject: [PATCH 03/13] remove peer from db only if there are enough living
 connections

---
 .../scala/scorex/core/network/NetworkController.scala     | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/main/scala/scorex/core/network/NetworkController.scala b/src/main/scala/scorex/core/network/NetworkController.scala
index badd2ef17..a7efdd4c1 100644
--- a/src/main/scala/scorex/core/network/NetworkController.scala
+++ b/src/main/scala/scorex/core/network/NetworkController.scala
@@ -155,8 +155,11 @@ class NetworkController(settings: NetworkSettings,
         case Some(t) => log.info("Failed to connect to : " + c.remoteAddress, t)
         case None => log.info("Failed to connect to : " + c.remoteAddress)
       }
-      // remove not responding peer from database
-      peerManagerRef ! RemovePeer(c.remoteAddress)
+
+      // If enough live connections, remove not responding peer from database
+      if(connections.size > settings.maxConnections / 2) {
+        peerManagerRef ! RemovePeer(c.remoteAddress)
+      }
 
     case Terminated(ref) =>
       connectionForHandler(ref).foreach { connectedPeer =>
@@ -197,6 +200,7 @@ class NetworkController(settings: NetworkSettings,
     */
   private def scheduleConnectionToPeer(): Unit = {
     context.system.scheduler.schedule(5.seconds, 5.seconds) {
+      log.info(s"Has ${connections.size} connections")
       if (connections.size < settings.maxConnections) {
         val randomPeerF = peerManagerRef ? RandomPeerExcluding(connections.values.flatMap(_.peerInfo).toSeq)
         randomPeerF.mapTo[Option[PeerInfo]].foreach { peerInfoOpt =>

From 8a49a4418339a8f1824765b6fceaace0df15131a Mon Sep 17 00:00:00 2001
From: Alex Chepurnoy <alex.chepurnoy@iohk.io>
Date: Sun, 4 Oct 2020 23:22:36 +0300
Subject: [PATCH 04/13] updating last-seen for connected peers; test

---
 .../core/network/NetworkController.scala      | 19 +++++++----
 .../network/peer/InMemoryPeerDatabase.scala   |  6 +---
 .../core/network/peer/PeerDatabase.scala      |  2 --
 .../core/network/peer/PeerManager.scala       |  4 ---
 .../network/NetworkControllerSpec.scala       | 34 ++++++++++++++++++-
 5 files changed, 47 insertions(+), 18 deletions(-)

diff --git a/src/main/scala/scorex/core/network/NetworkController.scala b/src/main/scala/scorex/core/network/NetworkController.scala
index a7efdd4c1..4913dd56b 100644
--- a/src/main/scala/scorex/core/network/NetworkController.scala
+++ b/src/main/scala/scorex/core/network/NetworkController.scala
@@ -95,9 +95,16 @@ class NetworkController(settings: NetworkSettings,
         case Some(handler) => handler ! msg // forward the message to the appropriate handler for processing
         case None => log.error(s"No handlers found for message $remote: " + spec.messageCode)
       }
-      remote.peerInfo.foreach { pi =>
-        log.debug(s"Got a message from ${pi.peerSpec.address}, going to update last-seen")
-        peerManagerRef ! PeerSeen(pi)
+
+      val remoteAddress = remote.connectionId.remoteAddress
+      connections.get(remote.connectionId.remoteAddress) match {
+        case Some(cp) => cp.peerInfo match {
+          case Some(pi) =>
+            val now = scorexContext.timeProvider.time()
+            connections += remoteAddress -> cp.copy(peerInfo = Some(pi.copy(lastSeen = now)))
+          case None => log.warn("Peer info not found for a message got from: " + remoteAddress)
+        }
+        case None => log.warn("Connection not found for a message got from: " + remoteAddress)
       }
 
     case SendToNetwork(message, sendingStrategy) =>
@@ -200,8 +207,8 @@ class NetworkController(settings: NetworkSettings,
     */
   private def scheduleConnectionToPeer(): Unit = {
     context.system.scheduler.schedule(5.seconds, 5.seconds) {
-      log.info(s"Has ${connections.size} connections")
       if (connections.size < settings.maxConnections) {
+        log.info(s"Looking for a new random connection")
         val randomPeerF = peerManagerRef ? RandomPeerExcluding(connections.values.flatMap(_.peerInfo).toSeq)
         randomPeerF.mapTo[Option[PeerInfo]].foreach { peerInfoOpt =>
           peerInfoOpt.foreach(peerInfo => self ! ConnectTo(peerInfo))
@@ -212,14 +219,14 @@ class NetworkController(settings: NetworkSettings,
 
   private def dropDeadConnections(): Unit = {
     context.system.scheduler.schedule(60.seconds, 60.seconds) {
-      connections.values.filter{ cp =>
+      connections.values.filter { cp =>
         val now = scorexContext.timeProvider.time()
         val lastSeen = cp.peerInfo.map(_.lastSeen).getOrElse(now)
         (now - lastSeen) > 1000 * 60 * 2 // 2 minutes
       }.foreach { cp =>
         val now = scorexContext.timeProvider.time()
         val lastSeen = cp.peerInfo.map(_.lastSeen).getOrElse(now)
-        log.info(s"Dropping connection with ${cp.peerInfo}, last seen ${(now-lastSeen) / 1000} seconds ago")
+        log.info(s"Dropping connection with ${cp.peerInfo}, last seen ${(now - lastSeen) / 1000} seconds ago")
         cp.handlerRef ! CloseConnection
       }
     }
diff --git a/src/main/scala/scorex/core/network/peer/InMemoryPeerDatabase.scala b/src/main/scala/scorex/core/network/peer/InMemoryPeerDatabase.scala
index 75e4c561d..673098be8 100644
--- a/src/main/scala/scorex/core/network/peer/InMemoryPeerDatabase.scala
+++ b/src/main/scala/scorex/core/network/peer/InMemoryPeerDatabase.scala
@@ -31,6 +31,7 @@ final class InMemoryPeerDatabase(settings: NetworkSettings, timeProvider: TimePr
   override def addOrUpdateKnownPeer(peerInfo: PeerInfo): Unit = {
     if (!peerInfo.peerSpec.declaredAddress.exists(x => isBlacklisted(x.getAddress))) {
       peerInfo.peerSpec.address.foreach { address =>
+        log.info(s"Updating peer info for $address")
         peers += address -> peerInfo
       }
     }
@@ -108,11 +109,6 @@ final class InMemoryPeerDatabase(settings: NetworkSettings, timeProvider: TimePr
     stillBanned
   }
 
-  override def peerSeen(peerInfo: PeerInfo): Unit = {
-    val pi = peerInfo.copy(lastSeen = timeProvider.time())
-    addOrUpdateKnownPeer(pi)
-  }
-
   private def penaltyScore(penaltyType: PenaltyType): Int =
     penaltyType match {
       case PenaltyType.NonDeliveryPenalty =>
diff --git a/src/main/scala/scorex/core/network/peer/PeerDatabase.scala b/src/main/scala/scorex/core/network/peer/PeerDatabase.scala
index 05872cfe9..ef09a0b45 100644
--- a/src/main/scala/scorex/core/network/peer/PeerDatabase.scala
+++ b/src/main/scala/scorex/core/network/peer/PeerDatabase.scala
@@ -10,8 +10,6 @@ trait PeerDatabase {
 
   def addOrUpdateKnownPeer(peerInfo: PeerInfo): Unit
 
-  def peerSeen(peerInfo: PeerInfo): Unit
-
   def knownPeers: Map[InetSocketAddress, PeerInfo]
 
   def addToBlacklist(address: InetSocketAddress, penaltyType: PenaltyType): Unit
diff --git a/src/main/scala/scorex/core/network/peer/PeerManager.scala b/src/main/scala/scorex/core/network/peer/PeerManager.scala
index 04f5c61d9..082f10ad8 100644
--- a/src/main/scala/scorex/core/network/peer/PeerManager.scala
+++ b/src/main/scala/scorex/core/network/peer/PeerManager.scala
@@ -46,8 +46,6 @@ class PeerManager(settings: ScorexSettings, scorexContext: ScorexContext) extend
       // We have connected to a peer and got his peerInfo from him
       if (!isSelf(peerInfo.peerSpec)) peerDatabase.addOrUpdateKnownPeer(peerInfo)
 
-    case PeerSeen(peerInfo) => peerDatabase.peerSeen(peerInfo)
-
     case Penalize(peer, penaltyType) =>
       log.info(s"$peer penalized, penalty: $penaltyType")
       if (peerDatabase.penalize(peer, penaltyType)) {
@@ -111,8 +109,6 @@ object PeerManager {
     // peerListOperations messages
     case class AddOrUpdatePeer(data: PeerInfo)
 
-    case class PeerSeen(peerInfo: PeerInfo)
-
     case class AddPeerIfEmpty(data: PeerSpec)
 
     case class RemovePeer(address: InetSocketAddress)
diff --git a/src/test/scala/scorex/network/NetworkControllerSpec.scala b/src/test/scala/scorex/network/NetworkControllerSpec.scala
index 7083382d0..6f041f30e 100644
--- a/src/test/scala/scorex/network/NetworkControllerSpec.scala
+++ b/src/test/scala/scorex/network/NetworkControllerSpec.scala
@@ -12,9 +12,10 @@ import org.scalatest.Matchers
 import org.scalatest.OptionValues._
 import org.scalatest.TryValues._
 import scorex.core.app.{ScorexContext, Version}
+import scorex.core.network.NetworkController.ReceivableMessages.GetConnectedPeers
 import scorex.core.network._
 import scorex.core.network.message.{PeersSpec, _}
-import scorex.core.network.peer.{LocalAddressPeerFeature, LocalAddressPeerFeatureSerializer, PeerManagerRef}
+import scorex.core.network.peer.{LocalAddressPeerFeature, LocalAddressPeerFeatureSerializer, PeerInfo, PeerManagerRef}
 import scorex.core.settings.ScorexSettings
 import scorex.core.utils.LocalTimeProvider
 
@@ -270,6 +271,37 @@ class NetworkControllerSpec extends NetworkTests {
     system.terminate()
   }
 
+  it should "update last-seen on getting message from peer" in {
+    implicit val system = ActorSystem()
+    val tcpManagerProbe = TestProbe()
+    val p = TestProbe("p")(system)
+
+    val nodeAddr = new InetSocketAddress("88.77.66.55", 12345)
+    val settings2 = settings.copy(network = settings.network.copy(bindAddress = nodeAddr))
+    val networkControllerRef: ActorRef = createNetworkController(settings2, tcpManagerProbe)
+
+    val testPeer = new TestPeer(settings2, networkControllerRef, tcpManagerProbe)
+    val peerAddr = new InetSocketAddress("88.77.66.55", 5678)
+
+    testPeer.connect(peerAddr, nodeAddr)
+    testPeer.receiveHandshake
+    testPeer.sendHandshake(Some(peerAddr), None)
+
+    p.send(networkControllerRef, GetConnectedPeers)
+    val data0 = p.expectMsgClass(classOf[Seq[PeerInfo]])
+    val ls0 = data0(0).lastSeen
+
+    Thread.sleep(1000)
+    testPeer.sendGetPeers()
+    p.send(networkControllerRef, GetConnectedPeers)
+    val data = p.expectMsgClass(classOf[Seq[PeerInfo]])
+    val ls = data(0).lastSeen
+
+    ls should not be ls0
+
+    system.terminate()
+  }
+
   private def extractLocalAddrFeat(handshakeFromNode: Handshake): Option[InetSocketAddress] = {
     handshakeFromNode.peerSpec.localAddressOpt
   }

From 9f070a8b261c92807b1664754732d0e140d53fe5 Mon Sep 17 00:00:00 2001
From: Alex Chepurnoy <alex.chepurnoy@iohk.io>
Date: Mon, 5 Oct 2020 09:52:09 +0300
Subject: [PATCH 05/13] fix for RecentlySeenPeers

---
 src/main/scala/scorex/core/network/peer/PeerManager.scala | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/main/scala/scorex/core/network/peer/PeerManager.scala b/src/main/scala/scorex/core/network/peer/PeerManager.scala
index 082f10ad8..67b83403c 100644
--- a/src/main/scala/scorex/core/network/peer/PeerManager.scala
+++ b/src/main/scala/scorex/core/network/peer/PeerManager.scala
@@ -58,6 +58,7 @@ class PeerManager(settings: ScorexSettings, scorexContext: ScorexContext) extend
       // We have received peer data from other peers. It might be modified and should not affect existing data if any
       if (peerSpec.address.forall(a => peerDatabase.get(a).isEmpty) && !isSelf(peerSpec)) {
         val peerInfo: PeerInfo = PeerInfo(peerSpec, 0, None)
+        log.info(s"New discovered peer: $peerInfo")
         peerDatabase.addOrUpdateKnownPeer(peerInfo)
       }
 
@@ -127,15 +128,13 @@ object PeerManager {
       * were connected in at most 1 hour ago and weren't blacklisted.
       */
     case class RecentlySeenPeers(howMany: Int) extends GetPeers[Seq[PeerInfo]] {
-      private val TimeDiff: Long = 60 * 60 * 1000
 
       override def choose(knownPeers: Map[InetSocketAddress, PeerInfo],
                           blacklistedPeers: Seq[InetAddress],
                           sc: ScorexContext): Seq[PeerInfo] = {
-        val currentTime = sc.timeProvider.time()
         val recentlySeenNonBlacklisted = knownPeers.values.toSeq
           .filter { p =>
-            (p.connectionType.isDefined || currentTime - p.lastSeen > TimeDiff) &&
+            (p.connectionType.isDefined || p.lastSeen > 0) &&
               !blacklistedPeers.exists(ip => p.peerSpec.declaredAddress.exists(_.getAddress == ip))
           }
         Random.shuffle(recentlySeenNonBlacklisted).take(howMany)

From 102e2d491d0ffb24a4c876ddca56f8f9beb95b96 Mon Sep 17 00:00:00 2001
From: Konstantin Knizhnik <knizhnik@garret.ru>
Date: Sun, 11 Oct 2020 22:08:05 +0300
Subject: [PATCH 06/13] Add peers/status method

---
 .../scorex/core/api/http/PeersApiRoute.scala  | 19 +++++++++++++++----
 .../core/network/NetworkController.scala      | 10 +++++++++-
 .../scorex/core/network/peer/PeerInfo.scala   |  8 ++++++++
 3 files changed, 32 insertions(+), 5 deletions(-)

diff --git a/src/main/scala/scorex/core/api/http/PeersApiRoute.scala b/src/main/scala/scorex/core/api/http/PeersApiRoute.scala
index 2273fe141..ac38dc0e7 100644
--- a/src/main/scala/scorex/core/api/http/PeersApiRoute.scala
+++ b/src/main/scala/scorex/core/api/http/PeersApiRoute.scala
@@ -7,9 +7,9 @@ import akka.http.scaladsl.server.Route
 import io.circe.generic.semiauto._
 import io.circe.syntax._
 import io.circe.{Encoder, Json}
-import scorex.core.api.http.PeersApiRoute.{BlacklistedPeers, PeerInfoResponse}
-import scorex.core.network.NetworkController.ReceivableMessages.{ConnectTo, GetConnectedPeers}
-import scorex.core.network.peer.PeerInfo
+import scorex.core.api.http.PeersApiRoute.{BlacklistedPeers, PeerInfoResponse, PeersStatusResponse}
+import scorex.core.network.NetworkController.ReceivableMessages.{ConnectTo, GetConnectedPeers, GetPeersStatus}
+import scorex.core.network.peer.{PeerInfo, PeersStatus}
 import scorex.core.network.peer.PeerManager.ReceivableMessages.{GetAllPeers, GetBlacklistedPeers}
 import scorex.core.settings.RESTApiSettings
 import scorex.core.utils.NetworkTimeProvider
@@ -23,7 +23,7 @@ case class PeersApiRoute(peerManager: ActorRef,
                         (implicit val context: ActorRefFactory, val ec: ExecutionContext) extends ApiRoute {
 
   override lazy val route: Route = pathPrefix("peers") {
-    allPeers ~ connectedPeers ~ blacklistedPeers ~ connect
+    allPeers ~ connectedPeers ~ blacklistedPeers ~ connect ~ peersStatus
   }
 
   def allPeers: Route = (path("all") & get) {
@@ -49,6 +49,13 @@ case class PeersApiRoute(peerManager: ActorRef,
     ApiResponse(result)
   }
 
+  def peersStatus: Route  = (path("status") & get) {
+    val result = askActor[PeersStatus](networkController, GetPeersStatus).map {
+      case PeersStatus(lastIncomingMessage,currentNetworkTime) => PeersStatusResponse(lastIncomingMessage,currentNetworkTime)
+    }
+    ApiResponse(result)
+  }
+
   private val addressAndPortRegexp = "([\\w\\.]+):(\\d{1,5})".r
 
   def connect: Route = (path("connect") & post & withAuth & entity(as[Json])) { json =>
@@ -88,6 +95,8 @@ object PeersApiRoute {
     )
   }
 
+  case class PeersStatusResponse(lastIncomingMessage: Long, currentSystemTime: Long)
+
   case class BlacklistedPeers(addresses: Seq[String])
 
   @SuppressWarnings(Array("org.wartremover.warts.PublicInference"))
@@ -96,5 +105,7 @@ object PeersApiRoute {
   @SuppressWarnings(Array("org.wartremover.warts.PublicInference"))
   implicit val encodeBlackListedPeers: Encoder[BlacklistedPeers] = deriveEncoder
 
+  @SuppressWarnings(Array("org.wartremover.warts.PublicInference"))
+  implicit val encodePeersStatusResponse: Encoder[PeersStatusResponse] = deriveEncoder
 }
 
diff --git a/src/main/scala/scorex/core/network/NetworkController.scala b/src/main/scala/scorex/core/network/NetworkController.scala
index 4913dd56b..72fcd9fe3 100644
--- a/src/main/scala/scorex/core/network/NetworkController.scala
+++ b/src/main/scala/scorex/core/network/NetworkController.scala
@@ -7,6 +7,7 @@ import akka.io.Tcp._
 import akka.io.{IO, Tcp}
 import akka.pattern.ask
 import akka.util.Timeout
+import scorex.core.api.http.PeersApiRoute.PeersStatusResponse
 import scorex.core.app.{ScorexContext, Version}
 import scorex.core.network.NodeViewSynchronizer.ReceivableMessages.{DisconnectedPeer, HandshakedPeer}
 import scorex.core.network.message.Message.MessageCode
@@ -14,7 +15,7 @@ import scorex.core.network.message.{Message, MessageSpec}
 import scorex.core.network.peer.PeerManager.ReceivableMessages._
 import scorex.core.network.peer.{LocalAddressPeerFeature, PeerInfo, PeerManager, PenaltyType}
 import scorex.core.settings.NetworkSettings
-import scorex.core.utils.NetworkUtils
+import scorex.core.utils.{NetworkUtils, TimeProvider}
 import scorex.util.ScorexLogging
 
 import scala.concurrent.ExecutionContext
@@ -60,6 +61,8 @@ class NetworkController(settings: NetworkSettings,
   private var connections = Map.empty[InetSocketAddress, ConnectedPeer]
   private var unconfirmedConnections = Set.empty[InetSocketAddress]
 
+  private var lastIncomingMessage : TimeProvider.Time = 0
+
   //check own declared address for validity
   validateDeclaredAddress()
 
@@ -101,6 +104,7 @@ class NetworkController(settings: NetworkSettings,
         case Some(cp) => cp.peerInfo match {
           case Some(pi) =>
             val now = scorexContext.timeProvider.time()
+            lastIncomingMessage = now
             connections += remoteAddress -> cp.copy(peerInfo = Some(pi.copy(lastSeen = now)))
           case None => log.warn("Peer info not found for a message got from: " + remoteAddress)
         }
@@ -182,6 +186,9 @@ class NetworkController(settings: NetworkSettings,
 
   //calls from API / application
   private def interfaceCalls: Receive = {
+    case GetPeersStatus =>
+      sender() ! PeersStatusResponse(lastIncomingMessage, scorexContext.timeProvider.time())
+
     case GetConnectedPeers =>
       sender() ! connections.values.flatMap(_.peerInfo).toSeq
 
@@ -474,6 +481,7 @@ object NetworkController {
 
     case object GetConnectedPeers
 
+    case object GetPeersStatus
   }
 
 }
diff --git a/src/main/scala/scorex/core/network/peer/PeerInfo.scala b/src/main/scala/scorex/core/network/peer/PeerInfo.scala
index b504d2638..f6aa92da6 100644
--- a/src/main/scala/scorex/core/network/peer/PeerInfo.scala
+++ b/src/main/scala/scorex/core/network/peer/PeerInfo.scala
@@ -16,6 +16,14 @@ case class PeerInfo(peerSpec: PeerSpec,
                     lastSeen: Long,
                     connectionType: Option[ConnectionDirection] = None)
 
+/**
+  * Information about all peers
+  *
+  * @param lastIncomingMessage - timestamp of last received message from any peer
+  * @param currentNetworkTime  - current network time
+  */
+case class PeersStatus(lastIncomingMessage: Long, currentNetworkTime: Long)
+
 object PeerInfo {
 
   /**

From a05971e4cdefb13675c4f43a8b760301e2e5ef67 Mon Sep 17 00:00:00 2001
From: Alex Chepurnoy <alex.chepurnoy@iohk.io>
Date: Thu, 15 Oct 2020 16:40:04 +0300
Subject: [PATCH 07/13] RecentlySeenPeers comments fixed

---
 src/main/scala/scorex/core/api/http/PeersApiRoute.scala   | 4 ++++
 src/main/scala/scorex/core/network/peer/PeerInfo.scala    | 2 +-
 src/main/scala/scorex/core/network/peer/PeerManager.scala | 5 +++--
 3 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/src/main/scala/scorex/core/api/http/PeersApiRoute.scala b/src/main/scala/scorex/core/api/http/PeersApiRoute.scala
index ac38dc0e7..45e440f3b 100644
--- a/src/main/scala/scorex/core/api/http/PeersApiRoute.scala
+++ b/src/main/scala/scorex/core/api/http/PeersApiRoute.scala
@@ -49,6 +49,10 @@ case class PeersApiRoute(peerManager: ActorRef,
     ApiResponse(result)
   }
 
+  /**
+    * Get status of P2P layer
+    * @return time of last incoming message and network time (got from NTP server)
+    */
   def peersStatus: Route  = (path("status") & get) {
     val result = askActor[PeersStatus](networkController, GetPeersStatus).map {
       case PeersStatus(lastIncomingMessage,currentNetworkTime) => PeersStatusResponse(lastIncomingMessage,currentNetworkTime)
diff --git a/src/main/scala/scorex/core/network/peer/PeerInfo.scala b/src/main/scala/scorex/core/network/peer/PeerInfo.scala
index f6aa92da6..a8aede604 100644
--- a/src/main/scala/scorex/core/network/peer/PeerInfo.scala
+++ b/src/main/scala/scorex/core/network/peer/PeerInfo.scala
@@ -17,7 +17,7 @@ case class PeerInfo(peerSpec: PeerSpec,
                     connectionType: Option[ConnectionDirection] = None)
 
 /**
-  * Information about all peers
+  * Information about P2P layer status
   *
   * @param lastIncomingMessage - timestamp of last received message from any peer
   * @param currentNetworkTime  - current network time
diff --git a/src/main/scala/scorex/core/network/peer/PeerManager.scala b/src/main/scala/scorex/core/network/peer/PeerManager.scala
index 67b83403c..1b19eba66 100644
--- a/src/main/scala/scorex/core/network/peer/PeerManager.scala
+++ b/src/main/scala/scorex/core/network/peer/PeerManager.scala
@@ -124,8 +124,9 @@ object PeerManager {
     }
 
     /**
-      * Choose at most `howMany` random peers, which are connected to our peer or
-      * were connected in at most 1 hour ago and weren't blacklisted.
+      * Choose at most `howMany` random peers, which were connected to our peer and weren't blacklisted.
+      *
+      * Used in peer propagation: peers chosen are recommended to a peer asking our node about more peers.
       */
     case class RecentlySeenPeers(howMany: Int) extends GetPeers[Seq[PeerInfo]] {
 

From b9ab7aebbb619956207ceb059c9dfbe7277f506b Mon Sep 17 00:00:00 2001
From: Alex Chepurnoy <alex.chepurnoy@iohk.io>
Date: Thu, 15 Oct 2020 17:06:28 +0300
Subject: [PATCH 08/13] last-seen test improved

---
 .../scala/scorex/core/api/http/PeersApiRoute.scala  |  6 ++++--
 .../scorex/core/network/peer/PeerDatabase.scala     |  4 ++++
 .../scorex/network/NetworkControllerSpec.scala      | 13 +++++++++----
 3 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/src/main/scala/scorex/core/api/http/PeersApiRoute.scala b/src/main/scala/scorex/core/api/http/PeersApiRoute.scala
index 45e440f3b..1b86c46c8 100644
--- a/src/main/scala/scorex/core/api/http/PeersApiRoute.scala
+++ b/src/main/scala/scorex/core/api/http/PeersApiRoute.scala
@@ -51,11 +51,13 @@ case class PeersApiRoute(peerManager: ActorRef,
 
   /**
     * Get status of P2P layer
+    *
     * @return time of last incoming message and network time (got from NTP server)
     */
-  def peersStatus: Route  = (path("status") & get) {
+  def peersStatus: Route = (path("status") & get) {
     val result = askActor[PeersStatus](networkController, GetPeersStatus).map {
-      case PeersStatus(lastIncomingMessage,currentNetworkTime) => PeersStatusResponse(lastIncomingMessage,currentNetworkTime)
+      case PeersStatus(lastIncomingMessage, currentNetworkTime) =>
+        PeersStatusResponse(lastIncomingMessage, currentNetworkTime)
     }
     ApiResponse(result)
   }
diff --git a/src/main/scala/scorex/core/network/peer/PeerDatabase.scala b/src/main/scala/scorex/core/network/peer/PeerDatabase.scala
index ef09a0b45..7cdead342 100644
--- a/src/main/scala/scorex/core/network/peer/PeerDatabase.scala
+++ b/src/main/scala/scorex/core/network/peer/PeerDatabase.scala
@@ -8,6 +8,10 @@ trait PeerDatabase {
 
   def isEmpty: Boolean
 
+  /**
+    * Add peer to the database, or update it
+    * @param peerInfo - peer record
+    */
   def addOrUpdateKnownPeer(peerInfo: PeerInfo): Unit
 
   def knownPeers: Map[InetSocketAddress, PeerInfo]
diff --git a/src/test/scala/scorex/network/NetworkControllerSpec.scala b/src/test/scala/scorex/network/NetworkControllerSpec.scala
index 6f041f30e..a2fe05a7f 100644
--- a/src/test/scala/scorex/network/NetworkControllerSpec.scala
+++ b/src/test/scala/scorex/network/NetworkControllerSpec.scala
@@ -11,11 +11,12 @@ import org.scalatest.EitherValues._
 import org.scalatest.Matchers
 import org.scalatest.OptionValues._
 import org.scalatest.TryValues._
+import scorex.core.api.http.PeersApiRoute.PeersStatusResponse
 import scorex.core.app.{ScorexContext, Version}
-import scorex.core.network.NetworkController.ReceivableMessages.GetConnectedPeers
+import scorex.core.network.NetworkController.ReceivableMessages.{GetConnectedPeers, GetPeersStatus}
 import scorex.core.network._
 import scorex.core.network.message.{PeersSpec, _}
-import scorex.core.network.peer.{LocalAddressPeerFeature, LocalAddressPeerFeatureSerializer, PeerInfo, PeerManagerRef}
+import scorex.core.network.peer.{LocalAddressPeerFeature, LocalAddressPeerFeatureSerializer, PeerInfo, PeerManagerRef, PeersStatus}
 import scorex.core.settings.ScorexSettings
 import scorex.core.utils.LocalTimeProvider
 
@@ -292,13 +293,17 @@ class NetworkControllerSpec extends NetworkTests {
     val ls0 = data0(0).lastSeen
 
     Thread.sleep(1000)
-    testPeer.sendGetPeers()
+    testPeer.sendGetPeers() // send a message to see node's status update then
+
     p.send(networkControllerRef, GetConnectedPeers)
     val data = p.expectMsgClass(classOf[Seq[PeerInfo]])
     val ls = data(0).lastSeen
-
     ls should not be ls0
 
+    p.send(networkControllerRef, GetPeersStatus)
+    val status = p.expectMsgClass(classOf[PeersStatusResponse])
+    status.lastIncomingMessage shouldBe ls
+
     system.terminate()
   }
 

From f920be38b58b899fe5d87addc5bdbb6a177a1f7d Mon Sep 17 00:00:00 2001
From: Alex Chepurnoy <alex.chepurnoy@iohk.io>
Date: Thu, 15 Oct 2020 18:20:39 +0300
Subject: [PATCH 09/13] conectivity, flexible disconnecting time

---
 .../core/network/NetworkController.scala      | 40 +++++++++++++------
 1 file changed, 28 insertions(+), 12 deletions(-)

diff --git a/src/main/scala/scorex/core/network/NetworkController.scala b/src/main/scala/scorex/core/network/NetworkController.scala
index 72fcd9fe3..96fac41da 100644
--- a/src/main/scala/scorex/core/network/NetworkController.scala
+++ b/src/main/scala/scorex/core/network/NetworkController.scala
@@ -15,6 +15,7 @@ import scorex.core.network.message.{Message, MessageSpec}
 import scorex.core.network.peer.PeerManager.ReceivableMessages._
 import scorex.core.network.peer.{LocalAddressPeerFeature, PeerInfo, PeerManager, PenaltyType}
 import scorex.core.settings.NetworkSettings
+import scorex.core.utils.TimeProvider.Time
 import scorex.core.utils.{NetworkUtils, TimeProvider}
 import scorex.util.ScorexLogging
 
@@ -61,7 +62,11 @@ class NetworkController(settings: NetworkSettings,
   private var connections = Map.empty[InetSocketAddress, ConnectedPeer]
   private var unconfirmedConnections = Set.empty[InetSocketAddress]
 
-  private var lastIncomingMessage : TimeProvider.Time = 0
+  /**
+    * Storing timestamp of a last message got via p2p network.
+    * Used to check whether connectivity is lost.
+    */
+  private var lastIncomingMessageTime : TimeProvider.Time = 0L
 
   //check own declared address for validity
   validateDeclaredAddress()
@@ -91,6 +96,14 @@ class NetworkController(settings: NetworkSettings,
       context stop self
   }
 
+  def networkTime(): Time = scorexContext.timeProvider.time()
+
+  // Checks that connectivity is not lost
+  private def connectivity: Boolean = {
+    connections.nonEmpty &&
+      networkTime() < (lastIncomingMessageTime + settings.syncStatusRefreshStable.toMillis)
+  }
+
   private def businessLogic: Receive = {
     //a message coming in from another peer
     case msg@Message(spec, _, Some(remote)) =>
@@ -103,8 +116,8 @@ class NetworkController(settings: NetworkSettings,
       connections.get(remote.connectionId.remoteAddress) match {
         case Some(cp) => cp.peerInfo match {
           case Some(pi) =>
-            val now = scorexContext.timeProvider.time()
-            lastIncomingMessage = now
+            val now = networkTime()
+            lastIncomingMessageTime = now
             connections += remoteAddress -> cp.copy(peerInfo = Some(pi.copy(lastSeen = now)))
           case None => log.warn("Peer info not found for a message got from: " + remoteAddress)
         }
@@ -168,6 +181,7 @@ class NetworkController(settings: NetworkSettings,
       }
 
       // If enough live connections, remove not responding peer from database
+      // In not enough live connections, maybe connectivity lost but the node has not updated its status, no ban then
       if(connections.size > settings.maxConnections / 2) {
         peerManagerRef ! RemovePeer(c.remoteAddress)
       }
@@ -187,7 +201,7 @@ class NetworkController(settings: NetworkSettings,
   //calls from API / application
   private def interfaceCalls: Receive = {
     case GetPeersStatus =>
-      sender() ! PeersStatusResponse(lastIncomingMessage, scorexContext.timeProvider.time())
+      sender() ! PeersStatusResponse(lastIncomingMessageTime, networkTime())
 
     case GetConnectedPeers =>
       sender() ! connections.values.flatMap(_.peerInfo).toSeq
@@ -226,15 +240,14 @@ class NetworkController(settings: NetworkSettings,
 
   private def dropDeadConnections(): Unit = {
     context.system.scheduler.schedule(60.seconds, 60.seconds) {
-      connections.values.filter { cp =>
-        val now = scorexContext.timeProvider.time()
-        val lastSeen = cp.peerInfo.map(_.lastSeen).getOrElse(now)
-        (now - lastSeen) > 1000 * 60 * 2 // 2 minutes
-      }.foreach { cp =>
-        val now = scorexContext.timeProvider.time()
+      // Drop connections with peers if they seem to be inactive
+      val now = networkTime()
+      connections.values.foreach { cp =>
         val lastSeen = cp.peerInfo.map(_.lastSeen).getOrElse(now)
-        log.info(s"Dropping connection with ${cp.peerInfo}, last seen ${(now - lastSeen) / 1000} seconds ago")
-        cp.handlerRef ! CloseConnection
+        if ((now - lastSeen) > settings.syncStatusRefreshStable.toMillis) {
+          log.info(s"Dropping connection with ${cp.peerInfo}, last seen ${(now - lastSeen) / 1000} seconds ago")
+          cp.handlerRef ! CloseConnection
+        }
       }
     }
   }
@@ -481,6 +494,9 @@ object NetworkController {
 
     case object GetConnectedPeers
 
+    /**
+      * Get p2p network status
+      */
     case object GetPeersStatus
   }
 

From 09df1d40a61a990ac0ef7c8348c8dd684650b3d1 Mon Sep 17 00:00:00 2001
From: Alex Chepurnoy <alex.chepurnoy@iohk.io>
Date: Sat, 17 Oct 2020 00:32:51 +0300
Subject: [PATCH 10/13] global connectivity check removed

---
 .../scorex/core/network/NetworkController.scala     | 13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)

diff --git a/src/main/scala/scorex/core/network/NetworkController.scala b/src/main/scala/scorex/core/network/NetworkController.scala
index 96fac41da..7ce4f0f4b 100644
--- a/src/main/scala/scorex/core/network/NetworkController.scala
+++ b/src/main/scala/scorex/core/network/NetworkController.scala
@@ -88,7 +88,7 @@ class NetworkController(settings: NetworkSettings,
     case Bound(_) =>
       log.info("Successfully bound to the port " + settings.bindAddress.getPort)
       scheduleConnectionToPeer()
-      dropDeadConnections()
+      scheduleDroppingDeadConnections()
 
     case CommandFailed(_: Bind) =>
       log.error("Network port " + settings.bindAddress.getPort + " already in use!")
@@ -98,12 +98,6 @@ class NetworkController(settings: NetworkSettings,
 
   def networkTime(): Time = scorexContext.timeProvider.time()
 
-  // Checks that connectivity is not lost
-  private def connectivity: Boolean = {
-    connections.nonEmpty &&
-      networkTime() < (lastIncomingMessageTime + settings.syncStatusRefreshStable.toMillis)
-  }
-
   private def businessLogic: Receive = {
     //a message coming in from another peer
     case msg@Message(spec, _, Some(remote)) =>
@@ -238,7 +232,10 @@ class NetworkController(settings: NetworkSettings,
     }
   }
 
-  private def dropDeadConnections(): Unit = {
+  /**
+    * Schedule a periodic dropping of connections which seem to be inactive
+    */
+  private def scheduleDroppingDeadConnections(): Unit = {
     context.system.scheduler.schedule(60.seconds, 60.seconds) {
       // Drop connections with peers if they seem to be inactive
       val now = networkTime()

From 53efc6577666dc7cc82cbaf553e6842472cc2085 Mon Sep 17 00:00:00 2001
From: Alex Chepurnoy <alex.chepurnoy@iohk.io>
Date: Wed, 21 Oct 2020 22:56:21 +0300
Subject: [PATCH 11/13] final edits

---
 .../scorex/core/network/NetworkController.scala  | 16 +++++++++++-----
 .../scorex/core/network/PeerSynchronizer.scala   |  4 ++--
 .../core/network/peer/InMemoryPeerDatabase.scala |  3 ++-
 .../scorex/core/network/peer/PeerManager.scala   |  2 +-
 .../scorex/network/NetworkControllerSpec.scala   |  1 +
 5 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/src/main/scala/scorex/core/network/NetworkController.scala b/src/main/scala/scorex/core/network/NetworkController.scala
index 7ce4f0f4b..cae5d3252 100644
--- a/src/main/scala/scorex/core/network/NetworkController.scala
+++ b/src/main/scala/scorex/core/network/NetworkController.scala
@@ -96,7 +96,7 @@ class NetworkController(settings: NetworkSettings,
       context stop self
   }
 
-  def networkTime(): Time = scorexContext.timeProvider.time()
+  private def networkTime(): Time = scorexContext.timeProvider.time()
 
   private def businessLogic: Receive = {
     //a message coming in from another peer
@@ -106,6 +106,7 @@ class NetworkController(settings: NetworkSettings,
         case None => log.error(s"No handlers found for message $remote: " + spec.messageCode)
       }
 
+      // Update last seen message timestamps, global and peer's, with the message timestamp
       val remoteAddress = remote.connectionId.remoteAddress
       connections.get(remote.connectionId.remoteAddress) match {
         case Some(cp) => cp.peerInfo match {
@@ -113,7 +114,8 @@ class NetworkController(settings: NetworkSettings,
             val now = networkTime()
             lastIncomingMessageTime = now
             connections += remoteAddress -> cp.copy(peerInfo = Some(pi.copy(lastSeen = now)))
-          case None => log.warn("Peer info not found for a message got from: " + remoteAddress)
+          case None =>
+            log.warn("Peer info not found for a message got from: " + remoteAddress)
         }
         case None => log.warn("Connection not found for a message got from: " + remoteAddress)
       }
@@ -223,7 +225,7 @@ class NetworkController(settings: NetworkSettings,
   private def scheduleConnectionToPeer(): Unit = {
     context.system.scheduler.schedule(5.seconds, 5.seconds) {
       if (connections.size < settings.maxConnections) {
-        log.info(s"Looking for a new random connection")
+        log.debug(s"Looking for a new random connection")
         val randomPeerF = peerManagerRef ? RandomPeerExcluding(connections.values.flatMap(_.peerInfo).toSeq)
         randomPeerF.mapTo[Option[PeerInfo]].foreach { peerInfoOpt =>
           peerInfoOpt.foreach(peerInfo => self ! ConnectTo(peerInfo))
@@ -241,8 +243,12 @@ class NetworkController(settings: NetworkSettings,
       val now = networkTime()
       connections.values.foreach { cp =>
         val lastSeen = cp.peerInfo.map(_.lastSeen).getOrElse(now)
-        if ((now - lastSeen) > settings.syncStatusRefreshStable.toMillis) {
-          log.info(s"Dropping connection with ${cp.peerInfo}, last seen ${(now - lastSeen) / 1000} seconds ago")
+        // A peer should send out sync message to us at least once per settings.syncStatusRefreshStable duration.
+        // We wait for more, namely settings.syncStatusRefreshStable.toMillis * 2
+        val timeout = settings.syncStatusRefreshStable.toMillis * 2
+        val delta = now - lastSeen
+        if (delta > timeout) {
+          log.info(s"Dropping connection with ${cp.peerInfo}, last seen ${delta / 1000.0} seconds ago")
           cp.handlerRef ! CloseConnection
         }
       }
diff --git a/src/main/scala/scorex/core/network/PeerSynchronizer.scala b/src/main/scala/scorex/core/network/PeerSynchronizer.scala
index 98cbce998..43704c080 100644
--- a/src/main/scala/scorex/core/network/PeerSynchronizer.scala
+++ b/src/main/scala/scorex/core/network/PeerSynchronizer.scala
@@ -6,7 +6,7 @@ import akka.util.Timeout
 import scorex.core.network.NetworkController.ReceivableMessages.{PenalizePeer, RegisterMessageSpecs, SendToNetwork}
 import scorex.core.network.message.{GetPeersSpec, Message, MessageSpec, PeersSpec}
 import scorex.core.network.peer.{PeerInfo, PenaltyType}
-import scorex.core.network.peer.PeerManager.ReceivableMessages.{AddPeerIfEmpty, RecentlySeenPeers}
+import scorex.core.network.peer.PeerManager.ReceivableMessages.{AddPeerIfEmpty, SeenPeers}
 import scorex.core.settings.NetworkSettings
 import scorex.util.ScorexLogging
 import shapeless.syntax.typeable._
@@ -74,7 +74,7 @@ class PeerSynchronizer(val networkControllerRef: ActorRef,
     * @param remote the remote peer to be informed of our local peers
     */
   private def gossipPeers ( remote: ConnectedPeer ): Unit =
-    (peerManager ? RecentlySeenPeers(settings.maxPeerSpecObjects))
+    (peerManager ? SeenPeers(settings.maxPeerSpecObjects))
       .mapTo[Seq[PeerInfo]]
       .foreach
       { peers =>
diff --git a/src/main/scala/scorex/core/network/peer/InMemoryPeerDatabase.scala b/src/main/scala/scorex/core/network/peer/InMemoryPeerDatabase.scala
index 673098be8..e25da6d0c 100644
--- a/src/main/scala/scorex/core/network/peer/InMemoryPeerDatabase.scala
+++ b/src/main/scala/scorex/core/network/peer/InMemoryPeerDatabase.scala
@@ -31,7 +31,7 @@ final class InMemoryPeerDatabase(settings: NetworkSettings, timeProvider: TimePr
   override def addOrUpdateKnownPeer(peerInfo: PeerInfo): Unit = {
     if (!peerInfo.peerSpec.declaredAddress.exists(x => isBlacklisted(x.getAddress))) {
       peerInfo.peerSpec.address.foreach { address =>
-        log.info(s"Updating peer info for $address")
+        log.debug(s"Updating peer info for $address")
         peers += address -> peerInfo
       }
     }
@@ -128,4 +128,5 @@ final class InMemoryPeerDatabase(settings: NetworkSettings, timeProvider: TimePr
       case PenaltyType.PermanentPenalty =>
         (360 * 10).days.toMillis
     }
+
 }
diff --git a/src/main/scala/scorex/core/network/peer/PeerManager.scala b/src/main/scala/scorex/core/network/peer/PeerManager.scala
index 1b19eba66..ec79dbf8f 100644
--- a/src/main/scala/scorex/core/network/peer/PeerManager.scala
+++ b/src/main/scala/scorex/core/network/peer/PeerManager.scala
@@ -128,7 +128,7 @@ object PeerManager {
       *
       * Used in peer propagation: peers chosen are recommended to a peer asking our node about more peers.
       */
-    case class RecentlySeenPeers(howMany: Int) extends GetPeers[Seq[PeerInfo]] {
+    case class SeenPeers(howMany: Int) extends GetPeers[Seq[PeerInfo]] {
 
       override def choose(knownPeers: Map[InetSocketAddress, PeerInfo],
                           blacklistedPeers: Seq[InetAddress],
diff --git a/src/test/scala/scorex/network/NetworkControllerSpec.scala b/src/test/scala/scorex/network/NetworkControllerSpec.scala
index a2fe05a7f..5c3629a51 100644
--- a/src/test/scala/scorex/network/NetworkControllerSpec.scala
+++ b/src/test/scala/scorex/network/NetworkControllerSpec.scala
@@ -478,4 +478,5 @@ class TestPeer(settings: ScorexSettings, networkControllerRef: ActorRef, tcpMana
         messagesSerializer.deserialize(b, None).success.value.value
     }
   }
+
 }

From 113e14b65f4d335c353c06c3e6b19039b14f50e8 Mon Sep 17 00:00:00 2001
From: Alexander Chepurnoy <alex.chepurnoy@iohk.io>
Date: Thu, 22 Oct 2020 10:39:06 +0300
Subject: [PATCH 12/13] Update
 src/main/scala/scorex/core/network/NetworkController.scala

Co-authored-by: Alexander Slesarenko <aslesarenko@users.noreply.github.com>
---
 src/main/scala/scorex/core/network/NetworkController.scala | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/main/scala/scorex/core/network/NetworkController.scala b/src/main/scala/scorex/core/network/NetworkController.scala
index cae5d3252..0530662c2 100644
--- a/src/main/scala/scorex/core/network/NetworkController.scala
+++ b/src/main/scala/scorex/core/network/NetworkController.scala
@@ -108,7 +108,7 @@ class NetworkController(settings: NetworkSettings,
 
       // Update last seen message timestamps, global and peer's, with the message timestamp
       val remoteAddress = remote.connectionId.remoteAddress
-      connections.get(remote.connectionId.remoteAddress) match {
+      connections.get(remoteAddress) match {
         case Some(cp) => cp.peerInfo match {
           case Some(pi) =>
             val now = networkTime()
@@ -543,4 +543,4 @@ object NetworkControllerRef {
       props(settings, peerManagerRef, scorexContext, IO(Tcp)),
       name)
   }
-}
\ No newline at end of file
+}

From c1733b2f12eaa5e738dc53aa5cbc7529e59b9245 Mon Sep 17 00:00:00 2001
From: Alex Chepurnoy <alex.chepurnoy@iohk.io>
Date: Thu, 22 Oct 2020 10:41:26 +0300
Subject: [PATCH 13/13] syncStatusRefreshStable.toMillis * 3

---
 src/main/scala/scorex/core/network/NetworkController.scala | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/main/scala/scorex/core/network/NetworkController.scala b/src/main/scala/scorex/core/network/NetworkController.scala
index cae5d3252..ed72ff439 100644
--- a/src/main/scala/scorex/core/network/NetworkController.scala
+++ b/src/main/scala/scorex/core/network/NetworkController.scala
@@ -244,8 +244,8 @@ class NetworkController(settings: NetworkSettings,
       connections.values.foreach { cp =>
         val lastSeen = cp.peerInfo.map(_.lastSeen).getOrElse(now)
         // A peer should send out sync message to us at least once per settings.syncStatusRefreshStable duration.
-        // We wait for more, namely settings.syncStatusRefreshStable.toMillis * 2
-        val timeout = settings.syncStatusRefreshStable.toMillis * 2
+        // We wait for more, namely settings.syncStatusRefreshStable.toMillis * 3
+        val timeout = settings.syncStatusRefreshStable.toMillis * 3
         val delta = now - lastSeen
         if (delta > timeout) {
           log.info(s"Dropping connection with ${cp.peerInfo}, last seen ${delta / 1000.0} seconds ago")