diff --git a/libethereum/PeerNetwork.cpp b/libethereum/PeerNetwork.cpp
index 850440dac..3299710e2 100644
--- a/libethereum/PeerNetwork.cpp
+++ b/libethereum/PeerNetwork.cpp
@@ -24,6 +24,15 @@
 using namespace std;
 using namespace eth;
 
+PeerSession::PeerSession(bi::tcp::socket _socket, uint _rNId): m_socket(std::move(_socket)), m_reqNetworkId(_rNId)
+{
+}
+
+PeerSession::~PeerSession()
+{
+	disconnect();
+}
+
 bool PeerSession::interpret(RLP const& _r)
 {
 	switch (_r[0].toInt<unsigned>())
@@ -39,22 +48,34 @@ bool PeerSession::interpret(RLP const& _r)
 		}
 		cout << std::setw(2) << m_socket.native_handle() << " | Client version: " << m_clientVersion << endl;
 		break;
+	case Disconnect:
+		m_socket.close();
+		return false;
+	case Ping:
+	{
+		RLPStream s;
+		sealAndSend(prep(s).appendList(1) << Pong);
+		break;
+	}
+	case Pong:
+		cout << "Latency: " << chrono::duration_cast<chrono::milliseconds>(std::chrono::steady_clock::now() - m_ping).count() << " ms" << endl;
+		break;
+	default:
+		break;
 	}
 	return true;
 }
 
-PeerSession::PeerSession(bi::tcp::socket _socket, uint _rNId): m_socket(std::move(_socket)), m_reqNetworkId(_rNId)
+void PeerSession::ping()
 {
+	RLPStream s;
+	sealAndSend(prep(s).appendList(1) << Ping);
+	m_ping = std::chrono::steady_clock::now();
 }
 
-PeerSession::~PeerSession()
-{
-	disconnect();
-}
-
-void PeerSession::prep(RLPStream& _s)
+RLPStream& PeerSession::prep(RLPStream& _s)
 {
-	_s.appendRaw(bytes(8, 0));
+	return _s.appendRaw(bytes(8, 0));
 }
 
 void PeerSession::sealAndSend(RLPStream& _s)
@@ -89,6 +110,7 @@ void PeerSession::disconnect()
 	s.appendList(1) << Disconnect;
 	sealAndSend(s);
 	sleep(1);
+	m_socket.close();
 }
 
 void PeerSession::start()
@@ -108,7 +130,6 @@ void PeerSession::doRead()
 	{
 		if (!ec)
 		{
-			std::cout << "Got data" << std::endl;
 			m_incoming.resize(m_incoming.size() + length);
 			memcpy(m_incoming.data() + m_incoming.size() - length, m_data.data(), length);
 			while (m_incoming.size() > 8)
@@ -128,7 +149,6 @@ void PeerSession::doRead()
 					break;
 			}
 		}
-		//doWrite(length);
 		doRead();
 	});
 }
@@ -185,6 +205,19 @@ bool PeerServer::connect(string const& _addr, uint _port)
 	}
 }
 
+void PeerServer::process()
+{
+	m_ioService.poll();
+	// TODO: Gather all transactions, blocks & peers.
+}
+
+void PeerServer::pingAll()
+{
+	for (auto& i: m_peers)
+		if (auto j = i.lock())
+			j->ping();
+}
+
 void PeerServer::sync(BlockChain& _bc, TransactionQueue const& _tq)
 {
 /*
diff --git a/libethereum/PeerNetwork.h b/libethereum/PeerNetwork.h
index 083277695..3057cfd90 100644
--- a/libethereum/PeerNetwork.h
+++ b/libethereum/PeerNetwork.h
@@ -57,40 +57,48 @@ public:
 	~PeerSession();
 
 	void start();
-
-	bool interpret(RLP const& _r);
-
 	void disconnect();
 
+	void ping();
+
 private:
 	void doRead();
 	void doWrite(std::size_t length);
+	bool interpret(RLP const& _r);
 
-	void prep(RLPStream& _s);
+	RLPStream& prep(RLPStream& _s);
 	void sealAndSend(RLPStream& _s);
 	void send(bytes& _msg);
 
 	bi::tcp::socket m_socket;
-	std::array<byte, 1024> m_data;
+	std::array<byte, 65536> m_data;
 
 	bytes m_incoming;
 	std::string m_clientVersion;
 	uint m_protocolVersion;
 	uint m_networkId;
 	uint m_reqNetworkId;
+
+	std::vector<bytes> m_incomingTransactions;
+	std::vector<bytes> m_incomingBlocks;
+	std::vector<bi::tcp::endpoint> m_incomingPeers;
+
+	std::chrono::steady_clock::time_point m_ping;
 };
 
 class PeerServer
 {
 public:
+	/// Start server, listening for connections on the given port.
 	PeerServer(uint _networkId, short _port);
+	/// Start server, but don't listen.
 	PeerServer(uint _networkId);
 
 	/// Conduct I/O, polling, syncing, whatever.
 	/// Ideally all time-consuming I/O is done in a background thread, but you get this call every 100ms or so anyway.
-	void run() { m_ioService.run(); }
-	void process() { m_ioService.poll(); }
+	void process();
 
+	/// Connect to a peer explicitly.
 	bool connect(std::string const& _addr = "127.0.0.1", uint _port = 30303);
 
 	/// Sync with the BlockChain. It might contain one of our mined blocks, we might have new candidates from the network.
@@ -102,6 +110,8 @@ public:
 	/// Remove incoming transaction from the queue. Make sure you've finished with the data from any previous incomingTransaction() calls.
 	void popIncomingTransaction() {}
 
+	void pingAll();
+
 private:
 	void doAccept();
 
diff --git a/test/peer.cpp b/test/peer.cpp
index 6a32c00e3..64998fd50 100644
--- a/test/peer.cpp
+++ b/test/peer.cpp
@@ -49,10 +49,12 @@ int peerTest(int argc, char** argv)
 	if (!remoteHost.empty())
 		pn.connect(remoteHost, remotePort);
 
-	while (true)
+	for (int i = 0; ; ++i)
 	{
 		usleep(100000);
 		pn.process();
+		if (!(i % 10))
+			pn.pingAll();
 	}
 
 	return 0;