Fix to make the TCP SYN retransmission do a binary exponential backoff

src/internet-node/tcp-socket.cc

@@ -471,6 +471,7 @@ void TcpSocket::SendEmptyPacket (uint8_t flags)
   if (flags & TcpHeader::SYN)
     {
       rto = m_cnTimeout;
+      m_cnTimeout = m_cnTimeout + m_cnTimeout;
       m_cnCount--;
     }
   if (m_retxEvent.IsExpired () ) //no outstanding timer

src/node/tcp.cc

@@ -54,12 +54,12 @@ NumericDefaultValue<uint32_t>       Tcp::defaultInitialCWnd
 NumericDefaultValue<uint32_t>       Tcp::defaultConnTimeout
 ("TcpDefaultConnTimeout",
 "Default TCP retransmission timeout when opening connection (seconds)",
-6);
+3);
 
 NumericDefaultValue<uint32_t>       Tcp::defaultConnCount
 ("TcpDefaultConnCount",
 "Default number of connection attempts (SYN retransmissions) before returning failure",
-3);
+6);
 
 NS_OBJECT_ENSURE_REGISTERED (Tcp);