Added doc comment
diff --git a/ndn-cpp/transport/TcpTransport.hpp b/ndn-cpp/transport/TcpTransport.hpp
index 8be6a73..8b714e8 100644
--- a/ndn-cpp/transport/TcpTransport.hpp
+++ b/ndn-cpp/transport/TcpTransport.hpp
@@ -20,6 +20,10 @@
     ndn_ = 0;
   }
   
+  /**
+   * 
+   * @param ndn Not a shared_ptr because we assume that it will remain valid during the life of this Transport object.
+   */
   virtual void connect(NDN &ndn);
   
   virtual void send(unsigned char *data, unsigned int dataLength);