NetTcpBinding中的双工通道状态会相应地自动转换为客户端的状态吗？

Question

On client side, I handle the proxy state so that when its State==CommunicationState.Faulted, it will automatically call Abort() and gracefully transition to CommunicationState.Closed. On server side, I have 2 events hooked up to callback channel

OperationContext.Current.Channel.Faulted += Channel_Faulted; OperationContext.Current.Channel.Closed += Channel_Closed;

Here are my events code

private void Channel_Closed(object sender, EventArgs e)
{
    var callback = sender as IPtiCommunicationCallback;
    PtiClient client;
    lock (syncObj)
    {
        client = clientsList.FirstOrDefault(x => x.Value == callback).Key;
    }
    if (client != null)
    {
        //Code to remove client from the list
        Disconnect(client);
    }
}

private void Channel_Faulted(object sender, EventArgs e)
{
    (sender as ICommunicationObject).Abort();
}

Now the question: Will the duplex channel's (the callback channel) state automatically transition accordingly to client's or I have to handle the Faulted State as I did? I'm using NetTcpBinding by the way.

Answer 1

The Callback channel's state will generally mimic the client's state, but this is not guaranteed . For example, if the client is trying to reach the server to close the connection, its state might be Closing while the state on the server side could be Opened . You are handling it correctly in assuming that each side must handle Closed and Faulted states individually.

Answer 2

I have done bit research about what kind of binding should we use and finally decided to go ahead with nettcp binding. See my blog for detail explanation.

http://maheshde.blogspot.com.au/2013/06/duplex-communication-over-internet.html

I have no idea why those events not fired. But triggering WCF call from client every 10 minutes our problem solved.