Commented Issue: IsConnected returns true when sshd has closed connection or network is not available [1898]

Currently, The IsConnection property (on BaseClient) returns true even when:
*** the server has shut down the ssh connection

To reproduce:

1. Create a connection (eg using SftpClient)
2. Kill sshd process on server.
3. Inspect value of IsConnected property.

*** the network is no longer available

To reproduce:

1. Create a connection (eg using SftpClient)
2. Unplug network cable
3. Inspect value of IsConnected property.

I can reproduce this with ssh.net built from SVN/TFS.
Comments: ** Comment from web user: tudisco **

According to:
http://stackoverflow.com/questions/515458/how-can-i-check-whether-a-tcp-socket-is-disconnected-in-c

There is a way to tell. But I have no experience with this problem.

I keep getting the same exception as https://sshnet.codeplex.com/workitem/1581