"A keep-alive is a small piece of data transmitted between a
client and a server to ensure that the connection is still open or
to keep the connection open. Many protocols implement this as a way
of cleaning up dead connections to the server. If a client does not
respond, the connection is closed.
"SSH does not enable this by default. There are pros and cons to
this. A major pro is that under a lot of conditions if you
disconnect from the Internet, your connection will be usable when
you reconnect. For those who drop out of WiFi a lot, this is a
major plus when you discover you don't need to login again.
"For those who get the following message from their SSH client
when they stop typing for a few minutes it's not as
convenient:"
