Ping is a good start...

[JeffVandervoort]

...but not enough.

I'd like to configure PCM to attempt a TCP or UDP connection to specific port(s) on remote computer(s) to verify that they're listening. For example, verify that TCP 3389 is listening on a Remote Desktop Session Host, or UDP 53 on a DNS server.

You don't have to have much running for a PING test to pass, so it's a pretty minimal test. But in addition, Ping is often exempted from IPSec. So by checking for other protocols that aren't exempted from IPSec, you can also get an idea if IPSec is your connectivity problem.

[JeffVandervoort]

Oops...never mind. I can already monitor ports on a remote computer. Just didn't notice it in the GUI!

[Marius]