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http://www.no-ip.com/downloads.php?page=win

I use it for the same purposes. Just add the client to any machine behind your public address (if nat'ng) and any changes to the IP address will...

I had a similar problem...
Check your logs /var/log/secure and messages, this will at least let you know if the attempted connections arrived or not. If so you will probably see a similar message to...

From the sounds of it you are in a lab environment...
You can easily see if anyone is connected via telnet by the 'who' command:

router#who
or
router#show user

This will show all of the...