Problem with a remote extension (SIP timeout?)

Hi Guys,

I have an asterisk 1.6 running behind a NAT with a couple of local extensions and one thats outside the nat but behind another nat/router elsewhere.

I can call that extension right after it registers just fine. But after a few minutes, I can no longer initiate a call. It says auto-congesting and doesn’t even ring the remote extension.

If the remote extension (ATA a LinkSYS PAP2T-NA) is reset, it re-registers and becomes “callable” again. So it sounds like some kind of timeout but I can’t figure out why.

My nat / firewall rules are all okay, I guess, since I can make a call to that extension when its reset.

Also, no matter how long it has been after the “register”, the remote extension can make calls just fine, so I think we can safely rule-out firewall rules.

It sounds like some kind of a timeout but AFAIK SIP control stuff is UDP, so there isn’t a chance of timeout, right ?

Oh and yea, the remote extension keeps showing up in the “registered” list on the server, when I do " sip show peers"

Any help would be a life-saver… PLEASE !!!

Thank you all,

---- Here is my config ----


Please note that the last two lines were added for experimentation.

qualify=yes or with a specific number of ms e.g. qualify=9000 - results in immediate error from my asterisk saying “remoteuser1 is unreachable”

nat=yes / nat=1 doesn’t seem to effect anything

I am guessing, its an issue with the PAP2 on the remote-end but no idea how to fix it.

Thanks again guys!