[asterisk-users] GXP2000, Linksys RV082 Firewall / NAT, Registrations

[lists at infoway.net]

Hello,

We have several clients with GXP2000 in their network and behind NAT. We
have one particular client that has several GXP2000 behind a Linksys RV082
VPN Firewall/Router which is doing NAT services. According to SIP packet
inspection, it detects it's a symmetric NAT.

The problem we have is that even though we have configured Asterisk AND
the GXP2000 to register every 60 minutes, they keep unregistering and
re-registering every few couple of minutes (between 4 and 10 minutes).

We have checked the client's Internet connection and it's not bouncing as
well as their local network is working stable.

So, the only thing we can think of why these phones are re-registering so
often is their firewall device since it's the only "difference" between
this client and our other clients that use the GXP2000.

Does anyone have any idea why this is happening or how this can be resolved?

Thanks,
Daniel