[Asterisk-Users] SIP Phones behind dynamic IPs

[Gareth Blades]

I would also recomend that you upgrade to the latest firmware 1.0.2.13
(contact grandstream) as it does fix some registeration issues and have
extra NAT/STUN features.

On Wed, 2006-05-03 at 17:15, Chris Bagnall wrote:
> Greetings list,
> 
> I'm coming across an issue with some of the GXP-2000 phones we have out in
> the wild at clients' employees' homes. In most cases they're behind consumer
> ADSL NAT routers on a dynamic IP from their ISP.
> 
> In a nutshell, the phone is unable to be called unless it's restarted first,
> after which it's fine for a good few hours, then it stops working until
> restarted again.
> 
> The problem doesn't seem to be anywhere near as regular with users that are
> on cable connections (these tend to have much more "sticky" IP addresses -
> they change only every few months rather than every time the ADSL router
> connects), and non-existent on ADSL connections with static IPs.
> 
> I've tried various permutations - with STUN, without STUN, NAT keep-alives
> down as low as 10 seconds, nat=yes in sip.conf, ports forwarded to the
> phone, ports *not* forwarded to the phone, etc.
> 
> I think what's happening is that the ADSL router is reconnecting after a
> break in the connection (as it should), getting a different IP, but the
> phones don't seem to be recognising they've got a different IP and updating
> the asterisk server with the good news.
> 
> Has anyone else encountered similar issues? Anything else I can try (bearing
> in mind I have no control over the ADSL connections the users are subscribed
> to)?
> 
> Thanks in advance.
> 
> Regards,
> 
> Chris