Hi

I have a Draytek :

Model Name : Vigor2930Vn
Firmware Version : v3.3.0

I am running some IP Phones (Cisco 303) over a fibre connection, running through the Draytek.

The phones are registering ok, but occasionally dropping off when left idle. The supplier says that their switch will try and contact the phone(s) if been idle for a while. If can't get back to the phone, it will unregister itself. Causing the phone or one of the extensions to not work.

This is an intermittent problem and only affect some phones(s) and extension(s) but not always the same phones have the problem. Once the problem occurs rebooting the phone generally doesn't resolve it either. I have to give it dhcp or a different static address for it to work.

When the problem occurs I get ARP Address mismatch on the router logs. Although I can't identify which device this relates to.

All the phones are static ip, not being used by anything else, out of the dhcp range.

Was wondering if I could put the phones on a different ip range, not sure if this would help or not.

I'm not using any VoIP/Sip features on the router as such. Just using the router to enable the phones to get an internet connection.

Any ideas?


Thanks


Jon

Whats the PBX?
Can you set up a ping from it to the handsets?

We don't have access to it.

I've just tried increasing the NAT keep alive interval from 15 secs to 120 on the phone sip options.

Read the default option is overkill and can cause problems.