Cisco-CP7940G recommanded config

[sebviel]

Hi,

I switched to FPL somme months ago, work well for the first weeks inbound & outbound call but not I can't receive any call. Registering is OK, calling out working well too and FPL apps working well to receive call but not my phone.

I tried a lot of configurations but still not able to receive calls. I would like to know if FPL would recommended standard settings for Cisco IP Phones.

Regards,

Seb

[bridonca]

It appears that the Cisco CP7940G needs RTP ports 16384 to 16482 open if they are the default ports. Get the router to forward those ports to the Cisco CP7940G. Save the new settings, power does the modem, router and Cisco CP7940G, for 30 seconds, and see what happens.

[sebviel]

Hi,

My own 2 cents, with the Linksys/Cisco E2500 router, no need to open specific ports, just be sure to do those 2 things:

- Activate SIP ALG in the router
- DO NOT activate the nat_received_processing in your CNF file

FYI from Cisco's :

(Optional) Enables NAT received processing.
Valid values are 0 (disable) and 1 (enable). Default is 0.
If nat_received_processing is enabled, and the received= tag is in
the Via header of the 200 OK response from a REGISTER, the IP
address in the received= tag is used instead of the nat_address in the
Contact header. If this switch occurs, the phone unregisters the old
IP address and reregisters with the new IP address.


Enjoy your free calls !!

Seb

[bridonca]

Most people have problems with SIP ALG enabled, because most implementations of SIP ALG are broken. But if it works for you, power to you. As long as you use whatever solution that allows specific RTP ports to the ATA device, you no longer have the one way audio issue.