[Asterisk-Users] Polycom behind firewall issue

[Chris Mason (Lists)]

I have a user that just got a broadband connection so she could have an 
extension off our pbx. The service is DSL and uses a speedstream 5200 
dsl router. I sent her a Polycom IP300. At first it would not access the 
config files via ftp so I had tech support walk her through setting the 
phone's internal IP to be the dmz. This allowed me to set up the phone 
using the web interface and now it registers. We had NAT problems so I 
set the NAT features of the phone:
IP Address: 67.136.nnn.nnn
Signalling Port : 5060
Media Port Start: 10000

In sip.conf, I have
nat=yes
externalip=67.136.nnn.nnn
qualify=yes

I can call the user and she can hear me. If she calls me, no voice can 
be heard either way. When I run sip show channels, I see:

Peer             User/ANR    Call ID      Seq (Tx/Rx)   Format  Last Msg
192.168.0.169    805         02fe2b2a684  00102/00000   g729    Tx: ACK
67.136.nnn.nnn    893         8dae34ea-ae  00101/00001   g729    Rx: INVITE
67.136.nnn.nnn    (None)      3926de51-a1  00101/00001   unknow  Rx: 
REGISTER


and it just stays like that until the call is terminated. I would think 
it was an rtp / nat problem, any ideas how to fix?

-- 
Chris Mason
NetConcepts
(264) 497-5670 Fax: (264) 497-8463
Int:  (305) 704-7249 Fax: (815)301-9759 
Cell: 264-235-5670
Yahoo IM: netconcepts_anguilla at yahoo.com