View Single Post
Unread 10-11-2007, 09:30 PM   #1
Senior Member
Join Date: Jul 2007
Posts: 143
Thanks: 13
Thanked 20 Times in 19 Posts
green will become famous soon enough
Default PSTN gateway codec order

Currently when I dial PSTN access number Sipbroker gateway will setup a call with the following codec order:

RTP/AVP 0 18 8 111 97 3 4 101

a=rtpmap:0 PCMU/8000
a=rtpmap:18 G729/8000
a=fmtp:18 annexb=no
a=rtpmap:8 PCMA/8000
a=rtpmap:111 G726-32/8000
a=rtpmap:97 iLBC/8000
a=rtpmap:3 GSM/8000
a=rtpmap:4 G723/8000
It will be more logical to make it looking like 0 8 18 111 97 3 4 101,
i.e. puth both PCM codecs first and lower bandwidth codecs after.

This is my real problem. I'm dialing my home VSP using the SIP-code. The SIP account with my home VSP is forwarded permanently to the local PSTN number. As soon as PCMU is not supported by my VSP the call is established with G.729 (according to Sipbroker's preference) while I need G.711A!

green is offline   Reply With Quote