[asterisk-users] No compatible codecs, not accepting this offer!

[James Sharp]

On 1/15/2014 3:59 AM, Francesco Namuri wrote:
> Hello,
> I'm having this issue on my pbx, it appears that asterisk is refusing
> the codecs that my providers is proposing.
> My trunk configuration is:
>

Pretty simple -


> ---
> username=5x5x7x9x0x3
> type=friend
> secret=CRcxn7sqwm
> qualify=yes
> port=5060
> insecure=port,invite
> host=sip.txtxlxoxp.it
> fromuser=5x5x7x9x0x3
> fromdomain=sip.txtxlxoxp.it
> disallow=all
> context=from-trunk
> allow=alaw

Here you're disallowing all codecs except alaw.

> ---
>
> A typical invite from my provider is:
>
> <--- SIP read from UDP:xx.yy.xx.yy:5060 ---> INVITE sip:5x5x7x9x0x3 at 192.168.1.168:5060 SIP/2.0
> Via: SIP/2.0/UDP xx.yy.xx.yy:5060;branch=z9hG4bKt5sfh7nrvok3d5gqc3ritdv7b7
> From: <sip:3x8x6x3x3x at 10.39.1.19;user=phone>;tag=SDdgce901-90915
> To: "SIPLineUser SIPLineUser"<sip:5x5x7x9x0x3 at sip.txtxlxoxp.it>
> Call-ID: SDdgce901-9cb68ba025684f03a4094ed71e6e04f8-ao92gd1
> CSeq: 59458 INVITE
> Content-Type: application/sdp
> Contact: <sip:3x8x6x3x3x at xx.yy.xx.yy:5060;user=phone;transport=udp>
> User-Agent: Nortel SESM 14.1.0.12
> Max-Forwards: 19
> Supported: com.nortelnetworks.firewall,p-3rdpartycontrol,nosec,join,x-nortel-sipvc,gin,com.nortelnetworks.im.encryption,replaces,100rel
> Remote-Party-ID: <sip:3x8x6x3x3x at sip.txtxlxoxp.it;user=phone>;screen=yes;screen-ind=0;party=calling;counter=0;npi=NPI_E164;ton=TON_NATIONAL
> P-Asserted-Identity: <sip:3x8x6x3x3x at 10.39.1.19;user=phone>
> Allow: UPDATE,REFER
> Content-Length: 293
>
> v=0
> o=- 0 138163748 IN IP4 xx.yy.xx.yy
> s=IMSS
> e=unknown at invalid.net
> c=IN IP4 xx.yy.xx.yy
> t=0 0
> m=audio 43718 RTP/AVP 8 18 3 101
> a=fmtp:18 annexb=no
> a=rtpmap:18 G729/8000
> a=rtpmap:3 GSM/8000/1

But....provider will only send GSM or G729.

So either you need to talk your provider into sending alaw or you need 
change your allow line to "allow=alaw,gsm".