[Freeswitch-users] Forcing CN offer

[Anthony Minessale]

if you set the var verbose_sdp=true globally in vars.xml or on a
per_leg basis you will get the extra a= that some things mistakenly
think are mandatory (like some older polycom firmwares) the goal is to
make the sdp as small as possible to prevent going over the MTU

On Thu, Aug 25, 2011 at 4:25 AM, Alex Massover <alex at jajah.com> wrote:
> Hello,
>
>
>
> I’m working on the following scenarios:
>
> scenario 1:  A  à FS à B
>
> scenario 2: C à FS à A
>
>
>
> Where A supports CN (a=rtpmap:13 CN/8000) and requires CN negotiation, and B
> and C do not support and aren’t able to negotiate it.
>
>
>
> I successfully implemented scenario 1, CN is negotiated between A party and
> FS, and not negotiated between FS and B.
>
>
>
> But scenario 2 doesn’t work for me! When C doesn’t offer CN in INVITE
> towards FS, FS also doesn’t offer CN in SDP in INVITE towards A.
>
> And nothing helps, tried all the combination of VAD options. Gateway A is in
> the same internal sip profile in both scenarios.
>
>
>
> This is the SDP in INVITE from C to FS:
>
>
>
>             Media Description, name and address (m): audio 30224 RTP/AVP 0 8
> 18 101
>
>             Media Attribute (a): rtpmap:0 PCMU/8000
>
>             Media Attribute (a): rtpmap:8 PCMA/8000
>
>             Media Attribute (a): rtpmap:18 G729/8000
>
>             Media Attribute (a): fmtp:18 annexb=no
>
>             Media Attribute (a): rtpmap:101 telephone-event/8000
>
>             Media Attribute (a): fmtp:101 0-16
>
>             Media Attribute (a): silenceSupp:off - - - -
>
>             Media Attribute (a): ptime:20
>
>             Media Attribute (a): sendrecv
>
>
>
>
>
> And this is the SDP from FS towards A:
>
>             Media Description, name and address (m): audio 23564 RTP/AVP 0 8
> 101 13
>
>             Media Attribute (a): rtpmap:101 telephone-event/8000
>
>             Media Attribute (a): fmtp:101 0-16
>
>             Media Attribute (a): ptime:20
>
>
>
> FS even puts 13 in m= attribute, but doesn’t add a=  attribute for
> rtpmap:13.
>
>
>
>
>
> Is that a bug?
>
>
>
>
>
> --
>
> Best Regards
>
> Alex Massover.
>
> This mail was sent via Mail-SeCure System.
>
>
> FreeSWITCH-users mailing list
> FreeSWITCH-users at lists.freeswitch.org
> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
> UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
> http://www.freeswitch.org
>
>



-- 
Anthony Minessale II

FreeSWITCH http://www.freeswitch.org/
ClueCon http://www.cluecon.com/
Twitter: http://twitter.com/FreeSWITCH_wire

AIM: anthm
MSN:anthony_minessale at hotmail.com
GTALK/JABBER/PAYPAL:anthony.minessale at gmail.com
IRC: irc.freenode.net #freeswitch

FreeSWITCH Developer Conference
sip:888 at conference.freeswitch.org
googletalk:conf+888 at conference.freeswitch.org
pstn:+19193869900