[asterisk-dev] 13.24.1 / PJSIP: early media via 180 Ringing containing SDP is ignored

[Joshua C. Colp]

On Thu, Jan 24, 2019, at 9:23 AM, Michael Maier wrote:
> On 24.01.19 at 12:08 Joshua C. Colp wrote:
> > On Thu, Jan 24, 2019, at 7:00 AM, Michael Maier wrote:
> >> Hello!
> >>
> >> Given is an outbound call to a callee via asterisk to the ISP. After 
> >> INVITE, the ISP sends 100 Trying and some time later 180 Ringing *w/* 
> >> SDP and the header
> >> "P-Early-Media: sendonly" (no 183 or any other thing until callee 
> >> responds). SDP in 180 contains media attribute *sendrecv* 
> >> (contradicting to the P-Early-Media header).
> >>
> >> Asterisk 13.24.1 sends PRACK to the ISP (w/o SDP) and the 180 to the 
> >> caller - but SDP is dropped and therefor no early media is possible!
> >>
> >> Is this behavior a bug or a feature?
> > 
> > It would be a bug. That's not a scenario that I think anyone has really tested or fully scoped out. Is media actually received while in the 180 with Ringing stage?
> 
> Yes - there is actually media been sent by the ISP, which is completely 
> ignored by asterisk:
> 
> [2019-01-24 13:24:20] DEBUG[3341][C-00000026]: res_rtp_asterisk.c:4109 
> ast_rtp_write: No remote address on RTP instance '0x7fedc40586d8' so 
> dropping frame
> 
> At this point, there isn't any media flowing between caller and 
> asterisk and from asterisk to callee - just the ISP sends media to 
> asterisk.
> 
> Media is sent to the caller by asterisk at the moment, the 200 OK w/ 
> SDP package has been received after callee picked up the phone. 
> Therefore, the first few syllables are
> lost and you have to ask the name of the callee again, e.g.

I'd suggest filing an issue[1] with a trace and console output then.

[1] https://issues.asterisk.org/jira

-- 
Joshua C. Colp
Digium - A Sangoma Company | Senior Software Developer
445 Jan Davis Drive NW - Huntsville, AL 35806 - US
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