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

Michael Maier m1278468 at mailbox.org
Thu Jan 24 12:07:50 CST 2019

On 24.01.19 at 14:31 Joshua C. Colp wrote:
> 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


More information about the asterisk-dev mailing list