[SR-Users] rtpengine via-branch=extra question

[Juha Heinanen]

Juha Heinanen writes:

>   via-branch=... - Include the “branch” value of one of the “Via” headers
>   in the request to the RTP proxy. Possible values are: “1” - use the
>   first “Via” header; “2” - use the second “Via” header; “auto” - use the
>   first “Via” header if this is a request, or the second one if this is a
>   reply; “extra” - don't take the value from a header, but instead use the
>   value of the “extra_id_pv” variable. This can be used to create one
>   media session per branch on the RTP proxy. When sending a subsequent
>   “delete” command to the RTP proxy, you can then stop just the session
>   for a specific branch when passing the flag '1' or '2' in the
>   “rtpengine_delete”, or stop all sessions for a call when not passing one
>   of those two flags there.
> 
> if via-branch=extra is used in offers of branched, should it also be
> used in answers and deletes?

i made some experiments on this.  i used "extra" in both offer and
answer.  when i delete a branch of a two branch call using "extra", i
get to syslog:

Nov 19 04:39:53 lohi /usr/bin/sip-proxy[17427]: INFO: ===== rtpengine_delete(via-branch=extra) branch <z9hG4bK8c24c4009181072c1>
Nov 19 04:39:53 lohi rtpengine[13555]: [aced513d17fc9ff5] Received command 'delete' from 192.98.102.10:41009
Nov 19 04:39:53 lohi rtpengine[13555]: [aced513d17fc9ff5] Dump for 'delete' from 192.98.102.10:41009: { "call-id": "aced513d17fc9ff5", "via-branch": "z9hG4bK8c24c4009181072c1", "received-from": [ "IP4", "192.98.102.10" ], "from-tag": "be4468b7fa8902f6", "command": "delete" }
Nov 19 04:39:53 lohi rtpengine[13555]: [aced513d17fc9ff5] Scheduling deletion of call branch 'be4468b7fa8902f6' in 30 seconds

why is it telling that the branch to be deleted is that of the from tag,
i.e., the whole call?

i then made another test, using "1" in delete and got:

Nov 19 04:42:18 lohi /usr/bin/sip-proxy[30711]: INFO: ===== rtpengine_delete(via-branch=1) branch <z9hG4bKa0c011f1e570422e1>
Nov 19 04:42:18 lohi rtpengine[13555]: [4b4b6950709a0353] Received command 'delete' from 192.98.102.10:59697
Nov 19 04:42:18 lohi rtpengine[13555]: [4b4b6950709a0353] Dump for 'delete' from 192.98.102.10:59697: { "call-id": "4b4b6950709a0353", "via-branch": "z9hG4bKa0c011f1e570422e", "received-from": [ "IP4", "192.98.102.10" ], "from-tag": "70283a0a11af785c", "command": "delete" }
Nov 19 04:42:18 lohi rtpengine[13555]: [4b4b6950709a0353] Scheduling deletion of call branch '70283a0a11af785c' in 30 seconds

again the same thing, i.e., from tag branch is to be deleted.

after answering, i kept the call up for a couple of minutes and in both
cases the whole call was not deleted.

also, in either case i didn't get any notice to syslog when the
scheduled deletion of the call branch actually happened.

what is the proper via-branch value in rtpengine_delete?  based on
above, it does not seem to matter if i use "extra" or "1".

also, does rtpengine_delete need to be called at all on a failed branch,
i.e., would the offer timeout anyhow, since matching answer never game?

-- juha