Forum Discussion
Microsoft Teams Direct Routing - Call forwarding isn't working
I will review your answers and let you know when the issue is solved.
DominikA9522 did you figure out the root cause? If so can you please share some insights.
Hello MangnusPrem
This issue is still under investigation by MSFT and our SBC Vendor.
I'll share the results whenever we got a solution.
Hello,
meanwhile this issue was located between Microsoft and Atos/Unify as SBC manufacturer:
The SBC id disabling the video channel by setting a port of 0.
Then it is also providing a RTCP port on a disabled channel.69577 00068222 2023-06-30 09:01:05.822 24064 MEDIAMGR_CORE TL_INFO CSDPParser::LogSdp() [00000000]: [sdp][remote] m=video 0 RTP/SAVP 122 125 107 99 123
69578 00068223 2023-06-30 09:01:05.822 24064 MEDIAMGR_CORE TL_INFO CSDPParser::LogSdp() [00000000]: [sdp][remote] c=IN IP4 10.*4.*08.*1
69579 00068224 2023-06-30 09:01:05.822 24064 MEDIAMGR_CORE TL_INFO CSDPParser::LogSdp() [00000000]: [sdp][remote] a=rtcp:1
69582 00068227 2023-06-30 09:01:05.822 24064 MEDIAMGR_CORE TL_INFO CSDPParser::LogSdp() [00000000]: [sdp][remote] a=rtcp-mux
69583 00068228 2023-06-30 09:01:05.822 24064 MEDIAMGR_CORE TL_INFO CSDPParser::LogSdp() [00000000]: [sdp][remote] a=candidate:2146435078 1 UDP 2122317696 81.*96.*71.*66 0 typ host
69584 00068229 2023-06-30 09:01:05.822 24064 MEDIAMGR_CORE TL_INFO CSDPParser::LogSdp() [00000000]: [sdp][remote] a=sendonly
69585 00068230 2023-06-30 09:01:05.823 24064 MEDIAMGR_CORE TL_ERROR CSDPParser::Parse_ma() [AA431FDA70]: invalid rtcp port 1 (../src/mediamgr/src/SDPParser.cpp:2912)
69586 00068231 2023-06-30 09:01:05.823 24064 MEDIAMGR_CORE TL_ERROR CSDPParser::Parse() [AA431FDA70]: parse sdp error (../src/mediamgr/src/SDPParser.cpp:1718)
69588 00068233 2023-06-30 09:01:05.823 24064 MEDIAMGR_CORE TL_ERROR GetSessionFromSdp() [00000000]: Failed to parse sdp 0x80ee0007 (../src/mediamgr/src/SDPParser.cpp:9734)
This failure is causing the client to fail and what is killing the call.
Vs the working call
Everything is the same, except a rtcp port 1 of is not being provided.
If the customer updates the SBC so it is not doing this, it should resolve the issue.36223 00035693 2023-06-30 09:04:06.006 18524 MEDIAMGR_CORE TL_INFO CSDPParser::LogSdp() [00000000]: [sdp][remote] m=video 0 RTP/SAVP 122 125 107 99 123
36224 00035694 2023-06-30 09:04:06.006 18524 MEDIAMGR_CORE TL_INFO CSDPParser::LogSdp() [00000000]: [sdp][remote] c=IN IP4 192.*68.*01.*26
36227 00035697 2023-06-30 09:04:06.006 18524 MEDIAMGR_CORE TL_INFO CSDPParser::LogSdp() [00000000]: [sdp][remote] a=rtcp-mux
36228 00035698 2023-06-30 09:04:06.006 18524 MEDIAMGR_CORE TL_INFO CSDPParser::LogSdp() [00000000]: [sdp][remote] a=candidate:2146435078 1 UDP 2122317696 212.*85.*8.*45 0 typ host generation 0
36229 00035699 2023-06-30 09:04:06.006 18524 MEDIAMGR_CORE TL_INFO CSDPParser::LogSdp() [00000000]: [sdp][remote] a=sendonly##########################
The external Call Forwarding by name includes Video codecs which are not included by calling with number.
In general MS describes thats DirectRouting calls does not include Video codecs
https://answers.microsoft.com/en-us/msteams/forum/all/teams-direct-routing-video-support/ce7a9878-6a8f-4525-b0bc-0261e0350a7c & https://learn.microsoft.com/en-us/microsoftteams/direct-routing-plan#media-traffic-port-ranges
But in this special case they send Video request. The C-Party does not support Video and the SBC disabled this Media stream for video with answering those m-lines which are requested , so also the video line, where the port is set to 0
The MS Client could not parse this and rejects the call.
The SBC manufacturer implements now a workaround with deletes the rtcp port:0
But also MS has to check in their view that now Video is requested in the Invite by external call forwarding.
For us this point is closed and the call forwarding is working.