Sorry to hear you're having to interoperate with Teams. It's a unique form of sadism I wouldn't wish upon anyone.
A few theories:
1) Microsoft doesn't like the "bare" Contact header-value here:
Contact: sip:+MY_FROM_PHONE_NUMBER_HERE@MY_FQDN_WAS_HERE:5061;transport=tls
Unlike the careted one right above:
P-Asserted-Identity: sip:+MY_FROM_PHONE_NUMBER_HERE@MY_FQDN_WAS_HERE
A bare URI absent other header-params is of course completely legal, but I'm really trying to get inside the imaginary world of antisocial "Microsoft SIP" here.
2) Could it be that antisocial "Microsoft SIP" sends 400 as a way of objecting to something in the SDP, e.g. where a non-demented SIP stack would send "488 Not Acceptable Here" or "415 Unsupported Media Type"?
I know you've said you tried multiple clients to rule that out, but I wonder if the thing it's objecting to hasn't been ruled out that way.
3) I saw this media line in the SDP:
m=application 41356 <unknown media type>
What's that?
-- Alex
On Dec 29, 2022, at 9:51 AM, Brandon Armstead brandon@cryy.com wrote:
Outbound calls from my SBC into Teams (Polycom -> SBC -> Teams) always result in a 400 BAD REQUEST. Example invite below: https://pastebin.com/F1G1Ce59 I've taken care to make sure numbers are all E.164 format in From/To/Contact. I've also taken care to make sure that FQDN is used in Contact and Record-Route header. I've tried many different variations and have followed the SIP information here: https://learn.microsoft.com/en-us/microsoftteams/direct-routing-protocols-si... I've also tried several different clients (Bria, Polycom CCX 600, Grandstream, etc) to see if maybe it was something in the SDP or otherwise causing an issue. SIP Transport is TLS, RTP is SRTP I might also add that OPTION pings are active and Direct Routing Endpoint is active, so this is successful. I also am able to receive calls FROM teams to my IP phone(s) without issue. It is only when I try and call INTO teams (INVITE -> Microsoft Teams) that I always receive a 400 BAD REQUEST to my INVITE. Any help is appreciated, thank you!
- Brandon
Kamailio - Users Mailing List - Non Commercial Discussions To unsubscribe send an email to sr-users-leave@lists.kamailio.org Important: keep the mailing list in the recipients, do not reply only to the sender! Edit mailing list options or unsubscribe: