Guides & References
If you're new to RFCs and wanting to dig into the finer details of SIP (or any protocol) check out the "how to read an RFC" blog post — well worth a look. For a more casual explore of the RFCs available checkout rfc.fyi (you'll see that searching SIP gives plenty of results!).
Teams Direct Routing Setup
Configure Microsoft 365 and Teams voice routing so VoIP Toolbox can test users, auto attendants, and call queues.
Teams Setup
Connect your Microsoft 365 tenant once, then set up call records and Direct Routing from a single page.
SIP Core RFCs
Core SIP protocol RFCs including 3261, 3262–3264, and related specs.
SIP Extension RFCs
P-Asserted-Identity, REFER, Replaces, Reason, Session-Expires, SRTP, and more.
Q.850 Code Table
ITU Q.850 cause codes used in SIP Reason headers (RFC 6432).
Compact Header Table
SIP compact header single-letter abbreviations (RFC 3261).