Over the past few weeks I have setup Microsoft Teams Direct Routing on Ribbon SBCs in a number of countries all over the world. On a few occasions I have run into a“484 Address Incomplete” issue when making outbound calls from Microsoft Teams.

It would appear that some carriers don’t like the P-Asserted-Identity that is applied when the call leaves Microsoft. The solution is to strip the P-Asserted-Identity SIP header just before it leaves the SBC as it heads towards the carrier.

Example of the SIP 484 error:

Received From On via UDPCALL-ID: call-1BE92823-0000-0010-021E-104B@ …

Matt Ellis

Unified Communications Architect, Pompey fan, burger eater, coffee drinker...

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