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Microsoft Teams | Microsoft Teams for business | Meetings and calls | Audio and video
Managing sound and video settings during Teams meetings and calls for optimal communication
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Hi Arup,
Thank you for reaching out and for sharing the details of your planned solution, in which PSTN calls are routed through Teams Direct Routing to your Azure-hosted application using Teams Phone Extensibility and ACS Call Automation.
ACS Call Automation does support SIP UUI and X-Headers; however, only headers that follow the supported naming format are passed into the IncomingCall event, which means headers sent with any other name will not appear in the payload.
To ensure the headers reach your application as expected, I recommend the following steps:
1/ Configure the header format on your SBC
- Add the prefix X-MS-Custom- to each custom header name, for example, X-MS-Custom-CaseId.
- Then, keep each header name within 64 characters, including the prefix, and each value within 256 characters.
- Furthermore, please send no more than 5 custom SIP headers per call.
- Finally, place any UUI data in the standard User-to-User header.
- Reference: Microsoft Teams Phone capabilities in Calling and Call Automation SDKs - An Azure Communication Ser…
2/ Retrieve the headers in your Call Automation application
- Once the call arrives, open the custom context section of the IncomingCall event.
- From there, your X-Headers are available under the SIP headers list, while the UUI value is available under the user-to-user field.
- During testing, I also recommend logging the full IncomingCall event so that you can clearly see every value received.
- Reference: Azure Communication Services Call Automation How-to for Passing Call Contextual Data in Call Automa…
3/ Validate the behavior with a test call
- Place a test call from the PSTN to the Teams number assigned to your solution.
- Compare the SIP INVITE leaving your SBC with the IncomingCall event received by your application.
- If a header appears on the SBC but is missing from the event, please share the SBC trace, the call time with time zone, and the Call Automation correlation ID, so that I can investigate this further for you.
I hope this information suits your scenario and helps you move forward with confidence. Should you have any further questions, please feel free to let me know, and I will be glad to assist.
Warm regards,