On November 24, 2021, Microsoft announced changes to their Direct Routing SIP interface and Teams Direct Routing. Below is a summary of those announcements.

Direct Routing will stop processing SIP requests which have ‘Replaces’ headers

Change:  Starting on January 3rd, 2022, Direct Routing will stop processing SIP requests which have ‘Replaces’ headers. This will affect organizations as Direct Routing will reject SIP requests that have ‘Replaces’ headers defined. An organization that thinks they may be affected by this will have to consult with their Session Border Controller to be sure that they are not using ‘Replaces’ headers in SIP requests.

Impact on your Organization: When this change is implemented, Direct Routing will reject SIP requests that have Replaces headers defined.

For Altigen customers and partners – None; Altigen customers and partners will not be impacted by this change.

Trusted certificate authorities for Direct Routing SIP interface

Change:  Starting on February 1, 2022, the Direct Routing SIP interface will only trust certificates that are signed by Certificate Authorities (CAs) that are part of the Microsoft Trusted Root Certificate Program.  If your SBC certificate is not signed by a CA, your service may be impacted when this change takes effect. Unsupported certificates will not be accepted and you will lose PSTN connectivity via Direct Routing.

Impact on your Organization: If your SBC certificate is not signed by a CA, your service may be impacted when this change takes effect. Unsupported certificates will not be accepted and you will lose PSTN connectivity via Direct Routing.

For Altigen customers and partners – None; Altigen services and solutions are signed by CA’s. Therefore, Altigen customers and partners will not be impacted by this change.

If your current service provider is affected, feel free to get in touch with us to see how we can help your organization be ready for the changes. Click here.