https://learn.microsoft.com/en-us/openspecs/office_protocols/ms-sdpext/d2c16650-cefb-4f77-acbe-b958e909135b
[MS-SDPEXT]: Negotiating SRTP or SSRTP Optionally | Microsoft Learn
To require SRTP encryption for a media stream, an application can use the SRTP, as specified in [RFC4568], to specify the
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