WebRTC traffic has to be translated to SIP in order to communicate with the edge. The "Gjoll" servers (part of the Genesys Cloud microsystems) are on the internet...no way to keep that traffic on the LAN.
SRTP can have a direct path to the Premises Edge. See section E of the detailed diagram:
https://help.mypurecloud.com/articles/detailed-webrtc-diagram/
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George Ganahl GCP, GCSME, ICCE, ICHD, etc.
Senior Principal PS Consultant
Genesys
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