Question: In IMS networks, how do WebRTC IMS clients route messages between the WebRTC IMS Client (WIC) and Serving-Call Session Control Function (S-CSCF) during session management procedures?
Option 1: Directly via the P-CSCF (Proxy-Call Session Control Function)
Option 2: Via the eP-CSCF (enhanced Proxy-Call Session Control Function), bypassing the P-CSCF
Option 3: Through a dedicated WebRTC Application Server (AS)
Option 4: Using standard SIP routing without any CSCF involvement
Explanation: For WebRTC IMS clients, session management procedures follow standard IMS protocols but with a notable exception in message routing. Unlike traditional IMS clients that would route messages through the P-CSCF, WebRTC IMS clients specifically route all messages between the WIC and S-CSCF via the eP-CSCF, accommodating WebRTC-specific extensions related to media handling.