Question: In the context of WebRTC IMS Client registration with an IMS network using web credentials, what type of authentication is required for interface W1 (WIC to WWSF) if the user's web identity is authenticated by the WAF?
Option 1: One-way authentication from WWSF to WIC
Option 2: One-way authentication from WIC to WWSF
Option 3: Mutual authentication between WIC and WWSF
Option 4: No authentication is required for this interface
Explanation: According to the security requirements for WebRTC IMS Client registration, if the user's web identity is authenticated by the Web Application Firewall (WAF), only one-way authentication from the WebRTC IMS Client (WIC) to the Web WebSocket Subsystem Function (WWSF) is required for interface W1. This ensures that the WWSF verifies the WIC's identity without necessitating a reciprocal verification, given the WAF has already authenticated the user's web identity.