Question: In the context of WebRTC IMS Client authentication with an IMS subscription, what type of authentication is required for the interface W2 (WIC to eP-CSCF) according to security requirements?
Option 1: Mutual Authentication
Option 2: One Way Authentication (eP-CSCF authenticates WIC)
Option 3: One Way Authentication (WIC authenticates eP-CSCF)
Option 4: No Authentication Required
Explanation: Mutual authentication for the W2 interface is crucial as it ensures both the WebRTC IMS Client (WIC) and the eP-CSCF verify each other's identities. This enhances security by preventing impersonation attacks on either end, which is particularly important in IP-based services where secure signaling connections are paramount.