Question: What is the primary purpose of the Za-interface in Network Domain Security (NDS), and what protocol is used for authentication/integrity protection and encryption?
Option 1: To protect NE-NE interfaces within the same security domain, using TLS for authentication and encryption.
Option 2: To secure NDS/IP traffic between security domains, utilizing ESP for authentication/integrity protection and recommended encryption, with IKEv2 for tunnel establishment.
Option 3: To manage roaming agreements between different security domains, employing PGP for data encryption.
Option 4: To enforce security policies on Zb-interfaces, using SSH for secure access.
Explanation: The Za-interface is specifically designed to cover all NDS/IP traffic between different security domains, ensuring the protection of inter-domain communications. ESP (Encapsulating Security Payload) is mandated for authentication and integrity protection, with encryption being recommended. IKEv2 (Internet Key Exchange version 2) is used for negotiating, establishing, and maintaining secure ESP tunnels between Security Gateways (SEGs) of different domains, highlighting its role in practical telecom scenarios for securing inter-domain NDS/IP traffic.