Question: In a 5G Core Network using Service-Based Architecture (SBA), what extension in an X.509 certificate can indicate its purpose for different uses, such as TLS authentication or JSON signing/encryption?
Option 1: Subject Alternative Name (SAN) extension
Option 2: Basic Constraints extension
Option 3: Extended Key Usage (EKU) extension
Option 4: Authority Key Identifier (AKI) extension
Explanation: The Extended Key Usage (EKU) extension in an X.509 certificate indicates the purpose for which the certificate can be used, such as TLS authentication, code signing, etc. In a 5G Core Network with SBA, the EKU extension validates certificate usage for various purposes, including JSON Web Signature and JSON Web Encryption, although specific identifiers are subject to ongoing standardization efforts.