Question: What is the mandated protocol for transporting CMPv2 messages between network elements and Registration Authority (RA)/Certification Authority (CA), according to Network Domain Security (NDS) specifications?
Option 1: FTP (File Transfer Protocol) with optional TLS (Transport Layer Security)
Option 2: HTTP-based protocol as specified in IETF RFC 6712, with mandatory TLS support
Option 3: HTTP-based protocol as specified in IETF RFC 6712, without mandated TLS support
Option 4: SMTP (Simple Mail Transfer Protocol) with built-in encryption
Explanation: The correct answer is Option 3 because CMPv2 messages are to be transported using an HTTP-based protocol as outlined in IETF RFC 6712, without mandated TLS support, highlighting flexibility in security implementation while ensuring basic transport reliability via HTTP.