Question: For P/UDP/IP transport of continuous media in a telecom network, what is the requirement for supporting the Extended Profile for CP-based Feedback (/AVPF) in relation to retransmission?
Option 1: Mandatory support for /AVPF is required regardless of retransmission support.
Option 2: Support for /AVPF is optional and not tied to retransmission capabilities.
Option 3: A client or server must support the generic NACK message in /AVPF if retransmission is supported, but other feedback formats are not mandatory.
Option 4: /AVPF support is conditional on the implementation of a specific CP transmission interval.
Explanation: This option accurately reflects the nuanced requirement that while supporting /AVPF is recommended for continuous media transport, there's a specific condition for retransmission support: a client or server must support the generic NACK message if they offer retransmission, highlighting a balanced approach between flexibility and reliability in telecom networks.