What is a valid class included in the 8-class QoS strategy in a VoIP network?

Assured Forwarding (AF) is a defined Per-Hop Behavior (PHB) within the Differentiated Services (DiffServ) architecture. It allows for grouping traffic into different classes, and within each class, packets can be marked with different drop precedence values, providing a level of assurance that packets will be delivered as long as the offered load does not exceed certain rates. This is a common component of QoS strategies, including those supporting VoIP.

'Broadcast video' is a type of application, not a standard QoS class or PHB in the 8-class model. Traffic for broadcast video would be mapped to one of the defined QoS classes.

'Multimedia conferencing' is a type of application, not a standard QoS class or PHB. Its traffic would be categorized into specific QoS classes (e.g., EF for voice, AF for video).

'Real-Time Interactive' is a descriptive category for certain applications (like voice or video conferencing), but it is not a direct QoS class name or PHB itself within standard QoS frameworks like DiffServ. Expedited Forwarding (EF) is the PHB typically used for real-time voice.