Summary

This Recommendation defines the H.323 Quality of Service (QoS) and Service Priority signalling for exchanging, negotiating and controlling QoS and service priority parameters among the H.323 entities in a call. These calls may involve multiple network operator domains, multiple service domains, and heterogeneous transport mechanisms (e.g., mixed IP, ATM, and MPLS environments). In a single network operator domain or H.323 service domain, the QoS policies and mechanisms are usually homogenous and therefore the negotiation and establishment of QoS for a call is relatively simple. However, the same is relatively more complex when a call has to traverse multiple service or network domains each of which has its own set of policies and mechanisms. This Recommendation describes the QoS and priority signalling to enable a H.323-based call to acquire QoS irrespective of the number of domains it traverses.