ITU-T Y.2111 PDF

This Recommendation specifies the resource and admission control functions (RACF) in support of end-to-end quality of service (QoS) and network border control (at access-core and inter-domain boundaries) in next generation networks (NGNs). The RACF is aimed at providing real-time application-driven and policy-based transport resource management for a wide range of services and for a variety of transport technologies (fixed, mobile, etc.). Services can make use of RACF whether the IP multimedia subsystem is involved or not. This Recommendation defines the related requirements and functional architecture covering aspects such as resource reservation, admission control and gate control, network address port translation (NAPT) and firewall control, and network address translator (NAT) traversal.

It also defines the reference points between different functional entities and the pertinent stage 2 requirements and describes the procedures for QoS-related transport resource control, NAPT control and NAT traversal.

The pertinent protocol specifications are described in separate Recommendations. End-to-end information flows for representative applications, such as VoIP, bulk data transfer and video on demand, are for further study.

Note that network management functionality is outside the scope of this Recommendation.

Administrations may require operators and service providers to take into account national regulatory and national policy requirements in implementing this Recommendation.