ITU-T Recommendations

ITU-T Rec. E.360.1, "Framework for QoS routing and related traffic engineering methods for IP-, ATM-, and TDM-based multiservice networks", provides a framework for QoS Service Classes (QSCs), called virtual networks (VNETs) in the E.360.x series. QSCs are defined as aggregations of individual service classes. Instead of having per-class parameters being configured and propagated on each network interface, classes are aggregated into QSCs having common per-QSC parameters (e.g., maximum bandwidth) to satisfy required performance levels. QSCs are known as VNETs in TDM networks, class types in IP/MPLS/DiffServ networks, and QoS classes in ATM networks.In this Recommendation we identify QoS routing functions and associated parameters, which include: a) bandwidth allocation/protection, with traffic and QoS parameters;b) routing priority;c) queuing priority; andd) class-of-service identification, with service identity and QSC/VNET parameters.We propose means of signalling these QoS routing parameters across networks employing different routing technologies, including IP-, ATM-, and TDM-based routing technologies. We propose extensions to signalling protocols such as SIP and RSVP-TE to support signalling of QSCs within and across networks.