"This Recommendation provides the signalling format and procedures for the flow state aware (FSA) transfer capability in a bounded subnetwork of a next generation network (NGN). The FSA transfer capability provides QoS controls that operate on a per-flow basis@ allowing flows within a bounded subnetwork of an NGN to receive different treatments depending on signalled parameters. These parameters are requested using in-band signalling. The parameters contained in these signals are included in the ""flow state"" maintained on each flow (or each aggregate flow)@ at each FSA node. Out of scope are any FSA edge functions at the network domain boundaries needed for interworking between two FSA networks@ where one uses in-band signalling exclusively for all FSA service support and the other uses both out-of band signalling (for resource reservation and clear down) and in-band signalling (to establish the agreed flow state). FSA signalling must not be used in the core network as it impacts on the scalability."