This Recommendation specifies the requirements for the support of the flow state aware (FSA) transfer capability in a Next Generation Network (NGN). The FSA transfer capability provides QoS controls that operate on a per-flow basis, allowing flows to receive different treatment 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 at each FSA node. Service options that may be selected include requested support of the highest available end-to-end (or FSA edge-to-edge) rate for data transfer. Another option is immediate transmission, wherein a flow may start or assume a new rate immediately on the understanding that the network will provide a guaranteed rate as soon as possible. This will be provided when network resources permit. Yet another option is for a negotiated guaranteed rate. These services are targeted at access scenarios where media flows may result in temporary congestion and where best effort would not act selectively on the last few flows that had contributed to the onset of congestion. These services may also be applied to flow aggregates, providing the possibility of highest available rate between the aggregation end-points or the option of supporting immediate aggregate rate changes that act in conjunction with per-flow controls.