Abstract: A method and system is described that adjusts the allocated capacity of a network between services, or service or traffic classes, in dependence on a congestion-influenced shadow price indication in respect of each service or class. In this respect, instead of viewing the congestion price as a cost of using already allocated unit of capacity, such a shadow price indication can be viewed as an indicator of the value obtainable from allocating an extra unit of capacity to a service or class. By so doing the shadow price indication becomes a factor to be taken into account in deciding on capacity allocation between services or classes, with a high shadow price indication for a service or class indicating that additional value would likely be obtained by allocating an additional unit of capacity to the service or class.

Abstract: A network has a plurality of edge nodes (7a, 7b, 7c, 7d) and core nodes (3a, 3b, 3c) for carrying flows of data from an ingress gateway (7a, 7b, 7c, 7d) to an egress gateway (7a, 7b, 7c, 7d) along a path of core nodes. For any given path in the network work from an ingress node to an egress node, the number of flows is controlled. When network congestion occurs, the egress gateway (7a, 7b, 7c, 7d) provides an indication of the level of network congestion. Terminating flows is disruptive and therefore the ingress gateway (7a, 7b, 7c, 7d) can mark other flows with a congestion marker and send them to the egress gateway (7a, 7b, 7c, 7d). These marked flows are routed by the core and egress gateway (7a, 7b, 7c, 7d) but ignored for calculating network congestion. When the network congestion is alleviated, the marked flows can be un-marked and treated as normal flows, hence the network avoids unnecessary flow termination.

Abstract: Methods and systems for providing information relating to congestion at a network element caused by data units intended to be forwarded across a telecommunications network by the network element, the apparatus comprising: load-data receiving means for receiving load data relating to data units intended to be forwarded by the network element; rate-data obtaining means for obtaining data indicative of a configurable rate; first and second registers for storing first and second metrics; first and second updating means operable to update the metrics in said first and second registers in dependence on said load data and on the configurable rate; and a congestion indication provider operable to provide indications of congestion in dependence on the metrics stored in the registers; said apparatus being configured in such that it may provide behavior equivalent to a virtual queue marking scheme by virtue of a minor modification to hardware provided for Single Rate Three Color Marking.

Abstract: A method and system is described that adjusts the allocated capacity of a network between services, or service or traffic classes, in dependence on a congestion-influenced shadow price indication in respect of each service or class. In this respect, instead of viewing the congestion price as a cost of using already allocated unit of capacity, such a shadow price indication can be viewed as an indicator of the value obtainable from allocating an extra unit of capacity to a service or class. By so doing the shadow price indication becomes a factor to be taken into account in deciding on capacity allocation between services or classes, with a high shadow price indication for a service or class indicating that additional value would likely be obtained by allocating an additional unit of capacity to the service or class.

Abstract: A network has a plurality of edge nodes (7a, 7b, 7c, 7d) and core nodes (3a, 3b, 3c) for carrying flows of data from an ingress gateway (7a, 7b, 7c, 7d) to an egress gateway (7a, 7b, 7c, 7d) along a path of core nodes. For any given path in the network work from an ingress node to an egress node, the number of flows is controlled. When network congestion occurs, the egress gateway (7a, 7b, 7c, 7d) provides an indication of the level of network congestion. Terminating flows is disruptive and therefore the ingress gateway (7a, 7b, 7c, 7d) can mark other flows with a congestion marker and send them to the egress gateway (7a, 7b, 7c, 7d). These marked flows are routed by the core and egress gateway (7a, 7b, 7c, 7d) but ignored for calculating network congestion. When the network congestion is alleviated, the marked flows can be un-marked and treated as normal flows, hence the network avoids unnecessary flow termination.

Abstract: Embodiments of the invention provide a network management sub-system which is preferably logically separate from the routing nodes (including gateway nodes) of a network. The network management sub-system receives load information relating to present packet flows on existing predetermined paths in the network, and when a request for admittance of a new packet flow is received, is able to make a decision as to whether the new flow should be both: i) admitted to the network; and ii) on to which path; in substantially the same process step. This is possible because the admission control and routing algorithms are integrated into a single process, the result of which provides both an admission control decision as well as a routing decision at the same time.

Abstract: In embodiments of the invention when a session request is received the value assigned to that session is compared to present congestion costs in the network at the present time. If the value of the session exceeds the cost then the session is accepted; otherwise it is rejected. It is possible to show mathematically that, provided this strategy is used for all session requests, then, when demand exceeds supply for a given resource, the congestion measurement for that resource rises to become equal to its shadow price. Here, in a model of a capacity constrained network, the shadow price of a capacity constraint is the cost to other users of using one unit of capacity. Congestion measurements can therefore be used to provide a “cost” (to other users) of admitting the flow to the network, which can then be compared against the “value” (to the network operator) of admitting the flow during the admission control evaluation. Additionally, this “cost” vs.

Abstract: Methods and systems for providing information relating to congestion at a network element caused by data units intended to be forwarded across a telecommunications network by the network element, the apparatus comprising: load-data receiving means for receiving load data relating to data units intended to be forwarded by the network element; rate-data obtaining means for obtaining data indicative of a configurable rate; first and second registers for storing first and second metrics; first and second updating means operable to update the metrics in said first and second registers in dependence on said load data and on the configurable rate; and a congestion indication provider operable to provide indications of congestion in dependence on the metrics stored in the registers; said apparatus being configured in such that it may provide behaviour equivalent to a virtual queue marking scheme by virtue of a minor modification to hardware provided for Single Rate Three Colour Marking.