Abstract: Congestion in respect to a network element operable to forward data items in a telecommunications networks, and in respect to a processing element operable to process requests for service is signaled. In either, the element is operable to perform its processing function at up to a processing rate which is subject to variation, and has a queue for items awaiting processing having a counter associated therewith which maintains a count from which a queue metric is derivable. A method comprises: updating the count at a rate dependent on the processing rate; further updating the count in response to receipt of items awaiting processing; and signalling a measure of congestion in respect of the element in dependence on the queue metric; then altering the rate at which the count is being updated and adjusting the counter whereby to cause a change in the queue metric if the processing rate has changed.

Abstract: Methods and apparatus for controlling the forwarding of a flow (12) of data units across a network from a sender node (11) to a receiver node (19) via at least one intermediate node (15), the data units each having one of a plurality of different types of class indication associated therewith, each type of class indication providing, to an intermediate node currently processing the data unit with which the class indication is associated, an indication denoting a particular class of treatment, selected from a plurality of different classes of treatment, according to which the data unit is to be processed by that intermediate node, such that different proportions of the data units of the flow are forwarded as different sub-flows each comprising data units having class indications of different types thereby providing indications denoting different classes of treatment.

Abstract: The present invention provides a method and system wherein congestion information is taken from a lower level in the protocol stack and used for congestion marking in a higher layer. In particular, the method and system of the invention from a first aspect provide for congestion information in the lower layer to be generated downstream at a congested node, and to be fed back upstream to a source node. The source node then passes the congestion information, or information derived therefrom, up to the corresponding network element responsible for higher layer functions in the protocol stack, where higher level congestion marking can then be performed in dependence on the received lower level congestion information. Thus, congestion information from the lower layer which can typically be generated earlier before significant congestion occurs can be used in higher layer congestion control functions. Preferably the lower layer is the data link layer, and the higher layer is the network layer.

Abstract: A method of call control in which a first communications network, detecting calls directed to a destination in the first network; redirects at least some of the calls to a destination in a second network (e.g. on no answer from the destination in the first network). The first communications network obtains from a client on a terminal associated with the destination in the second network a value for the time delay before a call to the destination in the second network is redirected in the second network on no answer to an alternative destination and sets a delay period to a value less than the value of the time delay obtained from the client. When one of the plurality of calls redirected to the second network is not answered in the second network within the delay period, the first communications network redirects the call to an alternative destination associated with the first network.

Abstract: Methods and apparatus for controlling the forwarding of a flow (12) of data units across a network from a sender node (11) to a receiver node (19) via at least one intermediate node (15), the data units each having one of a plurality of different types of class indication associated therewith, each type of class indication providing, to an intermediate node currently processing the data unit with which the class indication is associated, an indication denoting a particular class of treatment, selected from a plurality of different classes of treatment, according to which the data unit is to be processed by that intermediate node, such that different proportions of the data units of the flow are forwarded as different sub-flows each comprising data units having class indications of different types thereby providing indications denoting different classes of treatment.

Abstract: A method of routing packets in a packet network is disclosed. The packet network includes a chain of packet nodes, the chain comprising a first and second access node for communicating with one or more mobile nodes and one or more intermediate packet nodes providing a path interconnecting the first and second access nodes. Previous methods are inefficient and lead to additional overhead.

Abstract: A method of call control in which a first communications network, detecting calls directed to a destination in the first network; redirects at least some of the calls to a destination in a second network (e.g. on no answer from the destination in the first network). The first network then operates in two phases. In a first phase, for a group of calls redirected to the second network, the time delay before the call is answered in the second network is recorded. When a number of time delays have been recorded, a delay period is set to a value less than the maximum value of the recorded time delays. In a second phase, for a second group of calls redirected to the second network subsequent to the calls of the first group, when a call of the second group is not answered in the second network within the delay period, the call is redirected to a message service associated with the first network.

Abstract: A method of call control in which a first communications network, detecting calls directed to a destination in the first network; redirects at least some of the calls to a destination in a second network (e.g. on no answer from the destination in the first network). The first network then operates in two phases. In a first phase, for a group of calls redirected to the second network, the time delay before the call is answered in the second network is recorded. When a number of time delays have been recorded, a delay period is set to a value less than the maximum value of the recorded time delays. In a second phase, for a second group of calls redirected to the second network subsequent to the calls of the first group, when a call of the second group is not answered in the second network within the delay period, the call is redirected to a message service associated with the first network.

Abstract: A method of call control in which a first communications network, detecting calls directed to a destination in the first network; redirects at least some of the calls to a destination in a second network (e.g. on no answer from the destination in the first network). The first communications network obtains from a client on a terminal associated with the destination in the second network a value for the time delay before a call to the destination in the second network is redirected in the second network on no answer to an alternative destination and sets a delay period to a value less than the value of the time delay obtained from the client. When one of the plurality of calls redirected to the second network is not answered in the second network within the delay period, the first communications network redirects the call to an alternative destination associated with the first network.

Abstract: A telecommunications system includes a mobile network having a plurality of portable communication devices, and a fixed network which includes a signaling agent, a plurality of directory agents, and a plurality of spaced apart attachment points to which the mobile network can attach. In use, each directory agent stores a routing table for routing data to a respective mobile communication device associated with that directory agent. When the point of attachment of the mobile network changes, the mobile network sends a change-of-address message to the signaling agent. In response, the signaling agent is configured to forward the change of address to each directory agent, so that each can update its routing table to take into account the changed point of attachment of the mobile network.

Abstract: The present invention provides a method and system wherein congestion information is taken from a lower level in the protocol stack and used for congestion marking in a higher layer. In particular, the method and system of the invention from a first aspect provide for congestion information in the lower layer to be generated downstream at a congested node, and to be fed back upstream to a source node. The source node then passes the congestion information, or information derived therefrom, up to the corresponding network element responsible for higher layer functions in the protocol stack, where higher level congestion marking can then be performed in dependence on the received lower level congestion information. Thus, congestion information from the lower layer which can typically be generated earlier before significant congestion occurs can be used in higher layer congestion control functions. Preferably the lower layer is the data link layer, and the higher layer is the network layer.