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: Apparatus and methods for policing flows of data units (15) along a path in a data network in dependence on congestion indications associated with said data units indicating whether or not said data units have experienced, or are expected to experience, congestion on the path, said apparatus and methods allowing for a high but not unlimited short-term burst rate (wST) of data units having congestion indications associated therewith, the short-term burst rate being high when compared with a long-term average rate (wLT) at which data units having congestion indications associated therewith may be forwarded without the data units being subjected to a policing action such as dropping, delaying or marking for possible sanction.

Abstract: Methods and apparatus for providing path characterization information relating to a network characteristic such as network congestion to nodes in a data network using data units being forwarded from a source to a destination via a plurality of nodes in the network, the method comprising: receiving, at a first proxy node, data units from a source, each data unit comprising a destination indication indicative of an intended destination; identifying, in respect of an intended destination indicated, a second proxy node in the network to which data units may be forwarded before being forwarded to the intended destination; and forwarding a first and at least one subsequent data unit from the first to the second proxy node via ‘one or more intermediate nodes; the method further comprising assigning conditions to path characterization metrics in respect of data units traversing a path across the network from the first to the second proxy node, the initial condition being dependent on information received by the first

Abstract: Methods and systems for policing usage by one or more users (12) of a data network (14), said one or more users (12) being able to send, to receive, or to send and receive data over the network via one or more of a plurality of access nodes (42), the usage of the data network resulting from respective data units consuming network resources along respective paths across the data network (14), each of said data units being associated with one of a plurality of subsets of the usage of the data network, said data units having congestion indications associated therewith indicating a measure of their congestion impact.

Abstract: Methods and systems for assigning information indicative of a network characteristic to one of a plurality of data units traversing a path across a network, said data units having associated therewith values indicative of said network characteristic, said path having at least one portion passing through a lower-capability region and at least one portion passing through a higher-capability region, said lower-capability region being a region in which information indicative of said network characteristic may be represented by values having a first resolution, and said higher-capability region being a region in which information indicative of said network characteristic may be represented by values having a second resolution, said second resolution being greater than said first resolution, said one data unit being a data unit entering said higher-capability region.

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: Data networks, nodes making up parts of data networks, and information are related to the characterization of paths taken by data travelling between nodes in the networks. Path characterization information is arranged to be conveyed to nodes such that it may be used by nodes subsequently forwarding data. In particular, the invention relates to nodes receiving such path characterization information from upstream nodes, deriving therefrom information indicative of characteristics of a path downstream of said nodes, and using such information to make informed decisions such as routing decisions when forwarding data onward in data networks.

Abstract: Path characterization information is provided to a data sender relating to a network characteristic such as congestion experienced by data units traversing a path across a data network from the data sender towards one of a plurality of data receivers. The data units have associated therewith information indicative of the network characteristic. The path is traversed by the data units having at least a first path portion between the data sender and a proxy node along which data units may traverse conveying a measure indicative of the network characteristic that is representable by any of a first set of codepoints. The data receivers are operable to provide data acknowledgement units in respect of data units they receive via a second path portion in which information indicative of the network characteristic may only be representable using codepoints of a second set of codepoints having less codepoints than the first set.

Abstract: Methods and apparatus for encoding a number of small dynamic values over an n-bit field. Also methods and apparatus allowing for the stateless extraction of separate sequences from repetitions of a single field whereby to communicate more than one signal at once.

Abstract: Methods and systems for determining a correction factor for use in monitoring network traffic, said network traffic comprising a plurality of flows of data units, each flow having associated therewith a flow identifier, said data units having associated therewith a path characterization metric; the method comprising the steps of: selecting a subset of flow identifiers from the overall set of flow identifiers; determining, in respect of flows having associated therewith flow identifiers from said selected subset of flow identifiers, which flows if any are persistently irregular flows; determining a first measure of the total of the accumulated path characterization metrics associated with data units of said selected subset of flows; determining a second measure indicative of the proportion of said total measure contributed by said persistently irregular flows; and determining a correction factor in dependence on the first and second measures.

Abstract: One or more users of a present state are notified of at least one property of an entity. A request message is received from a user over a first communications channel, the message containing information indicative of at least one property of an entity in which the user is interested. The present state of the at least one property is determined, as is an identifier of a second communications channel onto which future messages containing information relating to future changes of state of the at least one property of the entity will be transmitted. A reply message is transmitted to the user, the reply message containing information indicative of the present state of the at least one property and of the identifier of the second communications channel.

Abstract: Flow in a data network is policed by determining a measure of greediness of a flow through a node, comparing the measure of greediness with a measure indicative of acceptable greediness dependent on the expected greediness of a compliant flow experiencing substantially similar path conditions, and designating the flow for possible sanction in the event that the greediness is not in accordance with the acceptable greediness. Such allows for the policing of a data network when one or more fields in a data packet that carry information relating to a characterization of an end-to-end path and/or a downstream path of the data packet are used in order to police the data network.

Abstract: A processing node for processing data items in a data network, comprising means for receiving data items, means for receiving characterization metrics associated with the data items and identifying characteristic values in respect thereof, and a process selection means, said process selection means comprising means for deriving a collective value from characteristic values associated with a plurality of the data items, means for comparing characteristic values associated with a plurality of the data items with a predetermined target value, means for subjecting data items in respect of which the characteristic values are on a first side of the predetermined target value to a first process, means for selecting at least some of the data items in respect of which the characteristic values are on a second side of the predetermined target value, and means for subjecting the selected data items to a second process which is different from the first process.

Abstract: The invention provides a coordination layer of coordinating entities provided intermediate the admission control interfaces of the transport network domains, and any QoS signaller which signals QoS requests on behalf of the application layer. The coordination layer acts to distribute an admission control request across the multiple transport network domains by the use of coordination request messages containing the admission control request being forwarded through the coordination layer of coordinating entities. At each coordinating entity the admission control request is passed on to the admission control interface of the transport network which the coordinating entity serves, and an admission control response obtained. This admission control response is then combined with admission control responses from the other domains which are propagated through the coordination layer via coordination messages.

Abstract: In a communications network, use of network resources is measured locally at customer terminals, for example by counting the number of packets sent and received. The resulting data may be aggregated and sent to a network accounting object. Accounting data may subsequently be passed between network subdomains.

Abstract: An announcement thread addressing format which comprises a first sub-part concatenated with a second sub-part is described. The first sub-part is preferably the address of the party which generates the addressing identifier, whereas the second sub-part may be random data. An announcer apparatus may then use these address formats by including only those parts of an announcement thread address which render the address unique within the particular index message in which it is to be included, but not necessarily globally unique.

Abstract: A network channel is used as a waiting channel, wherein members of a group other than a first member join the waiting channel while performing an action or process, and then leave the waiting channel once the action or process has been performed. Once all of the members have left the waiting channel the first member of the group then performs an action or process. In order to indicate to the first member that all of the other members have left the waiting channel, a protocol such as the Multicast Source Notification of Interest Protocol (MSNIP) may be used.

Abstract: In a communications network, which may be a federated network such as the Internet, a tariff is distributed via the network to customer terminals. At each terminal a charge for use of the network is calculated by using the tariff. Different tariffs may be communicated for different services and a respective tariff may be varied depending upon the operational condition of the service. Different tariffs may be calculated for different customers and the tariffs may be varied in dependence upon the loading of network resources and different tariffs may have different volatilities. Part of the traffic from a user to the network may be sampled and the status of the user may be amended when a discrepancy is detected between the sampled parameters and the contracted parameters in the users contract.

Abstract: A network includes a server and a number of clients, which will in operation of the network require authentication by the server. The server distributes authentication information to other clients when a session is initialized. When the server needs to authenticate a client, it hands out a server request to the client which asks client for authentication information which it must obtain from other clients. The client to be authenticated then sends these requests to the clients specified in the authentication request to obtain the authentication information from those clients. Once the client to be authenticated has received the relevant authentication information from the other clients it returns it to the server and is authenticated or not accordingly.

Abstract: The invention relates to data networks, to nodes making up parts of data networks, and to information relating to the characterisation of paths taken by data travelling between nodes in the networks. Path characterisation information is arranged to be conveyed to nodes such that it may be used by nodes subsequently forwarding data. In particular the invention relates to nodes receiving such path characterisation information from upstream nodes, deriving therefrom information indicative of characteristics of a path downstream of said nodes, and using such information to make informed decisions such as routing decisions when forwarding data onward in data networks.