Abstract: A method of attributing contributions to congestion of a shared resource to respective user registers, the resource being operable to serve requests for service, each of a plurality of the requests having a user indication associated therewith indicating with which of a plurality of user registers the request is associated.

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 an associated traffic management module and system are disclosed for monitoring, at a traffic management module (26) within a data network, path characterisation information indicative of at least one measure of a dynamic network characteristic at a remote node (23) outside said data network. The method involves a traffic management module (26) receiving at least one data unit from a remote node (23) outside said data network, and in the event that said at least one data unit is encapsulated in an outer header and that an inner header of said data unit includes path characterisation information, performing the following in respect of said data unit: (a) monitoring said path characterisation information in said inner header; and (b) forwarding said data unit according to a first treatment category. In the event that these conditions are not met, the data unit is instead subjected to an alternative treatment.

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: A method of attributing contributions to congestion of a shared resource to respective user registers, said resource being operable to serve requests for service, each of a plurality of said requests having a user indication associated therewith indicating with which of a plurality of user registers the request is associated.

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 an associated traffic management module and system are disclosed for monitoring, at a traffic management module (26) within a data network, path characterisation information indicative of at least one measure of a dynamic network characteristic at a remote node (23) outside said data network. The method involves a traffic management module (26) receiving at least one data unit from a remote node (23) outside said data network, and in the event that said at least one data unit is encapsulated in an outer header and that an inner header of said data unit includes path characterisation information, performing the following in respect of said data unit: (a) monitoring said path characterisation information in said inner header; and (b) forwarding said data unit according to a first treatment category. In the event that these conditions are not met, the data unit is instead subjected to an alternative treatment.

Abstract: Data networks and nodes making up parts of data networks are arranged to derive information relating to the characterization of paths taken by data travelling between nodes in the networks. Path characterization information is fed back from a receiver of data to a provider of data, and informs nodes subsequently forwarding data of characteristics of the downstream path. Also described are routing and related controlling nodes and methods for using such path characterization information to make informed routing and other decisions when forwarding data in a data network.

Abstract: Methods and systems for determining origin-specific network metrics in respect of a data network having at least one ingress node, the method comprising: receiving data items from outside the network; forwarding the data items with headers comprising fields for carrying origin information relating to the origin of the data item, and path metric information indicative of a characteristic being monitored; causing the data items to traverse the network; updating the fields carrying path metric information as the data items traverse the network; determining the origin information and path metric information after the data items have traversed the network and deriving in dependence thereon an origin-specific path metric relating to the characteristic in respect of the relevant portion of a path across the network; and combining origin-specific path metrics derived in respect of different data items if they relate to characteristics in respect of data items having a common origin.

Abstract: Methods, apparatus and other means for providing path characterisation information 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 having associated therewith information indicative of the network characteristic, the path being traversed by the data units having at least a first path portion between said 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 being 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 of codepoints.

Abstract: The invention provides a method of managing the braking of an aircraft having a plurality of brakes comprising friction elements, the method comprising the following steps for at least one group of brakes: estimating an energy level (?E) to be dissipated by the brakes of the group; and estimating individual braking setpoints (Fi) for each of the brakes of the group so that the individual braking setpoints make it possible, at least under normal operating conditions of the brakes, to implement braking that dissipates said energy level, the individual braking setpoints also being determined so as to satisfy at least one other given operating objective.

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: A braking control method that includes: (1) regularly updating a grip model representative of a relationship between a coefficient of friction and a wheel slip rate; (2) determining, with an iterative calculation process including a plurality of calculation cycles a variation of a braking setpoint in a given prediction horizon, the variation of the braking setpoint in the given prediction horizon being established using the regularly updated grip model and its characteristic shape and so that the variation of the braking setpoint in the given prediction horizon complies with the braking order and complies with a given calculation constraint which is function of the wheel slip rate; and (3) retaining as the generated braking setpoint a value of the braking setpoint in the given prediction horizon which corresponds to a first calculation cycle of the plurality of calculation cycles of the iterative calculation process.

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: 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 characterisation information relating to a network characteristic such as network congestion to nodes in a data network (10) using data units being forwarded from a source (11) to a destination (19) via a plurality of nodes (15) in the network, the method comprising: receiving, at a first proxy node (13), data units from a source (11), each data unit comprising a destination indication indicative of an intended destination; identifying, in respect of an intended destination indicated, a second proxy node (17) 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 (15); the method further comprising assigning conditions to path characterisation metrics in respect of data units traversing a path across the network from the first to the second proxy node, the initial condition being depende