Abstract: A method of authenticating a device subscribed to a first wireless communication network on a second wireless communication network, the method including: deriving at a node within the first wireless communication network a set of one or more network keys for the second wireless communication network from one or more network keys of the first wireless communication network that uniquely identify the device within the first wireless communication network; communicating the derived set of one or more network keys to the device; storing a first copy of the derived set of one or more network keys within an identification module at the device and a second copy of the derived set of one or more network keys within a secure area of the device; and authenticating the device on the second wireless communication network using the second copy of the derived set of one or more network keys stored in the secure area of the device.

Abstract: This invention relates to methods and systems for searching. It is particularly applicable to methods of searching which enable efficient identification of compatible portfolios. Embodiments of the invention propose methods of searching which address the huge search space issue associated with identifying compatible portfolios. In particular, embodiments of the invention start their search operations simultaneously from both sides by both trying to form valid portfolios from candidate products until a valid solution is found and trying to find conflicts from the defined compatibility rules until a conflict is found which leads to the conclusion that no valid solution exists. A conclusion from either process will stop the whole searching process which can significantly reduce blind and unnecessary searching in the whole search space.

Abstract: This invention relates to end-to-end transparent clocks and methods of estimating skew in end-to-end transparent clocks. Embodiments of the invention relate to techniques for estimating clock skew between a free-running clock in a transparent clock and a master clock, in particular by using the timing information embedded in timing messages passing through the transparent clock. Further embodiments of the invention set out uses of these estimates to modify the residence times computed by the transparent clock and a synchronization network including such transparent clocks.

Abstract: This invention relates to peer-to-peer transparent clocks and methods of estimating skew in peer-to-peer transparent clocks. Embodiments of the invention relate to techniques for estimating clock skew between a free-running clock in a transparent clock and a master clock, in particular by using the timing information embedded in timing messages passing through the transparent clock. Further embodiments of the invention set out uses of these estimates to modify the residence times computed by the transparent clock and a synchronization network including such transparent clocks.

Abstract: An assignment system for allocating service providers to required services, comprising: a data processing unit; a data store storing a plurality of allocation processing routines each defining a respective algorithm for determining in respect of a service which of a series of potential providers of that service is/are preferred to provide the service; and an allocation mode selector configured to access a data store storing a list of required services and attributes of each required service, to select in dependence on the attributes of one of those services one of the allocation processing routines and to cause that allocation processing routine to be executed in respect of that one of the services by means of the data processing unit so determine which of a series of potential providers of the service is/are preferred to provide that service.

Abstract: A computer implemented method for generating a pattern matching machine for identifying matches of a plurality of symbol patterns in a sequence of input symbols, the method comprising: providing a state machine of states and directed transitions between states corresponding to the plurality of patterns; applying an Aho-Corasick approach to identify one or more mappings between states in the event of a failure, of the state machine in a state and for an input symbol, to transition to a subsequent state based on the directed transitions of the state machine, characterised in that one of the symbol patterns includes a wildcard symbol, and a mapping for a state representing pattern symbols including the wildcard symbol is provided in a hash table referenced based on a key, the key being based on a unique identifier of the state and the input symbol to be received, by the pattern matching machine in use, to constitute the wildcard symbol.

Abstract: This invention relates to methods and devices for timing synchronization. The invention has particular application where timing is being carried out over packet networks using, for example, the IEEE 1588 Precision Time Protocol (PTP). Embodiments of the invention make use of estimated forward and reverse path delay asymmetries directly in the estimation algorithm (for example a Kalman filter). This can allow the variation in the timestamps which have been compensated for the delay asymmetry to be significantly reduced, which can reduce the complexity of the phase offset estimation algorithm.

Abstract: A method for designating a class of data content for determining how the content will be handled by a content delivery network (CDN) into one of: a transport designation by which content is transported from an entrance node to one or more edge nodes; a caching designation by which the content is stored at one or more edge nodes; and a hybrid designation by which content is stored at a node in the CDN for subsequent transport to one or more edge nodes in the CDN, the method comprising: determining a set of one or more transport designation options; determining a set of one or more caching designation options; determining a set of one or more hybrid designation options; determining a normalised measure resource requirement for each of the transport, caching and hybrid designation options; and selecting one designation option for the class of content from all of the transport, caching and hybrid designation options by an optimisation function for selecting the designation option based on the determined normalise

Abstract: A method for generating a pattern matching machine for identifying matches of a symbol pattern in a sequence of in put symbols, the received symbol pattern including an indicator that one or more symbols in the symbol pattern repeat as repeated symbols, the method comprising: generating a plurality of symbol patterns for the received symbol pattern, each generated symbol pattern being equivalent to the symbol pattern for a different number of repetitions of the repeated symbols, wherein the plurality of generated symbol patterns comprise all possible symbol patterns equivalent to the received symbol pattern up to a predetermined maximum length of a generated symbol pattern.

Abstract: This invention relates to methods and systems for controlling appliances, particularly climate control appliances such as air conditioning units used in buildings. Embodiments of the invention provide methods and systems which provide a framework of semi-autonomous sensors and actuators which can achieve climate control without the need for centralised or explicit coordination. In certain embodiments, the climate control system is capable of identifying suitable pairings of sensors and actuators and taking into account actions of other actuators. The embodiments have particular application in buildings where large numbers of individual sensors and actuators are deployed in an ad-hoc or unplanned manner over time, but can communicate with each other. The embodiments of the invention can provide improved efficiency, reduced infrastructure costs, improved flexibility and can be deployed across multiple sites.

Abstract: This invention relates to methods and systems for estimating offset, skew and drift. Embodiments of the invention relate to methods and systems which allow these relationships between a slave clock and a master clock to be estimated based on the exchange of timestamped messages between the master and the slave. Further embodiments of the invention set out uses of these estimates to synchronize a local clock in a slave to a master and to steer the slave clock to stay aligned to the master clock when the master clock is temporarily unavailable or the communication path between slave and master is temporarily unavailable.

Abstract: This invention relates to methods and systems for optimizing network catchment areas, in particular based on completion times of the customer premises. Embodiments of the invention aggregate different customer premises to form demarcated catchment areas by minimizing the overall weighted cost function comprising the distance and completion time within each catchment area, while also considering practical constraints. Embodiments of the invention allow network planners to specify their preferences of distance against time to produce cost-effective network schemes for very large numbers of customer premises and form network catchment areas without any overlapping.

Abstract: A method for generating a pattern matching machine for identifying matches of a plurality of symbol patterns in a sequence of input symbols, the method comprising: providing a state machine of states and directed transitions between states corresponding to the plurality of patterns; applying an Aho-Corasick approach to identify mappings between states in the event of a failure, of the state machine in a state and for an input symbol, to transition to a subsequent state based on the directed transitions of the state machine, characterized in that one of the symbol patterns includes a wildcard symbol, and mappings for one or more states representing pattern symbols including the wildcard symbol are based on an input symbol to be received, by the pattern matching machine in use, to constitute the wildcard.

Abstract: This invention relates to methods and systems for monitoring mobile service quality in a mobile network and also for determining parts of a mobile network which need expansion or upgrade. Embodiments of the invention monitor the market impact and/or service quality, and determine an expansion ranking. The market impact, service quality and/or expansion ranking may view the network from a plurality of perspectives, including a location perspective, an historical time perspective, a future time perspective and/or a network element type perspective. The results of the monitoring and determining can be acted on by predetermined rules and/or actions to derive a list of prioritized expansion tasks for the network.

Abstract: A method of comparing the semantic similarity of two different text phrases in which the grammatical structure of the two different text phrases is analyzed and a keyword set for each of the different text phrases is derived The semantic similarity of the phrases can be determined in accordance with the grammatical structure of the two different text phrases and the contents of the two keyword sets.

Abstract: The invention provides an apparatus for processing data items in a data source, and an equivalent method. More specifically, the apparatus is configured to reduce a lattice representation of data items in a data source. The apparatus has a processor that is operable to retrieve data items from the data source and to determine a context defining relationships between data items and one or more properties associated with the data items. An initial lattice data structure is generated based on the determined context. The processor then reduces the size of the lattice by dividing the initial lattice data structure into a plurality of subgroup lattice, reducing the size of each of the subgroups of lattice, and combining them to form a reduced lattice data structure.

Abstract: This invention relates to methods and systems for estimating skew based on, for example, the IEEE 1588 Precision Time Protocol (PTP). These methods and systems can allow the clock skew between a master clock (server) and slave clock (client) exchanging PTP messages over a packet network to be estimated more rapidly than conventional estimation techniques and thereby improve the convergence of standard estimation algorithms. In one embodiment, the skew estimation is derived from a set of timestamps from a message exchange between the master and slave using a non-linear least square-fitting algorithm. An example of the fitting algorithm is the Levenberg-Marquardt algorithm.

Abstract: This invention relates to methods and systems for localization. It is particularly concerned with localization techniques based on time difference of arrival for wireless devices. Embodiments of the invention relate to techniques in which a transmitter transmits periodic distinguishable signals which are relayed upon receipt by the client whose location is sought in a form distinguishable from that of the transmitter. Signals from both the transmitter and the client are received by at least three signal receivers which generate a time difference of arrival based on the difference taken for a signal to reach the receiver directly and via the client. Further embodiments of the invention provide a phase detector in the receivers to determine the time difference of arrival between the signals.

Abstract: This invention relates to methods and systems for estimating offset and skew using linear programming. Embodiments of the invention relate to methods and systems which apply linear programming principles to links with asymmetric transmission rates which are estimated from an exchange of timing messages (for example under IEEE 1588 PTP). Further embodiments provide for the estimation of clock offsets using linear programming techniques when the skew is known or estimated.

Abstract: This invention relates to methods and devices for bias estimation and correction, particularly for time-of-arrival (TOA) based wireless geolocation systems. Multipath and non-line-of-sight (NLOS) biases can cause distance estimation errors in the range of tens-hundreds of meters and is particularly problematic in urban and indoor environments. The behavior of the biases dynamically changes depending on the clutter and/or obstructions between the base station and the mobile device. Aspects of the present invention provide practical real-time bias estimation and correction techniques for TOA-based systems and are based on inferring and estimating the biases from dynamic time differential measurements. The techniques can operate in real-time and involve simple calculations.