Abstract: A search query to provide a search result may be received, which identifies source and target nodes and an application for generating the search result. The application accesses a data structure holding landmark nodes, which store a shortest path tree in the form of a set of parent links. Each parent link can identify an adjacent vertex node in a shortest path between each node in the data structure and the landmark node. The location of the source node and the target node in the shortest path trees may be identified to the landmark node. For each landmark node, using the identified locations of the target node and source node, a measure of distance between the source node and the target may be generated. The landmark node with the shortest distance may be determined. A search result related to the shortest path tree of that landmark node may be provided.

Abstract: A method of transmitting video data comprising: establishing a bidirectional video channel between a first terminal and a second terminal in a packet-based communication network; beginning a live, face-to-face video call over the established channel by generating first video data from a video camera of the first terminal, transmitting the first video data to the second terminal for display on a screen of the second terminal, receiving second video data generated from a video camera of the second terminal, and displaying the second video data on a screen of the first terminal; generating third video data at the first terminal from a source other than the video camera of the first terminal; receiving a user selection at the first terminal; and in response to the user selection, transmitting the third video data to the second user over the established channel of the packet-based communication network.

Abstract: According to an embodiment, there is provided a method of generating a data structure stored in computer memory for processing a search query in a network of interconnected nodes, wherein the method comprises selecting landmark nodes by the following steps and storing the selected landmark nodes in the data structure: sampling from the network nodes a first sample of vertex pairs, computing the shortest path for each vertex pair, each shortest path comprising a set of vertices between each vertex in the vertex pair; identifying a first landmark node which occurs in more of the shortest paths more often than any other vertex; removing from the network vertices shortest paths including the first landmark node and identifying a second landmark node which occurs in more of the remaining shortest paths than any other remaining vertex.

Abstract: Method, communications device and computer program product for determining network quality for the communications device which is capable of communicating over a communications network. The method comprises determining location information associated with a location of the device, querying a database using the determined location information, wherein the database stores a plurality of entries each comprising location information and corresponding network quality information, and obtaining, from the database in response to the query, network quality information from at least one entry of said entries which comprises location information corresponding to the determined location information.

Abstract: A method of placing an outgoing communication event to a destination phone number is disclosed. Accordingly, upon receiving a notification of the outgoing communication event, a determination is made if the destination phone number is associated with a user of a first network. The first network is a packet based communication network. A user identification of the user of the first network corresponding to the destination phone number is then retrieved. A presence information of a communication node in the first network associated with the user is also retrieved. The presence information is an indication of the user's availability. The communication node is configured to receive voice communication events. The outgoing communication event to the communication node associated with the user in the first network is placed based on the retrieved presence information.

Abstract: A media appliance and corresponding method, the media appliance comprising a video signal source such as a TV receiver, and signal processing apparatus for generating a corresponding sequence of frames for output to a screen. The appliance comprises a client application programmed to capture one of the frames and use the captured frame to generate an image to represent a user in relation to bidirectional communications over a packet-based network.

Abstract: A method, system and program for encoding speech.

Abstract: A method, system and program for transmitting different quality versions of a stream to end-user nodes of a network. The method comprises: for each of a plurality of possible combinations of versions of the stream to different consuming end-user nodes, evaluating a utility function for each of those consuming end-user nodes, the utility function being dependent on the version and defining a quantitative measure of end-user benefit that would be experienced at the respective end-user node by consumption of the respective version; for each of said plurality of possible combinations of versions of the stream over said routes, determining an overall utility value based on the respective evaluation of the utility functions of each of said plurality of consuming end-user nodes; and selecting a preferred combination of versions of the stream over said routes based on the overall utility values of the different possible combinations.

Abstract: A communication session between a user of a communication network and a communication system is controlled. The communication network comprises a first network and a second network. The communication system operates on the first network. A session request packet is transmitted from a device of the user to a first node in the first network. The session is initiated with the communication system at the first node responsive to receiving the session request. During the session, a calling identity is provided from the first node to the device and used by the device during a communication event between the user and an entity. The calling identity is used to establish a connection between the device and a second node in the second network. The calling identity is associated with an address of the entity. Upon termination of the session, the calling identity is disassociated from the address of the entity.

Abstract: A method system and program for encoding and decoding a speech signal including error correction data. The method comprises: receiving a speech signal comprising successive frames, for each of a plurality of frames of the speech signal, analysing the speech signal to determine side information and a residual signal, encoding the residual signal at a first bit rate, and generating an output bitstream based on the residual signal encoded at the first bit rate, and for at least one of the plurality of frames of the speech signal, encoding the residual signal at a second bit rate that is lower than the first bit rate; and generating error correction data based on the residual signal encoded at the second bit rate.

Abstract: A communication system comprising: a terminal having: an interface to a network, whereby the terminal can be connected to another party on a communication session; an output for outputting a communication stream received from another party on a communication session; and a source of play-out stream independent of a communication session; and a communication controller for managing a communication session terminated at the terminal, the communication controller being configured to: a) when it detects that the terminal has been placed on hold in a communication session, cause play-out stream from the source of play-out stream to be directed to the output; and b) when it detects that the terminal has been taken off hold in the communication session, cause communication stream from the communication session to be directed to the output.

Abstract: A method of associating a first device with a second device is disclosed. The first device through its speaker broadcasts a request for association using an audio signal. The broadcasted audio signal is received by the second device through its microphone. The first and second devices then cooperatively verifies a security code and upon a successful verification of the security code, the first and the second devices are enabled to communicate with each other.

Abstract: A method of pairing a first device with a second device is disclosed. Accordingly, an image that include encoded data is generated by the first device. The encoded data includes a unique identifier for identifying the first device and an arbitrary security code. The first device displays the image on a display. The second device captures the image using an image sensing device. The encoded data is decoded to generate a decoded data. The second device sends the decoded data to a server that is communicatively connected to the first device and the second device. Upon receiving the decoded data and using the unique identifier, the server communicates with the first device to verify the arbitrary security code.

Abstract: A method for reducing ringing in a signal output from a filter comprising inputting a signal into a filter; filtering a first portion of the input signal to generate a filtered portion of the output signal; analyzing the filtered portion of the output signal; detecting if ringing is present in the filtered portion of the output signal based on said analysis; and adjusting the filter characteristics to reduce ringing in a subsequent filtered portion of the output signal if it is determined that ringing is present.

Abstract: A method, system and computer program for encoding speech according to a source-filter model. The method comprises deriving a spectral envelope signal representative of a modelled filter and a first remaining signal representative of a modelled source signal, and deriving a second remaining signal from the first remaining signal by, at intervals during the encoding: exploiting a correlation between approximately periodic portions in the first remaining signal to generate a predicted version of a later portion from a stored version of an earlier portion, and using the predicted-version of the later portion to remove an effect of said periodicity from the first remaining signal. The method further comprises, once every number of intervals, transforming the stored version of the earlier portion of the first remaining signal prior to generating the predicted version of the respective later portion.

Abstract: A method of transmitting data from a first node to a second node in a communication network includes receiving a signal; dividing the signal into data elements arranged in a first data stream comprising active and inactive data elements; analysing at least one characteristic of the signal to determine if the signal is stable; dropping at least one active data element from a plurality of data elements of the first data stream if it is determined that the portion of the signal included in the plurality of data elements is stable; inputting the data elements that are not dropped from the first data stream into a core stream; and transmitting the core stream from the first node to the second node.

Abstract: A method and corresponding system for communicating over a network using a first device and a peripheral device, wherein the first device comprises a user interface and a network interface for connecting to the network, and the peripheral device has a local connection to the first device, the local connection being independent of the network. The method comprises receiving data packets from the network at the network interface of the first device and forwarding the received data packets from the first device to the peripheral device via the local connection. A client engine of a communication client is executed on a processor of the peripheral device to process the received data packets. Processed data packets are sent from the peripheral device to the first device via the local connection such that data contained in the received data packets is conveyed to a user of the first device using the user interface of the first device.

Abstract: Provided is a method of controlling traffic transmitted over a network path from a transmitter to a receiver via a router, the traffic comprising a plurality of packets, and the method comprising: at one of said transmitter and receiver, estimating a maximum queue length at a buffer of the router based on a maximum observed delay for traffic to travel from the transmitter to the receiver, and estimating a current queue length at the buffer of the router based on an observed delay for one or more specified packets to travel from the transmitter to the receiver; and based on said estimates of current queue length and maximum queue length, controlling traffic between the transmitter and receiver over said network path.

Abstract: A communication system, method and client program for communicating via a first network. The system comprises a first network and a router coupling the second network to the first network, the router comprising an address translator configured to map second-network addresses to a lesser number of first-network addresses identifying the second user nodes collectively to the first network. Each of the second user nodes is installed with a communication client configured so as when executed on the second user nodes to: compare the first-network addresses of two of the user nodes, and, if their first-network addresses match such that both are nodes of the second network, communicate an availability status of one of the two user nodes between the two user nodes directly over the second network without routing via the first network.

Abstract: A method of communicating user activity in a messaging system. The method comprises: monitoring an input region displayed to a first user of the messaging system in a client executed at a user terminal of the first user; responsive to receiving a user activated input at the input region, analysing the input and using the analysis to match the input to a type of user activity from a predetermined set of user activities; and transmitting a message comprising data representing the type of user activity from the user terminal of the first user to a user terminal of at least one other user of the messaging system over a communications network.