Abstract: The invention provides a method of controlling transmission of packets from a transmitter to a receiver via a channel, and a corresponding transmitter and receiver. The method comprises: transmitting packets from a queue, each packet having a packet size based on data in the packet; determining a transmission time for each packet, based on a transmission clock; determining a reception time of each packet, based on a reception clock; supplying to an estimation function successive sets of observations including in each set transmission time, reception time and packet size, the estimate function being arranged to provide an estimate of bandwidth for the channel using the relationship between the bandwidth, the amount of data in the queue, packet size and the delay between transmitting successive packets from the queue; and using the estimated bandwidth to control transmission of packets.

Abstract: A node, such as a session node including any network node, located in a first network transmits data to one of a plurality of devices located in a second network. A determination is made that another device connected to the node is located in the second network. The node transmits to the other device located in the second network a message addressed to the one of said plurality of devices via the connection between the node and the other device effective to cause the message to be forwarded from the other device to the one of said plurality of devices via a connection established within the second network.

Abstract: A user of a first packet-based communication network is authorised to access a second packet-based communication network. In at least some embodiments, an authorisation request is received from a user terminal of the user at a first network element of the first packet-based communication network, the authorisation request comprising a first user identity. Responsive to the authorisation request, a request is transmitted to create a second user identity from the first network element to a second network element of the second packet-based communication network. The second network element creates the second user identity for use in the second packet-based communication network, the second user identity being derivable from the first user identity according to a predetermined rule. The second user identity in the second packet-based communication network is stored for use with subsequent communication events over the second packet-based communication network.

Abstract: A method of controlling quality of video data transmitted from a first user terminal to at least one other user terminal in a communication system includes detecting at said first user terminal a condition that indicates that the quality of the video data is below an acceptable threshold; automatically generating instructions based on the detected condition for a user of the first user terminal, said instructions intended to provide a humanly implementable remedy to improve the quality of the video data; outputting the instructions to the user in a humanly comprehensible form; and receiving an input from a user of the first user terminal responsive to the instructions to implement the remedy and thereby improve the quality of the video data.

Abstract: A method, program and user node for use in a communication system implemented over a network comprising a plurality of user nodes, each being associated with a respective presence status indicating an availability of the user node for communication within the communication system. The method comprises, at each of a first one or more of the user nodes: transmitting repeated presence messages to each of a plurality of others of the user nodes, each of the presence messages comprising at least one of: a request for the presence status of the other user node, and a notification of the presence status of the first user node; determining a measure of resource usage in relation to at least one of the first user node and the other user nodes; and controlling a regularity of the repeated transmission of presence messages in dependence on the determined measure of resource usage measure.

Abstract: A method of transmitting a communication event from a calling entity to a called entity located in a communication network comprising a first network and a second network, said method comprising determining a first identity associated with the called entity, wherein the first identity is recognizable in the first network; allocating a calling identity to the called entity, wherein the allocated identity is recognizable in the second network; associating at a first node located in the first network the first identity with the calling identity; providing the calling identity to the calling entity; establishing a connection with a second network node located in the second network; wherein the connection with the second network node is established using the calling identity, querying the first node with the calling identity associated with the called entity to determine the first identity associated with the called entity; transmitting the communication event to the called entity using the first identity associat

Abstract: A method of sorting communication events at a user terminal connected to a communication network and executing a communication client arranged to be operable by a user is provided. The method comprises storing an event list comprising a list of identifiers, each identifier having information relating to at least one previously received communication event associated therewith, wherein the identifier identifies the initiator of the associated at least one previously received communication event and each identifier is listed only once in the list of identifiers. The event list is displayed in a user interface of the communication client. The method further comprises receiving an incoming communication event at the user terminal from an initiating user over the communication network and determining whether the initiating user is present in the list of identifiers stored in the event list.

Abstract: A method of transmitting video, a method of receiving and decoding video, and a corresponding transmitter, receiver and computer program products. The method of transmitting video to one or more recipient terminals comprises: transmitting a stream of inter frame encoded video data to a recipient terminal; during ongoing transmission of the stream to the recipient terminal, receiving a request signal from that recipient terminal; and in response to the request signal, transmitting alternatively encoded video data to the recipient terminal in association with the inter frame encoded video data.

Abstract: An echo component of a first signal received at an audio input device is removed. A second signal is output from an audio output device. The echo component in the first signal is the result of the second signal traversing an echo path. The characteristics of the first and second signals are compared, and if the first signal only comprises the echo, an estimate of the echo path is determined by comparing the first and second signals. The echo path estimate is applied to the first signal to determine an equalised first signal, which is is compared with the second signal to determine an estimate of the echo component. The echo component from the first signal is removed in dependence on the estimate of the echo component.

Abstract: A method of encoding one or more parent blocks of values, the number of values being the length of each block, the method comprising for each parent block: (a) determining a first sum of values in the parent block; 1(b) splitting the parent block into smaller subblocks; (c) for at least one of the subblocks, determining a second sum of the values in the subblock, selecting a likelihood table from the plurality of likelihood tables based on said first sum of values in the parent block and encoding the second sum using the likelihood table; (d) designating each subblock a parent block; (e) carrying out steps (a), (b), (c) and (d) until at least one parent block reaches a predetermined condition.

Abstract: A user terminal connected to a communication network executes a communication client. The user terminal displays a list of contacts associated with a user of the client, and retrieves a message from the communication network, wherein the message is related to a further user represented by one of the contacts displayed in the list of contacts. The message includes a reference to media accessible by the communication network. The reference may be extracted from the message. A visual representation of the media may be displayed in association with one of the contacts, such that, responsive to the user actuating the visual representation, the client establishes communication with storage means using the reference and displays the media to the user.

Abstract: A method for generating a sequence of concealment samples in connection with transmission of a digitized audio signal, wherein the method comprises generating the sequence of concealment samples from buffered samples of the digitized representation of audio signal in sample time order, wherein at least two consecutive subsequences of samples in the sequence of concealment samples are based on subsequences of buffered samples, wherein said subsequences of buffered samples are consecutive in reordered time.

Abstract: A device for use in a communication system the device comprising processing means arranged to execute first and second applications, and first and second interface means, the first application for detecting a communication event, the second application comprising means for controlling the second interface to allow a user to use the second application; wherein the first application is arranged to control first interface means to indicate to a user of the device that the communication event has occurred, when the second application is running.

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 of processing a signal received at a node in a network, comprising the steps of; receiving the signal at the node; determining characteristics of a first part of the signal; determining characteristics of a second part of the signal that is subsequent to the first part of the signal; quantifying an effect on the signal caused by applying an action to the first part of the signal, based on characteristics of the first part of the signal; quantifying an effect on the signal caused by not applying the action on the first part of the signal, based on characteristics of the second part of the signal; applying the action to the first part of the signal if it is determined that the effect on the signal caused by applying the action to the first part of the signal is less detrimental to at least one measure of the signal quality than the effect on the signal caused by not applying the action to the first part of the signal.

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 terminal for use in a voice communications system includes a base station and at least one handset arranged to communicate wirelessly with the base station. The base station includes a first interface to a packet data network and a second interface to a public switched telephone network, the base station being arranged to selectively establish a packet data call from the first interface and a public switched telephone call from the second interface.

Abstract: A method of delivering an encoded data stream to a plurality of recipient end-user nodes of a network includes receiving an incoming encoded data stream at a first recipient node from a transmitting node over the network. During ongoing receipt of the incoming encoded data stream at the first recipient node from the transmitting node, the incoming encoded data stream is decoded at the first recipient node to produce a decoded data stream that is output for consumption at the first recipient node. The decoded data stream is used to generate a modified encoded data stream being a modified version of the incoming encoded data stream. Still during ongoing receipt of the incoming encoded data stream at the first recipient node from the transmitting node, the modified encoded data stream is relayed from the first recipient node to one or more second recipient nodes over the network.

Abstract: A method of transmitting messages from a network node in a communication network to a first user device can be provided. The network node transmits to a second user device a message-waiting notification. The first user device is identified, and a node holding the message is identified. In response to that notification, the second user device transmits a connection request to the first user device. The connection request is acted on by the first user device to establish a connection. With the identified node, the message can be optionally transmitted to the first user device.

Abstract: A method of transmitting data from a node, such as a session node including any network node, located in a first network to one of a plurality of devices located in a second network, said method comprising; determining that another device connected to the node is located in the second network; transmitting from the node to the other device located in the second network a message addressed to the one of said plurality of devices via the connection between the node and the other device; and forwarding the message from the other device to the one of said plurality of devices via a connection established within the second network.