Abstract: A method of controlling a user device in a telecommunications network having a first part and a second, different part is provided. The method includes, at the user device, receiving a first communication session setup request to set up a given communication session, the first communication session setup request being directed to a first communication interface, receiving a communication notification in relation to the same given communication session, the communication notification being directed to a second communication interface, establishing the given communication session via the first communication interface via the first part of the telecommunications network, and after having established the given communication session via the first communication interface, activating an alert function to alert a user of the user device to the availability of the second communication interface at least on the basis of having received the communication availability notification.

Abstract: A method of providing failover processing between a first element and a second element in a data communications network, the method comprising configuring a first channel and a second channel between the first and second elements, the first and second channels comprising different physical data paths, receiving at the first element, via the first channel, first data signals representative of functioning statuses of the second element, the first channel being configured to allow a non-optimal, partly functioning status of the second element to be communicated to the first element; and receiving at the first element, via the second channel, second data signals representative of functioning statuses of the second element, the second channel being configured to allow a failed functioning status of the second element to be communicated to the first element; and conducting failover processing based on both the first and second data signals.

Abstract: Measures for use in processing communication sessions in a telecommunications network are provided. Each communication session has a signalling path spanning a plurality of devices including one or more intermediate network devices and at least two endpoint devices, the signalling path comprising a plurality of signalling segments, each segment being between two devices in the plurality of devices. A first signalling message, comprising a first identifier associated with the communication session, is received via a first signalling segment for a communication session. At least part of the first identifier is transformed using a deterministic encryption algorithm to generate a second identifier. A second signalling message, comprising the second identifier, is transmitted via a second signalling segment for the communication session to associate the second identifier with the communication session.

Abstract: A finite state machine is provided. The finite state machine causes a function to be carried out in dependence on at least an event input to the finite state machine and the current state of the finite state machine. Associations between the functions that are to be carried out and combinations of the states and the events are identified using an associative array. The associations identified using the associative array are amended while the finite state machine is operating to dynamically reconfigure the operation of the finite state machine.