Abstract: A node (50) for a communications system comprising a network of a plurality of nodes is described. The node (50) communicates with other nodes (50) in the network using information formatted into superframes comprising a plurality of symbols in which part of the superframes are for payload data and part of the superframes are for synchronisation data and such that there is agreement amongst at least some nodes of the network of when a superframe starts and the duration of the symbols of the superframe. The node (50) synchronises its reference source (60,61) to a selected synchronisation source selected from external synchronisation sources and changes the selection of external synchronisation source from time to time such that the selected synchronisation source availability and reliability is above a predetermined level and communications data of a superframe is interpretable while the node (50) communicates with at least some of the other nodes (50) in the network.

Abstract: A set of wireless nodes is provided, in which a subset of the wireless nodes are also wired nodes. A method of processing the set comprises performing a node initialisation, thereby linking nodes in the set of wireless nodes, performing a link evaluation, thereby determining a quality characteristic of links between nodes, and segmenting the nodes into partitions, each partition comprising at least one wired node and each node in a partition having a link to another node in the same partition with the determined quality characteristic above a predetermined threshold.

Abstract: In a communications system a transmitter is arranged to transmit asynchronous transfer mode (ATM) cells in which synchronous transfer mode (STM) channels are assembled. In order to minimize the bandwidth required at lease some of the ATM cells include one or more switch command(s) (12) that indicate a change in the activation state of one or more STM channels (11-0 to 11-n). The switch commands (12) and STM channels (11) fill the ATM cell from opposite ends of the cell. Activate switch commands comprise two bytes, a high byte including a pointer (18) pointing to the start of a block of STM channels (11) and a low byte that includes a pointer (19) that points to the channel within a block of STM channels (11) to which the switch command applies.

Abstract: In a communications system a transmitter is arranged to transmit asynchronous transfer mode (ATM) cells in which synchronous transfer mode (STM) channels are assembled. In order to minimise the bandwidth required at lease some of the ATM cells include one or more switch command(s) (12) that indicate a change in the activation state of one or more STM channels (11-0 to 11-n). The switch commands (12) and STM channels (11) fill the ATM cell from opposite ends of the cell. Activate switch commands comprise two bytes, a high byte including a pointer (18) pointing to the start of a block of STM channels (11) and a low byte that includes a pointer (19) that points to the channel within a block of STM channels (11) to which the switch command applies.