Abstract: A messaging system is provided for communicating a message between a first communications unit having a first messaging entity and a second communications unit having a second messaging entity, each messaging entity having a messaging call control means for establishing a messaging communications link with the other messaging entity; and a messaging means for, once the messaging communications link has been established, exchanging messaging information with the said other messaging entity. Also a method is provided for communicating a message between a first communications unit and a second communications unit, the first communications unit having an application layer, a messaging entity and a network layer.

Abstract: A DECT fixed part for providing a communications link between a DECT portable part and a GSM mobile switch center, the fixed part comprising a compression negotiation means for: receiving from one of the portable part and the mobile switch center a first message specifying a form of compression for a data service; and using that first message, determining a second message to be sent to the other of the portable part and the mobile switch center to request it to adopt a corresponding form of compression for the data service; so as to allow the provision of a compressed data service between the portable part and the mobile switch center.

Abstract: A DECT communication system having; at least one portable part; and a fixed part for connection to a GSM interworking unit of a GSM communication system and capable of wireless communication with the portable part to provide data service communications between the portable part and the GSM interworking unit; and including converting means for converting between data service signals at the portable part and signals in ISDN format, so as to provide data service communications between the DECT communications system and the GSM interworking unit at a data rate greater than 9600 bps.