Telecommunication system with transport protocol device for mixing asynchronous signaling traffic with TDM traffic on a TDM backbone

A telecommunications system comprising a plurality of servers interconnected by a high speed TDM backbone defining a plurality of timeslots, said servers being able to share a common channel or bandwidth, a master node for sending a stream of cells capable of carrying asynchronous data in the form of control messages round the backbone, each said cell having a header portion and a payload portion, a plurality of downstream nodes which upon arrival of incoming cells insert information therein, read information therefrom, or allow said cells to pass thereby unaltered, a high-speed framer on said backbone is connected to an interface device for time division miltiplexed delay-sensitive traffic and to a transport protocol circuit generating said stream of cells and performing format, mapping and MAC functions to interface said cells to said TDM backbone, said interface device generating control signals to control the transmission of cells from said transport protocol circuit to said framer so as to permit the co-existence of time division multiplexed delay sensitive traffic from said interface device and asynchronous delay non-sensitive signaling, traffic from said transport protocol circuit on said TDM backbone in a bandwidth-on-demand environment.