Abstract: An asynchronous switching node is described for distributing cells from an input port (I1, . . . , IN) of a node (ND) to a group of output ports (LG1, . . . , Lgk) thereof. The asynchronous switching node includes switching stages (S1, S2, S3) each having a switching element (S11, . . . , S3N) with inlets (IP1-IPN) and outlets (OP1-OPN). Each switching element (S11, . . . , S3N) has a routing logic circuit (MC1; MC2; RL) for routing one of the cells from one of the inlets (IP1-IPN) of one of the switching element (S11, . . . , S3N) to one of the outlets (OP1-OPN) thereof based on an internal routing label (LGA; SRT) associated with a cell. The switching element (S11, . . . , S3N) uses the internal routing label (LGA; SRT) to identify at least one distribution tree having branches (BR1, . . . , BR6 ) which connect the input port (I1, . . . , IN) with the group of output ports (LG1, . . . , Lgk).

Abstract: A cell resequencing system is provided for a resequencing section (RS) of a telecommunication network through which cells of communications are transmitted. The resequencing section includes cell switching networks (SN2) having inlets (I2l/I2n/I2N) coupled to inputs (S1l/S1n/S1N) and outlets (N2l/N2m/N2M). The cells are subjected to a first variable time delay. The cell resequencing system (C1l/C1n/C1N, CK1; R2l/R2m/R2M, CK2) includes latches (R2l/R2m/R2M) coupled between the outlets (N2l/N2m/N2M) and the outputs (S2l/S2m/S2M) to subject the cells to a second variable time delay chosen for each cell so the sum of the first and second variable time delay is substantially equal to a predetermined constant time value, which determines the size of the latches (R2l/R2m/R2M). The resequencing section (RS) has two inputs (S1l, S1n/S1N) each coupled to a distinct inlet (I2l/I2n/I2 N) via a distinct transmission link (TLl/TLn/TLN).

Abstract: Routing logic (RL) for a communication switching element (ISE) of a self-routing multi-stage switching network and able to transfer cells or packets of information from any of its inlets (I1/32) to any of its outlets (O1/32). The outlets of the switching element are arranged in routing groups containing one or more of them and of which the identity is derived by the routing logic from an output-port-address (OPA) identifying an output of the switching network and contained in the self-routing-tag (SRT) associated to the cell. This cell is then transferred to one of the outlets belonging to the selected routing group. The routing logic (RL) is also able to control the transfer of a cell through the switching element according to the execution of a predetermined routing function selected amongst a plurality of routing functions (RS, DI, MC, BH, IS).

Abstract: A telecommunication system for transmitting cells through switching nodes (N1-3) interconnected by groups (LG12, LG23) of transmission links, each node including an asynchronous switching network (SN1-3) which comprises several switch elements. At least one of these switch elements possesses a routing group possibility whereby the cells are distributed over its outlets and so further over the different transmission links of the link group to which the switching network is connected. This distribution is performed in function of a self-routing tag which is derived from external routing data associated with the cell. At the input ports of either each or only the first switching network (SN1) of the system, the external routing data is translated in a self-routing tag which is for instance added to the header of the cell, while at the output ports of each or of only the last switching network (SN3) of the system respectively, the self-routing tag is removed from this header.

Abstract: Resequencing system for a switching node (SN) of a cell switching system wherein cells or packets, of fixed or variable length, transmitted from an input to an output of a switching network (SNW), are subjected in the network to variable initial time delays for instance because they follow different paths therein. To restore at the output the sequence with which the cells were supplied to the input the cells at the output are subjected to additional variable complementary time delays which are so chosen that for each cell the sum of the two time delays is substantially equal to a predetermined total value.