Packet multiplex switching system

Abstract

Abstract 1. A system of commutation of multiplexes at intervals of time containing packets of fixed length originating from a plurality of n incoming junctions (E1, E2, ... E16) towards a plurality of n outgoing junctions (S1, S2, ..., S16) each incoming or outgoing packet having a heading plus n words, the system comprising : - first means MET for transmitting to the address inputs of a control memory programmable with aleatory access (MC), the heading and the identification of the incoming junction of origin of each incoming packet, the data output of the said control memory (MC) delivering a new translated heading allocated to the parallel incoming packet in substitution for the heading of origin so as to form with the remaining n words of the packet the parallel outgoing packet, - a buffer memory (M0, M1, ..., M16) activated cyclically in writing to memorize the outgoing packets, - second means of conversion (CTR1, CTR16) transforming each outgoing parallel packet read in the buffer memory in a series packet allocated to the addresses multiplexes, - a plurality of means (FS1, ..., FS16) to memorize the addresses of the packets which are present in the buffer memory (M0, M1, ..., M16) the said means being validated selectively in writing as a function of an item of information likewise supplied by other data outputs of the control memory, each of the means of memorization being allocated in a univocal manner to an outgoing junction and - means susceptible to a signal indicating the activation of any of the outgoing junctions in order to read the address contained in the corresponding means of memorization so as to find in the buffer memory the outgoing packet intended for the said junction, characterised in that it also comprises : - a time-base (ni) operating at a rhythm double the word output of the multiplexes and delivering n cyclic frames of 2n time intervals each, each frame being shifted by two intervals of time in relation to the preceding one, each outgoing junction being associated with one cyclic frame among n and each outgoing junction being associated with one cyclic frame among n, the first time of each frame validating the means for transmitting the heading of the incoming junction associated with the address inputs of the control memory (MC) the data output of which is connected to the first elementary memory M0 of the buffer memory, the following intervals of time of even rows validating successively the inputs of the n last elementary memories (M1 to M16) of the buffer memory, the first interval of time of a frame validating the liaison between the output of the first elementary memory (M0) and the second conversion means towards the outgoing junction associated with the said frame and the following intervals of time of even rows validating the liaisons between the outputs of the n last memories and the second conversion means towards the said associated outgoing junction.

Inventors

• 👤 Michel Servel
• 👤 Alain Thomas

Bibliographic Details