MODULAR EXPANDABLE SINGLE STAGE DIGITAL ATM SWITCHING NETWORK FOR HIGH SPEED PACKET-SWITCHED INFORMATION TRANSFER

摘要

A modularly expandable digital single-stage ATM (Asynchronous Transfer Mode) switching network for high-speed packet-switched information transfer, comprising a single type of switching module with storage function which can be operated by two different operating modes (M1, M2) as preprocessing module or as final processing module and has N first inputs, N expansion inputs, N first outputs and N expansion outputs. A first operating mode (M1) implements the function of the switching module as final processing module for switching N first-input lines and N expansion-input lines to N first-output lines, and a second operating mode (M2) implements the function of the switching module as preprocessing module for pre-processing N first- input lines and for switching-through N expansion-input lines. The switching module operating as preprocessing module can simultaneously enter two N packets and simultaneously read out N packets. The switching module operating as preprocessing module only processes a part of the overhead information of data packets with its overhead information filter for switching the packets to the relevant switching matrix column so that the lines of the matrix column are used jointly by packets for this matrix column. To avoid so-called overtaking by packets, the order in time of packets in each case arriving on one of the N first-input lines of the switching module operating as preprocessing module is replaced case by case by a spatial order on the N first-output lines of the switching module operating as preprocessing module. The switching module operating as final processing module can simultaneously enter 2 N packets. The switching module operating as final processing module processes a different part of the overhead information with its overhead information filter (KF) for the final switching to a matrix output.