Cell switch and cell switch network using dummy cells for simplified cell switch test in communication network

A cell switch for switching cells entering from a plurality of input transmission paths to a plurality of output transmission paths according to a routing information indicated in a header of each cell, the cell switch comprising:

• buffer memory means, connected with the input transmission paths and the output transmission paths, for storing the cells entered from the input transmission paths;
• buffer memory control means for controlling writing and reading operations with respect to the buffer memory means according to the routing information indicated in a header of each cell;
• dummy cell generation means for generating dummy cells in correspondence to the output transmission paths, said dummy cells outputted to the output transmission paths and monitored during a test for testing connections of the cell switch;
• and
• output control means for selectively outputting the dummy cells generated by the dummy cell generation means to the output transmission paths when the test for testing connections of the cell switch is indicated by an externally provided control signal supplied to the output control means, and selectively outputting the cells outputted from the buffer memory means to the output transmission paths otherwise.

A cell switch network comprising:

• a plurality of inter-connected cell switches for switching cells entering from a plurality of input transmission paths to a plurality of output transmission paths according to a routing information indicated in a header of each cell, each cell switch including:
• buffer memory means, connected with the input transmission paths and the output transmission paths, for storing the cells entered from the input transmission paths;
• buffer memory control means for controlling writing and reading operations with respect to the buffer memory means according to the routing information indicated in a header of each cell;
• dummy cell generation means for generating dummy cells in correspondence to the output transmission paths, said dummy cells outputted to the output transmission paths and monitored during a test for testing connections of the cell switch;
• and
• output control means for selectively outputting the dummy cells generated by the dummy cell generation means to the output transmission paths when the test for testing connections of the cell switch is indicated by an externally provided control signal supplied to the output control means, and selectively outputting the cells outputted from the buffer memory means to the output transmission paths otherwise.