Fujitsu Corporation

Nippon Telegraph and Telephone Public Corporation

Kenichi Hashimoto

Kenji Narita

Ikuo Taniguchi

A system for monitoring an ATM cross-connecting apparatus by rewriting a VPI conversion table to various values, inputting a test cell, and examining the test cell after the test cell passes through the ATM cross-connecting apparatus. Entries of a VPI conversion table are accompanied by traffic flags indicating whether or not the corresponding entry is occupied for use for user's signals. First, the traffic flags are examined. Each entry not occupied for user's signals can be freely rewritten. Each entry occupied for user's signals is not rewritten. The examination of the test cell is carried out by comparing the test cell output from the ATM cross-connecting apparatus, with a reference cell which is expected from a normal operation of the ATM cross-connecting apparatus. The virtual path identifier converted in the ATM cross-connecting apparatus and contained in the output test cell, is expected corresponding to the above rewriting operations, and is contained in the reference cell.

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Kawasaki, Japan

Kenichi Hashimoto