ATM exchange

Abstract

The ATM exchange of the present invention comprises an input line interface and an output line interface. The input line interface comprises an FRM extractor for deciding whether each ATM cell sent from a first communication terminal to a switch is an FRM cell or a non-FRM cell, an FRM cycle monitor for using this decision result to monitor the FRM cell proportion among the ATM cells and deciding whether said proportion is normal or abnormal, and a first cell processor for discarding the non-FRM cells when the proportion is abnormal. The output line interface comprises a BRM extractor for deciding whether each ATM cell sent from a communication terminal to a switch is a BRM cell or a non-BRM cell, a BRM cycle monitor for using this decision result to monitor the BRM cell proportion among the ATM cells and deciding whether said proportion is normal or abnormal, and a second cell processor for discarding the non-BRM cells when the proportion is abnormal. When the FRM cycle monitor decides that the quantity of flow of FRM cells has decreased, the first cell processor discards the non-FRM cells and returns the proportion of FRM cells to its normal state. When the BRM cycle monitor decides that the quantity of flow of BRM cells has decreased, the second cell processor discards the non-BRM cells and returns the proportion of BRM cells to its normal state.

Dependencies are inferred from the claim text.