Performance Study of Buffer Control Schemes During Congestion in a Shared Buffer ATM Switch

Abstract

This paper considers overload control during congestion in a shared buffer ATM switch. To prevent performance degradation of the shared buffer memory switch under imbalance traffic conditions, a “gated” cell discarding policy is proposed. The concept of the “ gated” policy is that by adding a control gate in front of the logical queue pertaining to each overloaded output port, some incoming cells destined for the overloaded ports can be blocked so making rooms in the shared buffer for accommodating incoming cells destined for the non-overloaded ports. Numerical results show that the proposed “gated “ scheme can not only satisfy the “fair” access requirement under network congestion conditions, but also reduce the total number of discarded cell thus increases overall performance.