Buffer Management in the Sliding-Window (SW) Packet Switch for Priority Switching

Abstract

Switch and router architectures employing a shared buffer are known to provide high throughput, low delay, and high memory utilization. Superior performance of a shared-memory switch compared to switches employing other buffer strategies can be achieved by carefully implementing a buffer-management scheme. A buffer-sharing policy should allow all of the output interfaces to have fair and robust access to buffer resources. The sliding-window (SW) packet switch is a novel architecture that uses an array of parallel memory modules that are logically shared by all input and output lines to store and process data packets. The innovative aspects of the SW architecture are the approach to accomplishing parallel operation and the simplicity of the control functions. The implementation of a buffer-management scheme in a SW packet switch is dependent on how the buffer space is organized into output queues. This paper presents an efficient SW buffer-management scheme that regulates the sharing of the buffer space. We compare the proposed scheme with previous work under bursty traffic conditions. Also, we explain how the proposed buffer-management scheme can provide quality-of-service (QoS) to different traffic classes.