Storage and Mirroring in Single and Dual Section Metro WDM Rings under Different Traffic Scenarios

Abstract

This paper introduces a novel data mirroring technique for storage area networks (SANs) in a metropolitan wavelength division multiplexing (WDM) ring scenario. Sectioning links are introduced to the ring to help deal with the hot node (SAN node on ring) scenarios created by the SANs and their mirrors. Two network architectures are studied: The first architecture accommodates conventional access nodes and a single SAN and its mirror, the latter connected through a sectioning link. The other architecture accommodates conventional access nodes and two pairs of SANs and their mirrors with a sectioning link connecting each pair. Simulation is carried out to evaluate the performance of both architectures under the proposed mirroring technique for a 24 node architecture with 1 Gb/s access node rate and 5 Gb/s SAN node rate and under two different traffic models– Poisson and selfsimilar. In addition to the fixed-size (FS) slot scheme, performance is evaluated under two different slot schemes accommodating variable size packet traffic — variable-size (VS) and super-size (SS) slot schemes. Simulation Results of average node throughput and queuing delay are presented and analyzed.