On the switch architecture for fibre channel storage area networks

The fast growth of data intensive applications has caused a change in the traditional storage model. The server-to-disk approach is being replaced by storage area networks (SANs), which enable storage to be externalized from servers, thus allowing storage devices to be shared among multiple servers. Nowadays, the majority of SANs use fibre channel. The standard for fibre channel defines several issues related to the switch interface, but does not make any suggestion about the internal switch architecture to be implemented by manufacturers. We analyze the key architectural switch characteristics for building fibre channel storage area networks. To do so, our starting point is the performance analysis of two different switch architectures, identifying their strongest and weakest points, and thus taking advantage of the best features from both of them. After this first analysis, we introduce several other features in the switch, concluding with a proposed architecture that doubles network throughput while reducing response delay.