The steady and fast increase of data intensive application is violently driving the demand for more data storage capacity and new storage architecture. The server-attached storage approach is being replaced by storage area networks (SANs), whose primary purpose is the transfer of data between computer systems and storage elements or among storage elements, allowing storage devices to be shared among multiple servers. In this paper, we mainly analyze the different characters of Fibre Channel, iSCSI and InfiniBand used within the SANs environment. This paper discusses the issues of protocol performance, protocol scalability, the security mechanism, the interoperability and adaptability with SAN environments, the cost of investment of each architecture and so on. Comparing the performance of traditional direct attached storage, the findings show that all Fibre Channel, InfiniBand and iSCSI are the competent gigabit networking technology for storage area networks. Each protocol has its own advantages and disadvantages. Due to the overwhelming benefits of economy, covenience and high performance/cost ratio, more enterprise can deploy iSCSI SAN based on mature and existing TCP/IP infrastructure.