New SAN solutions based on IP protocols and Gigabit Ethernet have been introduced to complement and, in some cases, replace traditional Fibre Channel products. Consequently, SAN architects now have additional options for implementing shared storage. As usual, though, separating practical facts from vendor fiction is a necessary first step in designing a viable SAN. This chapter examines the basic features of IP storage protocols and transports and provides a foundation for understanding the capabilities that IP SAN products can offer.
Mainstream data communications networks are based on Ethernet for physical transport and on TCP/IP for routing of data from source to destination. Ethernet and TCP