IP storage is a general term for several approaches to using the Internet Protocol (IP) in a storage area network (SAN) usually over Gigabit Ethernet. IP storage is an alternative to the Fiber Channel framework of the traditional SAN. Proponents of IP-based storage claim that it offers a number of benefits over the Fiber Channel alternative, and will promote the wide-spread adoption of SANs that was predicted when they were first introduced. Although SANs have been around since the mid-to-late 1990s, they haven't enjoyed the market acceptance that developers expected. Fiber Channel issues, including expense, complexity, and interoperability issues are frequently cited as the cause. According to proponents, IP storage provides a solution to these issues that will enable the SAN to fulfill its early promise.
For example, taking advantage of common network hardware and technologies may make IP SANs less complicated to deploy than Fiber Channel. The hardware components are less expensive, and because the technologies are widely known and used there are few interoperability issues and training costs are lower. Furthermore, the ubiquity of TCP/IP networks makes it possible to extend or connect SANs worldwide. There are several technology alternatives currently used for IP SANs: iSCSI (Internet SCSI) replaces Fiber Channel, while alternatives such as iFCP (Internet Fiber Channel Protocol) and FCIP (Fiber Channel over IP) offer hybrid approaches that can be used to extend Fiber Channel frameworks and to migrate from them to an IP storage network.
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