Why and what is a SAN?

Computing is based on data. Data is the underlying resource on which all computing processes are based; it is a company asset. Data is stored on storage media, and is accessed by applications executing on a server. Often the data is a unique company asset. You cannot buy your data on the market, but rather you must create and acquire it day by day. To ensure that business processes deliver the expected results, they must have access to the data. Management and protection of business data is vital for the availability of business processes. Management covers aspects such as configuration, performance, and protection, which ranges from what to do if media fails, to complete disaster recovery procedures. In the mainframe environments, the management of storage is centralized. Storage devices are connected to the host, and managed directly by the IT department where a system programmer (storage administrator) is completely dedicated to this task. It is relatively straightforward and easy to manage storage in this manner. The advent of client/server computing created a new set of problems, such as escalating management costs for the desktop, as well as new storage management problems. The information that was centralized in a mainframe environment is now dispersed across the network and is often poorly managed and controlled. Storage devices are dispersed and connected to individual machines; capacity increases must be planned machine by machine; storage acquired for one operating system platform often cannot be used on other platforms.