Industry specialists have been warning for some years that the amount of data being produced by the increasing use of IT is logarithmically increasing, and that serious management attention is required. As IT has moved from being used in selective areas of business to becoming a general tool in all areas of a business this increase in the production of data is understandable. The need for more efficiency in straight forward storage is clear enough, but this is only the most obvious part of the changes required. In the first three months of 2003, during a time of economic and budget cut backs, according to IDC, globally organisations increased their storage capacity by buying an additional 175.6 Petra bytes of storage space. This equates to an extra 49% of capacity, mostly bought without any strategic justification, purely a cost within the IT budget based on current ‘needs’. The suppliers of storage products, the IT industry and CIOs cannot continue just to provision more ‘space’.
After more than thirty years of Direct Attached Storage, or DAS, being at first the only, and latterly the leading way of storing data, relatively quickly over the last five years of new purchases Network based storage has taken over as the dominate form. Though there is competition as to whether this should be achieved using Storage Area Networks, SANs, the leading technique, or Network Attached Storage, NAS, the shift is clear, and follows a distinctive change in the way that IT is supporting business by using Networked Devices. SAN storage is architecturally attuned to, and deployed as, a part of three layer, or ‘N’ tier, solutions built with Application Servers. It is the accelerating change to building solutions in this manner, for the many benefits that it provides, that accounts for the switchover in sales from application centric DAS, to process centric SAN.