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CAS cost considerations
Upfront and ongoing costs associated with each CAS product should be considered; as data grows, the hidden costs/savings of these architectures will become more apparent. Purchasers of RAIN products from Archivas, Bycast, EMC, HP and Permabit should expect to pay as little as $7,500 for a 1.5TB configuration to as much as $350,000 or more for a 50TB setup.
Permabit is the only vendor with two pricing models: per node or by capacity. The per-node option, also offered by Bycast, EMC and Permabit, will probably be the less-expensive option because capacity on CAS products could scale into the petabytes. Per-node licensing is also more favorable for products such as Bycast's StorageGrid, which support portable media such as tape, which requires fewer nodes to house data.
There are exceptions, of course. Users who anticipate keeping data from different departments or customers on separate nodes may find licensing by total capacity to be cheaper. Users also need to examine what storage optimization features, if any, they'll turn on and if that will control data growth.
In the future, it's likely CAS products will emerge as the preferred means of managing structured and unstructured retention data. The four CAS options--RAIN, file system, HSM and storage architectures--all allow users to start small, scale economically and satisfy the data-retention requirements that meet specific apps. But integrating CAS with various apps isn't
This was first published in June 2006