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The SNIA Shared Storage Model
The fact that there is a lack of any unified terminology for the description of storage architectures has already become apparent at several points in previous chapters. There are thus numerous components in a storage network which, although they do the same thing, are called by different names. Conversely, there are many systems with the same name, but fundamentally different functions.
A notable example is the term ‘data mover’ relating to server-free backup (Section 7.8.1) in storage networks. When this term is used it is always necessary to check whether the component in question is one that functions in the sense of the 3rd-party SCSI Copy Command for, for example, a software component of backup software on a special server, which implements the server-free backup without 3rd-party SCSI Copy Command.
This example shows that the type of product being offered by a manufacturer and the functions that the customer can ultimately expect from this product are often unclear. This makes it difficult for customers to compare the products of individual manufacturers and find out the differences between the alternatives on offer. There is no unified model for this with clearly defined descriptive terminology.
For this reason, in 2001 the Technical Council of the Storage Networking Industry Association (SNIA) introduced the so-called Shared Storage Model in order to unify the terminology and descriptive models used by the storage network industry. Ultimately, ...
