The traditional storage business models of NAS and SAN have been worthwhile for many enterprises, but the question remains: Is NAS or SAN (or some combination of both) best for cloud computing environments? Scality, a storage vendor with offices in San Francisco, Paris and Tokyo, asserts that, in many cases, the answer is no. Scality's RING "organic storage software" is, according to the company, the first object-based storage platform to provide the levels of performance necessary for robust Web-based applications.
Scality’s target customers are public email providers and public cloud providers, although large enterprises could use RING for a private cloud. The data best served by RING is not structured data--that is, relational database residing/managed information, such as that found in mission-critical online transaction processing systems. Instead, Scality focuses its efforts on unstructured data, which the company defines as anything from emails and word processing documents to photos and videos.
For purposes of this discussion, I will accept Scality's definition of unstructured, although I differentiate between semi-structured file (such as word processing documents) and unstructured files (such as videos).
Now, the volume of unstructured information greatly outweighs that of structured data in enterprises and clearly dominates consumer markets, so there is and
will continue to be plenty of data to manage.
Note that for the purposes of providing online storage services for unstructured data, the IT architecture, including the storage architecture, of public cloud service providers is a black box to the user. That means that the end user generates well-defined inputs (for example, a request for a specific piece of information) and receives well-defined outputs (getting back the requested information) with the required service levels, such
as low latency from the time that the request is made until it is satisfied, and high reliability that the specified delivery will be met. But all of this is performed out of sight, if not out of mind, of the end user.
You could think of it in terms of what my good friend Peter Keen, the well-known IT consulting guru, told me many years ago: Technology should be "mundane and opaque." To Peter, mundane means that the technology should be easy to use, while opaque means that you have no idea how the technology works. The bottom line is the user neither knows, nor should he or she care, what IT architecture the service provider uses.
This means that the service provider is not locked into choosing traditional network-attached storage/storage area network (NAS/SAN) technology unless it wants to, but can choose virtually any architecture so long as it supports the service’s performance and service-level agreement (SLA) requirements. Scalilty argues that the service provider should use multiple server/storage nodes, where a portion of the overall storage is inside each server as dedicated direct-attached storage (DAS) arrays.
Note that this back-to-the-future DAS model is antithetical to the concept of shared storage as found in a conventional SAN.
So how does this architecture work? How does a user, who may be anywhere in the "cloud," access his or her data? How does the system deliver the required performance?