STORAGE: A Case for CAS

Until now, the industry-wide embrace of storage networking and the rapid
coupling of countless petabytes of data have shaped conventional storage
thinking in two fundamental ways–storage improvements must always be faster
and cheaper, and complexity must be tolerated to achieve efficiency.

Such thinking is rooted in the build-out process that evolved storage
networks to where they are today–at the epicenter of a company"s business. But
new challenges posed by Web-based service models, increasing regulatory
requirements, heightened security, data preservation, and storage optimization
are edging out the old thinking, and bringing to light the value of an
architecture called content addressed storage (CAS).

CAS is key to business because it overcomes the threats posed by these new
storage challenges–the unmanaged, exponential growth in capacity and number of
fixed content objects.

By the end of next year, most of the data stored by every corporation and the
entire US government combined will be fixed content. Fixed content constitutes
stored files that should not be changed, updated, or modified when recalled. For
example: legal and securities documents, photographic archives, medical imaging
files, product and promotional shots, consumer check images, media
presentations, transit maps, and even instant messages. The daily flow of
business, along with increasing regulations requiring businesses to store
documents for any number of years, means fixed content can quickly become an
800-pound gorilla on the back of a company"s storage budget.

CAS: A New Storage Category

When organizations have looked for fixed content storage solutions they"ve
faced a multi-faceted dilemma: what they need versus what the storage industry
could provide. The decision of choosing a solution was further complicated by
the judgment of an information"s value (valued in terms of its cost) compared to
the frequency of that information’s use. For example, the frequency of
accessing information such as check images, contracts, or e-mail usually
diminishes as it ages. However, when the information is needed, the speed of
access can be the defining factor in an organization"s ability to take full
advantage of the business opportunity presented. Until CAS, organizations had to
make a hard choice between the speed of information access (provided by magnetic
disk storage solutions) and assured content authenticity (provided by optical
technology). Tape technology, another choice for some, has been ranked as the
least functional/least cost option.

CAS is a new category of storage. It provides the online performance of a
magnetic disk (because it is magnetic disk) and assures content authenticity
equal to or better than optical technology, at a total cost of ownership equal
to or better than a tape library. It offers more functionality for less cost.
CAS provices everything that is needed and wanted for fixed content in one
solution versus today"s scenario of cobbling together dissimilar technologies.
With CAS, an organization"s fixed content is cost effectively available online,
24/7, with assured authenticity.

Optimum Storage and Authenticity

A stark example of how unmanaged fixed content can savage an intelligent
storage network"s resources can be seen with e-mail. If a CEO sends a
company-wide e-mail to 60,000 employees about new travel guidelines, it is
likely to be indefinitely stored on and routinely viewed from a server or a PC
drive. As a matter of convenience, employees may save the e-mail for reference.
For storage administrators, that e-mail message is now taking up 59,000-times
more disk space than necessary. And, because everyone is referring to a copy of
the original message, the risk increases that the content could be tampered with
and forwarded on.

With CAS, instead of sending out thousands of e-mails, an original document
can be created and stored in the CAS repository. Next, this email can receive
digital ‘claim checks’ so that pointers or links can be sent to direct only
authorized employees to the original. Here, the increased efficiency of storage
in a CAS-enabled environment becomes evident and the storage resources,
optimized by CAS, become even greater when a relatively small-sized e-mail is
replaced by a large multimedia corporate-sales presentation stored and recalled
nearly everyday.

Stringent Regulatory Requirements

Take this model of CAS efficiency and apply it to securities documents and
medical records. Here, the business role of CAS in ensuring the retention,
preservation, and authentication of data in a federally regulated environment
becomes even more pertinent. The number and types of federal regulations
governing business records and other data are on the rise. And whether it is the
amended Securities and Exchange Commission Act of 1934, Rule 17a-4, which
requires investment records to be retained for anywhere from five to seven
years, the Health Insurance Portability and Accountability Act (HIPAA) which
addresses the storage and security of health information, or a modern matter of
national security–companies that cannot produce an unmodified original
document can face expensive, possibly catastrophic legal action.

On the technology front, advances in disk drives have fostered the role of
CAS within businesses. Companies that once stored digitally archived records on
tape libraries or older WORM (write-once-read-many) optical drives can now take
advantage of cutting-edge ATA in CAS arrays. CAS uses ATA-disk technology but
that is where comparisons with conventional ATA disk array ends. The features of
CAS"s extensive software layer fortify the business advantages of CAS by adding
peace of mind when it comes to preserving fixed content that absolutely must not
be corrupted. Just imagine pulling up a digitally archived MRI for use as
defense evidence in a medical malpractice suit, then suddenly discovering that
the data has been degraded to the point where a dark spot has appeared on the
body image that wasn"t there before.

Breaking Away from Conventional Thinking

When the reputation and future of a business is on the line, simply focusing
on speed and initial acquisition price of a storage technology is not the
answer. Major corporate players, who understand this, are investing in CAS now
and realizing that CAS pays dividends in three very significant ways.

First, by optimizing storage capacity and streamlining data retrieval through
object-based storage, not complex logical-volume file systems; second, by
ensuring retention, preservation, and authentication of data; and third, by
integrating seamlessly and easily into a company"s existing storage area network
(SAN) and network attached storage (NAS) architectures.

CAS breaks away from conventional thinking about storage by offering all
three of these benefits, and more, in what is perhaps one of the simplest
storage architectures ever designed. CAS arrays attach directly to a company"s
IP-based Ethernet, so no changes are required to existing SAN and NAS designs to
accommodate a CAS array. By operating independently from its place on the
Ethernet, a CAS array can serve files to authorized clients without complicating
the software-based management of other storage arrays. CAS arrays manage the
allocation and location of stored object files internally as a self-managed
process.

This further simplifies the storage administrator"s task by eliminating the
need for complex storage application integration while simultaneously providing
a secure, autonomous, and scaleable reciprocal for fixed content within the
overall storage network–each a money-saving proposition. CAS ‘claim checks’
are digital fingerprints derived uniquely from the object itself to create a
distinct ‘content address.’ This one-of-a-kind content address, along with
the fact that fixed content is stored as an object file, means users are
retrieving the actual original document as it was first placed on the CAS.

Simplified Management

Keeping fixed content in-step with related applications is done using a
technology called content descriptor file, which contains time-stamp
information, application-specific meta data, and the content address of the
fixed content. These CAS-technology features simplify CAS management so that
storage administrators do not have to worry about file system hierarchies which
can drain performance when extended beyond set boundaries. It also enables the
application of specific policies regarding how long certain fixed content should
be saved and when it should be deleted. This reduces the management burden for
storage administrators by way of intelligent automation.

Many types of data that fall under the definition of fixed content are
sensitive in nature, such as medical images, patient records, financial
information. This often moves the requirements for confidentiality and security
to the forefront. The good news is that CAS arrays are virtually unhackable.
With CAS, authorization is maintained at the claim-check level and the system"s
way of relating fixed content to its user application adds an extra layer of
security above and beyond the access codes and passwords. Advanced CAS arrays
can deny user access by the very application being used to call up the fixed
content. With this ability, certain content stored on a CAS arrays can be used
exclusively by departments running their own applications, while the CAS array
continues to serve content to other departments and the World Wide Web as a
whole.

Manoj Chugh president, EMC (India and
Saarc)