Distinctions between archive and back-upmay blur but they remain vital components of any storage
strategy.
On the face of it, there seems no reason why your archive data
is not also your short-term back-up in case of emergency. Back-up
and archive fulfil much the same purpose: storing data for later
retrieval, if and when necessary.
Distinction between archive and
back-up
But such a view would be to ignore the subtle complexities of
differing requirements. Archives require fast, fine-grained access,
perhaps to individual files or records, while usually a back-up is
intended to restore entire tranches of business data after a disk
error or business continuity event.
In simple terms, explains Simon Phillips, managing director at
consultancy Phillips Taylor Brown: "Archiving is the storage of old
data, commonly off-site or on a separate server, in an easily
accessible, but not editable format. The purpose of archiving is
most commonly for reasons of compliance or evidencing certain
courses of action throughout the length of a project - hence its
read-only format to protect data integrity."
Yet Phillips says the subtle usage differences between archive
and back-up can cause confusion. "The uptake of archiving has only
really been seen where there is a specific legal requirement, such
as in public sector bodies. However, that said, it will probably
only be approximately three years before archiving becomes a legal
requirement across all business sizes, sectors and functions. The
benefits in dispute settlement, both internal and external, and
showing a chain of causation are too great to ignore," he says.
Hamish Macarthur, CEO of analyst house Macarthur Stroud
International, believes technicians have blurred the distinction
between archive and back-up.
"
The digital community has not been very diligent in considering
just what archive really is. When you are in the back-up
environment, the older tapes are simply called archive tapes. And
this is where you get the confusion," he says.
Retrieval
difficulties
But when back-ups are the sole repository of historical data,
retrieving individual records, e-mails or files has proven
problematic, he says. "Because people have kept these chunks of
data, they believe they can retrieve the information. But it has
not always been the case, because they've been a bit lax in
considering archiving."
And there is a significant handling diversity between types of
data, as Tim Waterton, VP alliances at data archive specialist
Clearpace, explains: "In the case of unstructured data, the mass of
back-up data comprises compressed copies of the original files
which are self contained and have meaning in their own right. If
you keep the last hundred changed versions of a file, you can
pretty much open the last hundred copies of the file. The most
recent copy is the back-up copy while the other ninety-nine are
archive copies."
But for structured data - the most critical business data is
often held in databases - sophisticated back-up software from the
database vendor is required, says Waterton. "This [resulting] file
is not queryable and is therefore totally useless to a user who
wants to extract information, unless it is restored back into the
originating database. This is not an archive as it cannot be
queried to support e-discovery or historical reporting."
So while there might be murmerings that
cloud-archiving could replace a back-up policy for
smaller businesses willing to put their faith in hosted
services, its efficacy rather depends on the type of data to be
stored.
Business process and legal
compliance
Gartner's Rene Millman is cautious about the capabilities of
archiving products. "It's not a young market, but it's still
evolving." Right now most companies are concerned with storing and
retrieving quickly, he explains.
"Companies have to look at what legislation is currently on the
books and what are their own archival needs, and look for the best
archiving solution in that area. You back up what you need to run
your business, and you archive what you don't need on a daily basis
but which you might be required to hold onto for legislation or
regulation," adds Rene Millman.
But as for the future, the distinction between archive and
back-up is likely to blur.
"Customers would be keen to see convergence between back-up and
archive to reduce storage and storage management costs by 'double
bubbling' one copy of the data for both processes. It is feasible
for unstructured data but not for structured data," explains
Waterton.
And Millband adds that there are a number of companies offering
online back-up. "As the cloud becomes more pervasive, smaller
companies will embrace such technologies and perhaps the
terminology of whether is it back-up or archiving will become
redundant. It will all be storage."
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