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The Cloud Offers Promise for Storage Users
December 10, 2008
By   Marty  Foltyn

"Cloud computing"has been ill-defined and over-hyped,yet storage vendors have beenquick to trot out their own "cloudstorage" offerings and end users arewondering whether there's significantcost savings in these servicesfor them, particularly in tough economic times.
"Cloud-speak" can bedownrightconfusing. A recent Storage Networking World conference trackproclaimed thatclouds "are an evolving approach to providing userstransparent IT servicesthrough a shared infrastructure of pools ofsystems and services." Clouds"provide a vision of a frictionlesseconomy enabled by lowering the barrierfor entry and reducing thepenalty for failure." And clouds "are avehicle to deliver infiniteresources, a commitment proportional to need, andcost-effectiveeconomies of scale," albeit with a few caveats onexistinginfrastructure, manageability, and security.
Surprisingly, Gartnerconsiders the amorphousnature of the term to be good news: "The veryconfusion and contradictionthat surrounds the term 'cloud computing'signifies its potential to change thestatus quo in the IT market," theIT research firm saidearlierthis year. Gartner perhaps didn't help matters any by definingcloud computingas a "style of computing where massively scalableIT-related capabilitiesare provided 'as a service' using Internettechnologies to multiple externalcustomers."
John Webster,principal IT advisor atIlluminata, simplifies matters by advisingusers to "think of the cloud asthe Internet," delivering services andcomputing resources.
Oddly enough, storage vendors developed someof the earliest cloud services (see Storage Service Providers Make a Comeback), although ittook another decade for the economics of Internet-based storage to make sense.
"The application'sstorage is whateversits up there on that 'ethereal thing,'" saidWebster. There are differentways to access that storage, whether as anexternal service or setting up yourown "cloud" inside your enterprisefirewall.

'Private' CloudsSajai Krishnan ofParascalelikens such services to renting a car: "Your company needsmore storage,and cloud storage is the vehicle," he said. "You caneither 'rent'cloud storage in an external services public cloud, or'buy' cloud storage as aprivate cloud inside your firewall."
External clouds,provided by services fromcompanies like Amazon (NASDAQ: AMZN), Google(NASDAQ: GOOG) or EMC's (NASDAQ:EMC) Mozy, let companies bring upapplications and access internet storagefairly quickly withoutinvesting any capital. These kinds of cloud servicesoffer advantagesto companies looking to balance the services needed to move thecompanyforward with the need to conserve expenditures.
Security can be anissue for companies sendinginternal data to these outside clouds, somany companies are investigating theconcept of "internal" or "private"clouds based in theInternet or on an internal intranet. These internalclouds can offer theadvantages of specific design and controls, yetoften require more capitalexpenditure for servers and storage. Anumber of companies, however, areemerging with solutions thatcapitalize on the benefits of cloud storage whilemitigating costs.
Parascale, forexample, produces software thatenterprises can use to mix and matchtheir existing server hardware already inthe data center to buildclouds that cluster tens to hundreds of servers. Theseservers act asone giant file repository to meet capacity and parallelthroughputdemands for a variety of applications.
Parascale's approach,according to Krishnan,is to use commodity servers that companies canpurchase or that they alreadyhave in their data center. "We provide away to rack them up together andstretch them using software to providea feeling of a big storage appliance —essentially cloud storage," saidKrishnan. "This easy to self-manageappliance is ultimately a singleresource accessible over some kind of network,whether it be thecorporate intranet or Internet services like Amazon."
The ability torepurpose and reuse assets intimes like these is seen as a primebenefit of private clouds. A good time tolook at building your owncloud is when you have 20 to 30 terabytes of datagrowing at 25 percentto 50 percent a year, suggests Krishnan. Companies candevelop internalclouds that take advantage of servers unused in a closet fromamulti-year refurbishment program, or servers still under warranty thatare yetto be designated within a virtualization initiative.

Security and Compliance IssuesWhile cloudstorage isnot applicable for tier-one, mission-critical data due to the natureofthe information (e-mail, databases, transactional data), private cloudscanserve as community storage pools for enterprise backup and archivaldata. Cloudstorage can also be a viable option for static dataresulting from applicationssuch as digital content and distribution,video surveillance, or streamingmedia.
Internal clouds canalso offer advantages tousers concerned with security issues who aremore comfortable with their staffmanaging data within a corporateintranet than over the Internet.
Especially with new regulations such as theFederal Rules of Civil Procedure (FRCP)on depositions and discovery, using cloud storage in ahighly redundantway helps make sure enough copies are lying around based on apolicyset. It can also free up expensive human resources now targeted tosortingand cataloging data.
Security experts note,however, that forregulated data moving into any kind of a cloud,security best practices in theareas of encryption, key management andgeneral storage security apply. Asoutlined in the SNIA StorageSecurity Best Current Practices Technical Proposal,organizations should"ensure appropriate service-level objectives forvirtual storage: 1) matchthe availability objective for the 'storagecloud' to the applicationrequirements; and 2) match theconfidentiality and privacy requirements for the'storage cloud' to thetypes of information stored."
Companies might also be wise to examine theirstorage and retention procedures in light of tracking down data relevant to an e-discoveryrequest. If organizations are already havingtrouble finding data,cloud computing could potentially create more places onehas to look.And storage on external clouds or third-party facilities could alsobeincluded in any FRCP requests for backups and disaster recovery copies.
Clouds are aneconomically attractive servicemodel, said Webster, who recommendsthat organizations find someone whounderstands their storage andsecurity needs and who can develop solutions toaddress them. Companiesmay choose external cloud services if they can getcomputing servicescheaply, and then evolve to include internal clouds once theyfigureout how to lower infrastructure costs. Remember that cloud storage isnota replacement for current storage implementations, but a storageoption that canoffer additional cost and other benefits.



[ 本帖最后由 henrypan1 于 2008-12-10 19:34 编辑 ]