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A number of vendors have emerged that provide a bridge to cloud storage services, as well as extended security, availability and portability to cloud storage service provider offerings.
Every new technology follows a predictable path from drawing boards and beta tests to product hypes and launches. Along the way, users often follow their own inevitable route: becoming enchanted, then unsure and, finally, cynical.
After that, the necessary ecosystems emerge to fill in the technology gaps and ensure that real user requirements are satisfied. Value propositions that solve real-world user pain points emerge, and we slowly start to see adoption. Roughly two years after cloud storage was first floated, that's where we find ourselves.
Most cloud storage service provider solutions on the market today offer basic storage capacity and data protection, such as RAID or remote mirroring, as well as RESTful APIs for porting applications. This is all good. But challenges arise because most applications in today's IT shops do not speak REST (Representational State Transfer) because they require block interfaces such as iSCSI, SCSI or Fibre Channel; or file interfaces such as NFS or CIFS. Every cloud storage vendor has its own RESTful API, but they're proprietary; so once data is stored there, it's difficult (if not impossible) to move it to another service provider. In addition, users are concerned about security, accessibility and availability once data
To address these issues we're seeing a new category of cloud storage ecosystem vendors emerge. These cloud storage enablement vendors should fill the gaps inherent in many cloud storage products.
Cloud storage enablement platforms
We've seen a number of vendors emerge in the past year that not only provide a bridge to cloud storage services but bring extended security, availability and portability to cloud storage service provider offerings. On the surface, much of the messaging sounds very similar, which it should, as they solve similar problems. But putting them all on the same playing field would be like comparing a Data Robotics Drobo FS to a NetApp FAS2000; both are network drives and both store data, but they have very different use cases. On a generic level, enablement platforms offer the following:
Data portability. Cloud storage enablement vendors write to the proprietary cloud storage service provider APIs and act as a translation layer that offers a standards-based interface to the application. Application interfaces don't need to be rewritten if users switch cloud service providers. Some enablement platforms can mirror between cloud storage service providers, offering the ultimate in portability because data can be moved seamlessly by mirroring and then cutting over.
Integration with existing environment. Cloud storage becomes "plug and play" when an enablement vendor is used because the platform presents a standards-based application interface into the IT environment.
Data availability. Enablement vendors bring snapshot capabilities to cloud storage. This ability to snapshot the contents of a cloud data store protects against accidental deletions and software corruption issues that could otherwise render cloud storage risky (at best) or unusable.
Data security. Security continues to be a priority for users considering cloud storage, and security capabilities vary by enablement vendor. At the very least, cloud storage enablement vendors offer encryption and leave the encryption keys in the hands of the subscribers. Users must ensure their enablement platform encrypts data in flight and at rest -- from the time it leaves the data center and throughout the flight path.
Local-like performance. Cloud storage enablement vendors offer caching algorithms that ensure active data is stored locally, mitigating issues with distance from cloud providers. Though cloud storage isn't likely to be in a position to support OLTP applications any time soon, most applications in the data center don't require big iron IOPS and cloud storage could sufficiently meet performance requirements for those.
Data reduction technology. Compression and data deduplication can help reduce the overall amount of data stored, as well as bandwidth requirements and costs.
Cloud storage enablement vendors include Nasuni Corp., which offers a Windows file server product that could be used to store user files or to create an off-site copy of Windows file-based data, among other use cases. TwinStrata Inc. offers a block storage interface to the subscriber that provides an iSCSI interface and could be integrated into a backup or disaster recovery scenario. Both Nasuni and TwinStrata are sold as virtual appliances. Cirtas Systems Inc., still in semi-stealth mode, offers a hardware appliance that acts as a local cloud storage controller, where the target storage sits in the cloud. It also presents an iSCSI interface that could drop into a user environment to support tier 2 applications. Panzura Inc. and StorSimple Inc. have introduced offerings that target Microsoft Exchange and SharePoint, helping users to scale and protect these applications.
Most of these vendors don't compete head to head. It's therefore important to do your homework to understand the use case and application-specific benefits each brings to the table.
Cloud storage may not be a proprietary world forever. The Storage Networking Industry Association (SNIA) has a working committee dedicated to creating the Cloud Data Management Interface (CDMI) standard for communication with and between cloud storage service providers. While this may bring portability to data, it doesn't obviate the need for cloud storage enablement vendors. Users will still need an intelligent layer to mitigate latency and provide availability, security, integration with the existing environment, and the ability to address the other issues raised here. Standards will help with adoption, but enablement vendors bring a standards-based interface to the data center that will give users immediate access to the larger benefits of the potential cost reduction and IT elasticity that cloud storage brings to the table.
BIO: Terri McClure is a storage analyst at Enterprise Strategy Group, Milford, Mass.
This was first published in August 2010