Cloud storage gateways may be on the verge of fading out as a discrete product category, but the functionality they provide should live on for many years, likely in major storage systems.
EMC's purchase of TwinStrata and Microsoft's Azure StorSimple update this month underscore the importance of the capabilities within the gateways, which are alternately known as cloud controllers, cloud-integrated storage, cloud on-ramps, cloud-enabled storage platforms and hybrid cloud storage devices, as well as other terms.
Enterprises want an easy way to upload data to the cloud. Gateway appliances help by managing and moving data between on- and off-site storage and transforming file- or block based interfaces of on-site systems to the RESTful or SOAP-based interfaces used by the object-based systems of major cloud providers such as Amazon and Microsoft. The gateways serve as bridges from the data center to the public cloud, which they generally treat as a storage tier.
Gene Ruth, a research director at Gartner Inc., said he fields questions every day from enterprises that want to extend traditional storage environments into the cloud, especially when they're coping with high-data growth and tiring of the need to purchase additional hardware.
"The gateway is an essential element," Ruth said. "You really can't do it without the gateway unless you're willing to go off and do some development, and in most organizations, that's not their thing. They don't want to develop software to interface with REST APIs. They want a turnkey solution."
Major storage vendors could have eliminated the need for cloud storage gateways, but they had no economic incentive to build the functionality into their SAN and NAS systems. Providing an easy way for customers to offload data to public clouds made little sense for companies getting the bulk of their revenue from on-site storage systems.
Enterprise desire to use public cloud storage drives market
But they may be reaching the point where they can no longer ignore the desire of enterprises to use public cloud storage. EMC acquired TwinStrata this month with plans to embed the technology into its VMAX arrays to enable customers to move infrequently accessed data to public clouds, between private clouds or even within VMAX systems.
Microsoft's motive was different when it acquired StorSimple in October 2012. The StorSimple appliance gives customers an easier way to upload data to Microsoft's Azure public cloud service. The new StorSimple product update -- the first since the Microsoft acquisition -- tightened the integration with Azure.
The gateway vendor lineup also includes Avere, Ctera Networks, Maldivica, Nasuni, Panzura and Riverbed. Some concentrate on file storage, and others support block, while others claim to offer better performance or tout specific advantages. But while they may have similar underlying technology, cloud gateways tend to have different areas of focus.
"The route to market for each of these guys, and the focus on feature and functionality, is so unique to each solution that they almost don't look like apples and apples," said Ashish Nadkarni, a research director in the storage systems and software practice at IDC.
"Ctera's route to market is all about remote office/branch offices and implanting the Ctera device as a personal NAS box. Panzura is all about global collaboration. Riverbed is all about data protection in the cloud. TwinStrata was all about disaster recovery as a service for virtual environments. Nasuni is all about cloud as a service. Avere is all about providing performance functionality but cloud in the backend."
'Not a separate category anymore'
Marc Staimer, president of Dragon Slayer Consulting, said cloud storage gateways essentially have to serve as the main on-premises storage system. If they don't, the customer has the burden of manually migrating data to them.
He said if the cloud gateway is the main storage system, then it needs to compete with major storage systems from vendors such as EMC, IBM and NetApp. The more logical place for the gateway functionality is bundled into the major SAN and NAS systems, where it will ultimately reside, he said.
"It's not a separate category anymore. It's either a feature of a storage system, or it's a feature of a cloud and the cloud vendor is providing an on-ramp," Staimer said. "As a separate market, I'm discounting it."
Other analysts haven't written it off yet. IDC pegged "cloud-enabled storage" at $180 million in 2013 and views the market segment as "transitionary," according to Nadkarni. "Eventually, all the storage players are going to build this functionality into their platforms, and then that will be the death knell for all these cloud [gateway] players," he said.
Industry analysts tend to predict that the cloud storage gateway market will consolidate within two to five years, with the picks of the litter serving as potential acquisition targets for major storage vendors, such as StorSimple and TwinStrata were.
Randy Kerns, a senior strategist at Evaluator Group, said acquisitions are "very much a probability" as the functionality is integrated into traditional storage systems. In the meantime, he thinks the gateway devices will be around for the next three years.
IDC's Nadkarni predicted more of the major storage players could go the "organic route" and build the gateway functionality into their products. He said it can be difficult to take intellectual property from a cloud-enabled storage platform and integrate into a substantially different major storage system.
The industry has yet to satisfy the demand for a turnkey product from a single vendor, leaving customers to deal with multiple vendors when they put together their cloud-integrated storage environments, Gartner's Ruth said. He said all of the large storage vendors eventually should give in to the new cloud storage medium and offer gateway-like functionality.
"Certainly, we have been advising them to get into this market space," Ruth said. "You can't put your head in the sand and hope it goes away. You have to deal with it."
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