Service providers are experimenting with a new approach to geographically distributed storage for disaster recovery...
with the launch of the Distributed Storage Network (dsNet), also called the Storage Internet.
Distributed Storage Network is based on products from Cleversafe Inc., which also runs an open source development project. Cleversafe's information-dispersal algorithm makes "slices" of data that contain added code that scrambles the data for encryption and allows the data to be rebuilt even if some nodes are lost. Cleversafe CEO Chris Gladwin likens it to geographically dispersed RAID with built-in encryption that works over a commodity Internet connection. The Internet label comes from its similarities with IP network peering in the Web world.
Cleversafe has rolled out its dsNet to five service providers in the Chicago metro area, with Cleversafe engineers in charge of the management node. Gladwin said he also plans to sell to large enterprises looking to host and manage their own dispersed storage network and eventually turn over all dsNet management to service providers.
Distributed Storage Network has three hardware components – the Accesser, the Slicestor and a Manager node. The Accesser provides an on-ramp to the cloud by slicing data before sending it over the wire. Customers of a hosted storage provider host the Accesser on their end of the wire, while the service provider hosts the Slicestor. Manager nodes sit out-of-band to monitor and report on Accessers and Slicestors.
For now, total capacity available on the system is 48 TB, and half of that is used by Cleversafe for ongoing tests.
So far, the results of this first attempt to commercialize Cleversafe's vision have been a mixed bag, according to partners. FastRoot, which hosts data centers for software companies, has signed up a dozen end users for disaster recovery using Cleversafe, according to its CEO Terry Howerton.
"The cloud today is not really ready to host enterprise applications," Howerton said, citing recent outages in large-scale SaaS environments hosting single copies of users' data, such as Amazon. "This is more of a hybrid approach, with some local hardware, as well as cloud services, and the distribution of the data means that if one data center location is down, users can still access their information."
But another partner, onShore Networks, which serves primarily small and medium-sized business (SMB) customers, has no takers for the service so far. "SaaS is difficult for small companies because you need a really big pipe to another location," whether it's a service provider or a secondary data center, according to onShore president Stelios Valavanis. Cleversafe mitigates that issue because it doesn't require the full throughput of a fat pipe to one location all the time, "but there are still a limited number of customers who are going to use SaaS, mostly because of bandwidth limitations," Valavanis said.
Valavanis hopes Cleversafe will add a software-only initiator that users can run on existing servers, rather than requiring the Accesser gateway. A software initiator would lower the cost of the service and make it more flexible.
Because dsNet's reliability theoretically increases with more storage hosting sites, Howerton anticipates an expansion of the partner network. "This will also bring costs down, while the speed [of the system] will increase," he said.