Amazon’s S3 REST implementation clearly has buzz amongst early cloud adopters. And now practically every cloud storage vendor has a proprietary REST API implementation. Remember Betamax vs VHS? Here we go again. Read on, for the long version.

         In our conversations with service providers, especially the smaller and mid-sized hosters and MSPs, the question about WAN access via the REST API comes up all the time. Vendors talk about this a whole lot for sure. And surely WAN access to a cloud service is very important.

         First, for those who have not gotten the REST bug - what is REST? The REST API is a relatively recent WAN data-access approach based on the HTTP protocol. Amazon’s S3 has clearly demonstrated its simplicity, power and utility. Simply put, this uses “methods” (like get, put, delete) that are intrinsic to HTTP, and uses some proprietary encodings of strings inside HTTP to enable flexible WAN read-write access to your data.

         There is absolutely no question that a cloud service must provide WAN-friendly access methods (tolerant of WAN latency) whether it is a REST API, FTP or WebDAV protocol. The real rub for service providers is that the last two are long term standards. The first, the REST API, though all the rage now, is emergent and there are no standards. At this point Amazon, EMC, Nirvanix and several other vendors have pushed ahead with their own REST APIs to serve their customers - and an effort to standardize has not made much headway. One REST implementation is not the same as the next because a customer would have to use each vendor’s different API set, code the reads and writes inside their applications, or use tools (an explorer type file access window, backup applications etc. - vendors with proprietary REST APIs get to create and maintain these tools themselves).  From having looked at Amazon’s S3, Rackable’s Cloud Files, Nirvanix, customers are very aware of the lock-in problem and ask about this at the outset. In fact customers are more aware of this issue than some of the smaller and mid-sized MSPs who are rushing to deploy a REST interface, any REST interface, for their storage cloud offering.

         Now about the WebDav standard. WebDAV is a WAN data access protocol that has been around since the late 90s, and there is clearly vendor momentum behind this with support from EMC, IBM, Sun (and ParaScale) to name a few. And there is large set of tools that support it, though it has not garnered the community imagination in the same way as Amazon’s S3 REST implementation. And in addtion, SNIA is working on standardization efforts as well - but first instances of this seems at least a year away.

         So maybe we will end up with 3 relatively standard WAN access options - Amazon’s S3 REST has potential to be one of them, and maybe it will be WebDAV too after all (or not), and maybe in some extended time there will be a SNIA storage industry standard as well. But it is hard to see how another vendor’s proprietary REST API is going to have any longevity. Rackspace’s recent announcement to open source its REST APIs is the right strategy for them and an indication of their recognition of the difficulties of proprietary and proliferating APIs for customers, service providers and vendors. If Rackspace, the #2 cloud player feels this way, it is simply good strategy for new cloud service entrants to pause and reflect on their cloud access choices.

         So MSPs and hosters looking to roll out a new storage cloud offering, with a REST API interface, must ponder if their choice is REST nirvana or REST-IN-PEACE.

Sajai, CEO, ParaScale