The cloud is a rapidly expanding IT solution, with many providers offering services, almost all incompatible with each other. They offer different interfaces and produce confusion for the enterprise. We need standards that stimulate open cloud deployments.
Why a Standard?
Standards deliver interoperability, foster innovation and create competition, which results in lower costs and a wider range of vendors and service providers. This allows the enterprise to choose from many vendors, possibly several for an implementation, and to be able to write and change their software easily without requiring vendor-specific training and certification.
Implementations may require vendor-specific APIs. When the vendor changes their API and its operation, then the enterprise and other vendors have to invest in supporting the changes at a cost to them, not the vendor.
An Open Interface Standard for the Cloud
There have been several attempts to produce a single API standard within cloud computing. Some introduce another layer into the system implementation, a concept which has limitations. The goal of the Open Cloud Computing Interface (OCCI) is to address the different aspects and produce consensus for a cloud Application Program Interface (API).
The OCCI is designed to reduce the software overhead and operational management issues. This can help reduce the growth of proprietary APIs. Enterprises could then write and deploy applications that could be transferable from one cloud service to another.
The Open Cloud Computing Interface
The OCCI is a set of open specifications delivered through the Open Grid Forum (OGF). The specifications define how service providers can deliver their computing, data, and network offerings through a standardized API. OCCI builds upon Web fundamentals and produces an extensible model for interacting with "as-a-Service" offerings (CaaS, SaaS, PaaS, and IaaS).
The Open Grid Forum (OGF) is a group of users, developers, and vendors working for the standardization of grid computing. It was formed in 2006 in by combing the Global Grid Forum and the Enterprise Grid Alliance. The OGF models its production of open standards on those of the Internet Engineering Task Force (IETF).
OCCI Status
There is a working group tasked with the production of the OCCI standard. They analyzed the existing cloud APIs and interfaces and then developed real-world implementations and deployments produced with the participation of many contributors. The effort is continuing with extensions to the specification. The group also works on interoperability test suites, very important for proof of operation. Verification mechanisms have been established. They have worked with other standards bodies that are also working on cloud based standards.
The group has produced an architecture for the standard implementation, with three goals:
* The ability of a provider to "Discover" what capabilities are offered by other providers.
* The ability to extend the standard to cover the range of types of cloud services, from IaaS through SaaS.
* The specifications must also be modular. There are three documents: A core model; how this extends to IaaS; and a simple text-based HTTP rendering. These three can be used individually, combined or replaced as required.
The long article, "Toward an Open Cloud" in the IEEE's Internet Computing publication July/August 2012 issue provides a wealth of information about the Open Cloud Computing Interface (OCCI). You can also learn more about the OCCI standard and its status on their site, http://occi-wg.org/.
The OCCI is not the totality of cloud standards. It is only one piece. More will come as cloud computing matures. What we need to watch for is vendors and providers who want to capture as much of the market as possible by delivering desirable capabilities that do not follow the standard, or add extensions that make the standard unattractive to use.
I wrote a blog on cloud interoperability, "The IEEE Gets into Cloud Interoperability" that may also be of interest.
