Cloud computing involves both the architecture of an application (i.e. the way it is designed and the intent behind its design) and the platform on which the application is deployed. Cloud computing is a way to build, deploy and manage applications using Internet-based server infrastructure. It dovetails well with Service oriented Architecture (SoA) in that applications in a cloud are typically developed in a distributed manner with all the application pieces communicating over the Internet.

Cloud offerings differ from different vendors, but, for example, Amazon offers:

• Computing capacity – Elastic Compute Cloud or EC2 is a Linux hosting capability
• Structured data storage – SimpleDB is a web service-based capability for accessing structured data
• Large data storage – Simple Storage Service or S3 is a web service-based capability for storing and retrieving chunks of data
• Queuing service – Simple Queue Service or SQS is a hosted queue for storing messages to support asynchronous message processing

The cloud is promising to companies of all sizes, but is most powerful for small to mid-sized companies that do not have the money, staff or IT infrastructure to support an on-site enterprise data center. Getting a server to be visible on the Internet is easy. But building the technology infrastructure and staff to support a truly 24×7 data center environment with proper redundancy (both from a hardware, software and networking perspective), backup mechanism and physical & software security is not easy. Especially if this environment has to handle heavy peak loads.

The Benefits
Cloud computing offers many benefits:

• Ability to handle increased capacity and expand capacity and capability without any large upfront investment
• Ability to pay for infrastructure much like you pay for your utilities at home. You pay for what you use and you can configure your application to handle peak load without paying for a massive hardware infrastructure.
• Possibility of reducing IT operations staff

The cloud lowers the bar (from a cost and complexity perspective) to entry for mission-critical, enterprise infrastructure and provides easy access to additional capacity as needed. However, not every vendor’s solution is created equal. To get the most out of certain cloud offerings, it may require modifications or rewrites to existing applications.

The Risks
Probably the largest concern surrounding the adoption of cloud computing is lack of trust (by some) in the security surrounding their data on the cloud. The fear of their enterprise data being compromised is a large concern and a barrier to entry for some companies.

However, despite what some folks may believe, most of the large cloud vendors have much more security talent than the typical corporation. And it is absolutely critical for the survival of any cloud vendor to keep their environment as safe as possible.

The second risk is the fear of an outages at the cloud provider. Could this happen? It did happen earlier in 2008 when Amazon had a service outage and applications were not available. Due to these risks, some companies are planning to wait and see how reliable and safe these services are before jumping on board.

The Players
There are a few of big players (Microsoft recently announced their entrance into this market in 2009) and many small startups in the cloud computing space. Most organizations are selecting to work with the big players due to the potential risk involved in outsourcing their application and data to a small unknown vendor. But the smaller companies seem to be pushing the innovation and providing unique offerings.