Service Orientated Architecture (SOA) and Web 2.0 technologies can help organizations implement Cloud services in their IT environment.
The following diagram shows the layers of an emerging Enterprise Computing Stack.
Web 2.0 allows for building user interfaces and collaboration. Within an organisation this technology is referred to as Enterprise Web 2.0, it can be delivered using enterprise portals such as Microsoft SharePoint, Oracle WebCenter Suite and IBM Websphere Portal.
SOA enables the building and integrating of applications improving business agility. SOA can be used to take advantage of Cloud services and present these resources to the users via Web 2.0 technologies such as AJAX, Mashups, RSS and enterprise social computing. SOA greatly reduces the risks when building Hybrid cloud environments by providing a more integrated on-premise and public cloud solution. SOA also makes it easier to move services between Cloud environments. If an organization doesn’t have an on-premise cloud, having an SOA environment helps to identify and integrate public cloud services into the existing environment.
The three Cloud computing layers shown in the diagram are:
Infrastructure as a Service (IaaS) provides hardware and system software as a service including Storage, Compute and Operating Systems. These services provide access to IT infrastructure components.
Platform as a Service (PaaS) provides services for creating, deploying and managing applications
Software as a Service (SaaS) is application software delivered as a service.
These Cloud layers can be implemented individually, they do not depend on one another. SOA principles can be applied when building the Cloud layers. SOA architectural principles for example can be used to build a service-oriented Infrastructure as a Service (IaaS) layer.