Hybrid Cloud and Weblogic WAN Clustering
The whole concept of the "Hybrid cloud" is that the Enterprise maintains some instances of the server running the application on-premise while the scalable instances are available on the cloud on virtual machines.
The obvious benefits of the above approach are similar to the benefits of a full fledged cloud implementation-
1. Pay for what you consume
2. Get scalability - both upwards and downwards without huge investment in infrastructure.
But in addition to these points, the key benefits of the Hybrid cloud are -
1. Maintain control on your existing application and data. No need for expensive re-engineering or moving the entire application to the cloud.
2. Reduce dependence on cloud service provider as both application and data continue to exist within the Enterprise.
But the Hybrid Cloud solution does come with its share of challenges.
1. Security - Transactions are still being processed outside the Enterprise, so adequate care has to be taken to address security concerns
2. Management- Because the cloud provider may not know much about the application that the enterprise is hosting, application management will require close co-ordination as well as more enterprise access for the cloud instances to resolve issues.
3. Responsibilities - because the application is owned and managed by the Enterprise with the cloud provider only providing the infrastructure, clear identification of responsibilities for issue resolution need to be arrived at.
4. SLAs need to be clearly articulated
From a technology perspective Oracle Weblogic Server - WAN clustering seems to be an ideal fit for the Hybrid cluster. This technology supports clustering and asynchronous session replication across 1000s of miles. It is a robust solution and already widely used in the Industry. Instead of using this technology to build a cluster between two data centers of the enterprise, this same technology can be used to cluster the enterprise data center with cloud instances.
The key application of the Hybrid cloud according to me will be for seasonal applications e.g. Travel booking web sites, Retail web sites, University websites are some of the applications which require peak computing power only during some specific times of the year. The Hybrid cloud allows these Enerprises to maintain control on their applications as well as allow them to scale during these peak times.


