A hybrid cloud is a composition of at least one private cloud and at least one public cloud. The private cloud can either be maintained by the user company or a private cloud hosting provider. The public cloud can be any services subscribed from ay of the public cloud vendors like Amazon web services, Rackspace etc. Some use cases include keeping the application servers internally and make use of the storage in the public cloud for archived data. Such hybrid cloud approach offers immediate provisioning and rapid scalability on an as needed basis. Organizations may host critical applications on private clouds and applications with relatively less security concerns on the public cloud. A related term is Cloud Bursting. In Cloud bursting organization use their own computing infrastructure for normal usage, but access the cloud for high/peak load requirements. This ensures that a sudden increase in computing requirement is handled gracefully.
Cloud providers support private clouds now, for example; Virtual Private Cloud from Amazon Web Services. There is also support for establishing VPN connectivity to the private cloud from our company network. So this enables Cloud based hybrid cloud build either within the same provider or cross platform. The hybrid cloud is the best among the three as it brings together the comfort level of a private cloud & the flexibility and versatility of the public cloud. The figure on left side differentiates the Public, Private and Hybrid clouds.
Gartner/IDC survey predicts the following to happen in the cloud in near future.
More than 50 percent of Global 1000 companies will have stored customer-sensitive data in the public cloud by year-end 2016. Under pressure to reduce costs and operate more efficiently, more than 20% of organizations are already selectively storing customer-sensitive data in a hybrid cloud environment, Gartner says.
Some interesting predictions by Forrester follows;