A hybrid cloud is an integrated cloud service utilising both private and public clouds to perform distinct functions within the same organisation. All cloud computing services should offer certain efficiencies to differing degrees but public cloud services are likely to be more cost efficient and scalable than private clouds. Therefore, an organisation can maximise their efficiencies by employing public cloud services for all non-sensitive operations, only relying on a private cloud where they require it and ensuring that all of their platforms are seamlessly integrated.
In practice, an enterprise could implement hybrid cloud hosting to host their e-commerce website within a private cloud, where it is secure and scalable, but their brochure site in a public cloud, where it is more cost effective (and security is less of a concern). Alternatively, an Infrastructure as a Service (IaaS) offering, for example, could follow the hybrid cloud model and provide a financial business with storage for client data within a private cloud, but then allow collaboration on project planning documents in the public cloud – where they can be accessed by multiple users from any convenient location.
Hybrid cloud models can be implemented in a number of ways:
1) Separate cloud providers team up to provide both private and public services as an integrated service
2) Individual cloud providers offer a complete hybrid package
3) Organisations who manage their private clouds themselves sign up to a public cloud service which they then integrate into their infrastructure
A hybrid cloud configuration, such as hybrid hosting, can offer its users the following features:
Scalability – whilst private clouds do offer a certain level of scalability depending on their configurations (whether they are hosted internally or externally for example), public cloud services will offer scalability with fewer boundaries because resource is pulled from the larger cloud infrastructure. By moving as many non-sensitive functions as possible to the public cloud it allows an organisation to benefit from public cloud scalability whilst reducing the demands on a private cloud.
Cost efficiencies – again public clouds are likely to offer more significant economies of scale (such as centralised management), and so greater cost efficiencies, than private clouds. Hybrid clouds therefore allow organisations to access these savings for as many business functions as possible whilst still keeping sensitive operations secure.
Security; the private cloud element of the hybrid cloud model not only provides the security where it is needed for sensitive operations but can also satisfy regulatory requirements for data handling and storage where it is applicable
Flexibility; the availability of both secure resource and scalable cost effective public resource can provide organisations with more opportunities to explore different operational avenues.