Cloud computing today has moved on from being a buzzword to becoming a reality for organizations across the globe. Depending on the one that suits their business requirements, companies have adopted cloud computing through either the private or the public cloud model.
However neither a public cloud nor a private cloud is a one-stop solution to all IT-related woes of an organization. While a public cloud model is best suited for use by specific types of organizations or business needs, it may not be ideal for use by others. For instance, while a financial services organization can have a CRM application being delivered as a service, it cannot put its critical financing service applications on the public cloud. While cloud providers have worked with IT security solution providers to make both public and private clouds more secure, reasons such as availability and uptime requirements, latency, and compliance and regulatory requirements compel organizations to host these applications on the internal private cloud.
This has led to the rise of a third model of cloud service deliverythe hybrid cloud or the Your Cloud. A hybrid cloud is a combination of 2 or more interoperable clouds that enables portability of data and applications, as well as the flexibility to leverage public and private resources, plus services, all according to the business requirements of an organization and the performance and security needs of an application.
Organizations typically adopt hybrid cloud when they want to take advantage of the flexible, pay-as-you-go abilities that a cloud service provides while having an assurance of the security and the SLAs tied to its critical applications.
A hybrid cloud is a good solution when an organization has applications that have stringent service levels in terms of data confidentiality, uptime, availability, and latency. These applications would need to remain internal and cannot be run from a shared infrastructure, which is one of the attributes of a public cloud. It can choose to continue to deliver these applications from within an internal virtualized infrastructure, while other non-critical applications could be delivered as a service.
For instance, an organization having already invested in storage capacities can look at the public cloud for storage requirements such as data backup. Internal storage thereafter can be used for addressing dynamic storage requirements that is required frequently. Also it prevents the organization from investing in additional over-provisioned storage resources. All future data backup requirements can be addressed from the cloud storage as the demand increases.
While critical applications stay secure within the company firewall, access to periphery applications can be provided as a service. When applications are delivered as a service installation, application management and licensing overheads involved in delivering the applications are eliminated through the internal infrastructure. It also reduces underutilization or over-provisioning of hardware, especially for applications with dynamic resource requirements.
Virtualization technologies have matured enough to provide a single view of private cloud and public cloud platforms such that virtual machine requirements beyond the available capacities of a physical machine can be met from the public cloud, while making the entire hybrid cloud infrastructure function like a single IT infrastructure.
Although hybrid cloud offers the best of both the public and private cloud model, it has its own set of challenges that need to be taken into account. Latency can be a major issue with a hybrid cloud infrastructure especially if internal applications interact with those delivered out of the public cloud. A latency issue or outage of a certain application being delivered as a service can affect the response time of an internal application or lead to a degraded performance of the overall IT infrastructure.
Typically, a virtualized infrastructure forms the foundation of a private cloud. In a hybrid cloud, the virtualization platform needs to have the intelligence built-in to integrate and manage the private and public clouds as a single cloud, such that it can offset all additional resource requirements from the private to the public cloud seamlessly, once the private cloud has reached its resource thresholds.
There could be data or application incompatibilities between the private and the public cloud, especially if the 2 infrastructures are running on different virtualization or cloud platforms. For instance, data on the internal cloud may be stored in a certain format, while the public cloud service provider could have its own set of storage rules and formats for storing data on its cloud. Cloud interoperability could therefore be a big challenge.
Technology solution providers have made significant efforts toward providing cloud interoperability to make the cloud work for diverse customer scenarios. Virtualization and cloud vendors are offering APIs that integrate private and public clouds to form tailored hybrid clouds. Therefore, organizations looking to leverage on cloud should look at the hybrid cloud approach since it is tailored to the unique business needs of each enterprise, while leveraging the existing IT resources. Migration to cloud should be an incremental change with business flexibility paired with security.