Demystifying Hybrid Cloud

Mandar Kulkarni

Cloud is all-pervasive. With the advent of cloud services and service providers, different cloud computing models are evolving. While private and public cloud models are commonly used across industries, it is hybrid cloud that is fast gaining prominence given the numerous possibilities it offers.

So what is Hybrid Cloud? Simply put, it is an environment which combines two or more unique computing environments, out of which at least one is a Cloud computing environment. It is the two variables – "computing environment" and "combines" which make Hybrid Cloud very interesting. 

Let’s explore few popular combinations of "environments" in Hybrid Clouds:

Physical environment and Public Cloud: This is a gateway to cloud for traditional enterprises by providing a way to leverage their existing environments and by addressing their security and functionality concerns regarding core applications. For example, a bank keeping core banking environment on legacy RISC based machines, while web servers, messaging & collaboration applications and other workloads running on public cloud. This configuration also allows customers to extend their corporate IT security and governance framework to the new public cloud workloads as well This type of cloud allows enterprises to begin their cloud journey without touching legacy applications. Private Cloud and Public Cloud: Organizations which have already begun their cloud journey using private cloud can take the next step by connecting / extending their private cloud environment to public cloud. Suited for enterprises with existing investments in IT Infrastructure who want to start getting Public Cloud benefits like pay-per-use, quick scalability and more. This helps organizations improve the cost and delivery time using public cloud. It also helps handle periodic / unpredictable workload changes.

Physical environment and Private Cloud: Typically used by Government departments with strict security regulations such as defence where no data can be hosted outside the organization’s perimeter. Second use case is traditional enterprises with no cloud adoption. This deployment many times becomes a precursor of exploring public cloud option.

Though this is a less than optimal scenario, few highly regulated verticals see these kind of configurations. They benefit from resource optimization and automation of private cloud by moving all their cloud ready workloads to it. Some of the legacy applications remain physical, but more and more workloads, especially as these organizations embark on application refresh cycle, move on to cloud. This also sets them up for possible public cloud adoption in future.

Public Cloud and Public Cloud: Typically used by Born-in-Cloud SaaS / ecommerce / media / gaming companies. They build their application stack combining many available cloud based solutions -- IaaS / PaaS / SaaS -- mainly from single cloud service provider, but in many cases they use different services from different cloud service providers as well.

These organizations are heavy users of cloud. They build their entire IT delivery using cloud ecosystem.  This gives them required flexibility and agility to scale up and down as per demand and also create a model of payment for IT services, directly linked with revenue. Private Cloud and Private Cloud: This is more of extended enterprise IT architecture where two or more "separate" private clouds are connected. Ideally, multiple virtualization technologies should be brought under one cloud management system to enable optimal use of IT resources, but sometimes cases like mergers & acquisitions, completely disconnected IT teams (across departments or group companies or geographies), etc. result in these kind of configurations.

There are limited befits of this kind of configuration. By connecting two different private cloud IT automation – monitoring, capacity planning, deployment is enhanced. This approach is generally taken as an intermediate step before moving to single cloud management after a merger or integration of two functions. But to really exploit full benefits of private cloud a single unified cloud management is recommended.

Connected to Each Other

For an environment to be classified as true Hybrid Cloud, it needs to pass few criterions of connectivity. Following is the high level overview of them:

Permanent Secure Connection: This is a minimum requirement. For two environments to be classified as hybrid cloud, they need to be connected over a network providing a permanent and secure connectivity – application connectivity, data transfer and management.

Movement of Workloads: One of the key drivers for hybrid cloud is movement of workloads. You should be able to move workloads between your two environments – from one cloud to another and vice versa. There are multiple ways to do this and there are multiple use cases where this could be extremely useful – cloud-bursting, dev/QA to production movement and quick creation of testing environment using production templates. Single Management Overlay: For an environment to be truly hybrid cloud, you need single monitoring and management overlay giving you view and control of your IT environment spread across clouds – monitoring, management, provisioning, workflow automation, movement of workloads and capacity planning.

With many flavours and flexibility of hybrid cloud, it is well and truly on the way to becoming a mainstream architecture of future IT environments.

(The author is Director, Cloud and Datacenter Programs, Microsoft India)