Hybrid Architectures Do Not Require Private Cloud
Oh, it certainly helps, but it’s not a requirement
Taking advantage of cloud-hosted resources does not require forklift re-architecture of the data center. That may sound nearly heretical but that’s the truth, and I’m not talking about just SaaS which, of course, has never required anything more than an Internet connection to “integrate” into the data center.
I’m talking about IaaS and integrating compute and storage resources into the data center, whether it’s cloud-based or traditional or simply highly virtualized.
Extending the traditional data center using hybrid model means being able to incorporate (integrate) cloud-hosted resources as part of the data center. For most organizations this means elasticity – expanding and contracting capacity by adding and removing remote resources to a data center deployed application. Flexibility and cost savings drive this model, and the right model can realize the benefits of cloud without requiring wholesale re-architecture of the data center.
That’s something that ought to please the 50% of organizations that, according to a 2011 CIO survey, are interested in cloud specifically to increase capacity and availability. Bonus: it also serves to address other top drivers identified in the same survey of reducing IT management and maintenance as well as IT infrastructure investment.
Really Big Bonus? Most organizations probably have the means by which they can achieve this today.
LEVERAGING CLOUD RESOURCES FROM A TRADITIONAL DATA CENTER
Scalability requires two things: resources and a means to distribute load across them. In the world of application delivery we call the resources “pools” and the means to distribute them an application delivery controller (load balancing service, if you prefer).
The application delivery tier, where the load balancing service resides topologically in the data center, is responsible for not only distributing load across resources but for being able to mitigate failure without disrupting the application service. That goes for elasticity, too. It should be possible to add and remove (intentionally through provisioning processes or unintentionally through failure) resources from a given pool without disruption the overall application service.
This is the primary business and operational value brought to an organization by load balancing services: non-disruptive (or seamless or transparent if you prefer more positive marketing terminology) elasticity.
Yes, the foundations of cloud have always existed and they’re in most organizations’ data centers today.
Now, it isn’t that hard to imagine how this elasticity can extend to integrate cloud-hosted resources. Such resources are either non-disruptively added to/removed from the load balancing service’s “pool” of resources. The application delivery controller does not care whether the resources in the pool are local or remote, traditional or cloud, physical or virtual. Resources are resources.
So whether the data center is still very traditional (physical-based), has moved into a highly virtualized state, or has gone all the way to cloud is really not relevant to the application delivery service. All resources can be operationally managed consistently by the application delivery controller.
To integrate cloud-based resources into the architecture requires only one thing: connectivity.
The connectivity between a data center and the “cloud” is generally referred to as a cloud bridge (or some variation thereof). This cloud bridge has the responsibility of connecting the two worlds securely and providing a network compatibility layer that “bridges” the two networks, implying a transparency that allows resources in either environment to communicate without concern for the underlying network topology. How this is accomplished varies from solution to solution, and there are emerging “virtual network encapsulation” technologies (think VXLAN and GRE) that are designed to make this process even smoother.
Once a connection is established, and assuming network bridging capabilities, resources provisioned in “the cloud” can be non-disruptively added to the data center-hosted “pools” and from there, load is distributed as per the load balancing service’s configuration for the resource (application, etc… ).
THE ROAD to CLOUD
There seems to be a perception in the market that you aren’t going to get to hybrid cloud until you have private cloud, which may explain the preponderance of survey respondents who are focused on private cloud with must less focus on public cloud. The road to “cloud” doesn’t require that you completely revamp the data center to be cloud-based before you can begin taking advantage of public cloud resources. In fact, a hybrid approach that integrates public cloud into your existing data center provides an opportunity to move steadily in the direction of cloud without being overwhelmed by the transformation that must ultimately occur.
A hybrid traditional-cloud based approach allows the organization to build the skill sets necessary, define the appropriate roles that will be needed, and understand the fundamental differences in operational models required to implement the automation and orchestration that ultimately brings to the table all the benefits of cloud (as opposed to just the cheaper resources).
Cloud is a transformational journey – for both IT and the business – but it’s not one that can be taken overnight. The pressure to “go cloud” is immense, today, but IT still needs the opportunity to evaluate both the data center and cloud environments for appropriateness and to put into place the proper policies and governance structure around the use of cloud resources. A strategy that allows IT to begin taking advantage of cloud resources now without wholesale rip-and-replace of existing technology provides the breathing room IT needs to ensure that the journey to cloud will be a smooth one, where the benefits will be realized without compromising on the operational governance required to assure availability and security of network, data, and application resources.