Fog of definitions hides hybrid cloud's truth

Hybrid cloud seems to be the flavour of the day, but most people fail to realise that it is really all about integration, says Lori MacVittie.

Some people continue to spout about the inexorable migration to public cloud computing, but surveys paint a different picture. So in the absence of mass adoption, the focus has switched to on-premise cloud computing in the belief that a hybrid cloud is the way forward. That shift has in turn started another debate about terminology.

This time it is about 'hybrid' and what that really means. Is it just a description of combining traditional deployment models with a cloud deployment model on-premise?

Does a hybrid cloud require both on-premise and off-premise cloud-deployment models? Just what does it mean to employ a hybrid cloud strategy?

Unproductive definitions
Most experts refuse to discuss the definition of cloud these days because it is unproductive. By and large they are right, because regardless of what any expert claims is or is not cloud computing, organisations are moving ahead with their own implementations.

Organisations have come to understand what many — usually those with a vested interest in narrowing the definition — refuse to acknowledge. Cloud computing is a deployment model, an architecture, an application-delivery model, but it is not a tangible thing that can only exist in specific locations.

Those who have already come to that conclusion are likely to also recognise that hybrid cloud is merely an integration strategy. It is the means by which they can control their applications and infrastructure while taking advantage of public cloud computing resources.

Regardless of whether a hybrid strategy focuses solely on internal deployment or includes external deployment options, the key to hybrid is integration.

Riding the hype wave
Once upon a time, when service-oriented architecture (SOA) and web-oriented architecture (WOA) were riding the hype wave, everyone focused on integration. How do we integrate applications that simply couldn't be webified — mainframe-tethered applications, for example — into our web architecture?

How do we integrate partners' systems with our own to make our supply chain processes more efficient? How do we integrate web services with our own applications?

This same process is occurring now, but at the infrastructure level. Instead of simply integrating applications — something with which IT is well versed these days — we are shifting our focus toward integrating infrastructure — something with which IT is not so well versed.

But like its application predecessors, a successful integration strategy must be able...

...to incorporate on-premise, off-premise and legacy systems to enable consistent processes and management of resources across the entire infrastructure.

Expand local capacity
The scenario in which hybrid is most often mentioned is overflow capacity, cloud-bursting if you will. The gist is that the datacentre is somehow extended to include public cloud compute resources as a means of expanding local capacity. This approach requires integration, and quite a bit of it.

Simply provisioning the resources in a public environment isn't enough. It must be tied back into the infrastructure and the delivery process. It must be joined to the existing resources so that it appears a seamless extension of the corporate compute resource pool. This process requires integration into existing infrastructure architecture.

Whether the resources are local or remote, traditional or cloud, they must work together. And working together in technological terms means integration, and integration requires attention to architecture.

Without an architectural strategy that recognises and addresses the need for integration across disparate datacentre deployment models, it will be difficult for the value of any cloud computing model to be realised.

Exercise in integration
Architecture is founded on integration: "This piece of functionality goes over here, that piece over there, and they work together like so." It doesn't matter whether we're talking about board design or systems.

It's about the way in which the individual pieces of infrastructure are assembled and how they connect to form something greater than the sum of its parts. Without an architecture, without integration, we are missing the real value of cloud computing in any form.

Joe McKendrick noted this fact in his blog entry: "Architecture is the missing ingredient needed to help cloud computing deliver to the business — but to date, cloud architecture has meant building or buying clouds."

Exploiting cloud computing is what hybrid is about, and exploiting cloud computing resources means integration. Integration of resources, of services and of applications.

Whether it is the integration of cloud services with internal traditional infrastructure, or internal traditional infrastructure with internal cloud services, it's still about integration.

Hybrid is an integrated architectural approach that provides the means by which all components — regardless of location or style — can be exploited to provide value to the business and, in the case of cloud computing, to IT as well.

Lori MacVittie is responsible for application services education and evangelism at application delivery firm F5 Networks. Her role includes producing technical materials and participating in community-based forums and industry standards organisations. MacVittie has extensive programming experience as an application architect, as well as in network and systems development and administration.