Analysts predict that the next two years will be big for the hybrid cloud: In a Gigaom survey, 76 percent of IT decision makers indicated that hybrid clouds “will be the core cloud strategy” for their organizations. Likewise, Gartner predicts that nearly half of large enterprises will have hybrid cloud deployments by the end of 2017.
“In the past three years, private cloud computing has moved from an aspiration to a tentative reality for nearly half of large enterprises,” Gartner reports. “Hybrid cloud computing is at the same place today that private cloud was three years ago; as actual deployments are low, but aspirations are high.”
Most people define hybrid cloud as a combination of private and public cloud resources. This can be useful if overload on your private cloud needs to overflow into the public cloud, for instance. It also offers protection and backup for data, as Arthur Cole explained here on IT Business Edge. (For more use cases, check out “Why Hybrid Cloud Continues to Grow: A Look at Real Use-Cases,” at Data Center Knowledge.)
But as IBM’s Claudio Tagliabue points out, that word “combination” hides one of the real deployment challenges: integration.
“To me, hybrid cloud is a combination of private and public cloud, irrespectively from where the infrastructure is hosted. The key here is combination,” Tagliabue, who works as the tech sales lead for Cloud BPM in the UK, writes. “As soon as you start talking about ‘combining’ two things, integration is around the corner.”
Vendors have talked about integrating the hybrid cloud for some time, but what’s predictable is that they’ll really up the sales pitch as more organizations weigh the pros and cons of hybrid cloud.
All of which raises the question: Is integration that different in a hybrid environment than in a public cloud or a private cloud? In a word: Yes.
It’s (Mostly) All About the API
You need to take new considerations into account when integrating a hybrid cloud, according to Eddie Cole, Scribe Software vice president of engineering.
The first major challenges will come down to API limitations, he writes. That shouldn’t surprise anyone, since most of the cloud relies on APIs to deliver functions, data and services. Why are APIs an issue?
First, APIs are often proprietary and there’s no single way to write them, which can cause integration challenges. That’s an issue with public cloud as well, so you can most likely resolve it via a connector from an existing cloud integration vendor.
Second, and more problematic, are the API rate limits. Some API rate limits are defined by the SaaS application through policies and rules, but sometimes, the limit comes in the form of poor performance under load, Cole writes. In one case, you can ask — in the latter, you’ll need to test the API.
Finally, not all APIs support full CRUD (control-read-update-delete) operations, he writes. This can create real problems with data integration.
“In fact, more often than not the API will only expose a subset of the data model you previously had access to from the backend,” he writes. “Even if the API exposes the entity you are looking for and the operation you want, you still need to make sure the entity contains all of the properties you need to integrate.”
Another common problem is that the exposed entity is missing properties available in the application’s user interface, he adds.
“Always be sure to know what data entities are available and what operations you can perform on them before you commit to any hybrid integration project,” he suggests.
Hybrid Brings Architecture Back to the ‘S’ Word
While APIs can be part of the problem with hybrid integration, they also are part of hybrid cloud’s potential, according to Tagliabue.
“We talked about integration with back-end systems, we talked about service exposure, and we talked about functionality variations in services,” Tagliabue writes. “We are really talking about a Service Oriented Architecture (SOA), here. It doesn’t matter if it’s XML-based Web Services or sexy RESTful APIs we are using.”
Of course, integrating hybrid applications only adds to the concern around typical SOA service exposure, he adds. But since hybrid requires you to expose services via RESTful APIs, it’s easy to push some services or capabilities onto the public cloud for business partners or mobile apps.
“It’s a simple idea and can quickly scale: Today, I could call my back-end systems, tomorrow someone else’s back-ends, next week it will be other public cloud Web APIs,” he writes. “Frankly, I think that this model is the future of application development.”
That was said about SOA, and to some extent, we’re seeing that concept still play out.
Loraine Lawson is a veteran technology reporter and blogger. She currently writes the Integration blog for IT Business Edge, which covers all aspects of integration technology, including data governance and best practices. She has also covered IT/Business Alignment and IT Security for IT Business Edge. Before becoming a freelance writer, Lawson worked at TechRepublic as a site editor and writer, covering mobile, IT management, IT security and other technology trends. Previously, she was a webmaster at the Kentucky Transportation Cabinet and a newspaper journalist. Follow Lawson at Google+ and on Twitter.