Just a few years ago, hybrid clouds were seen as mere stepping stones for enterprises on a journey that would ultimately end in the public cloud. But as enterprises put cloud computing to real-world use, some industry observers are beginning to see the hybrid cloud model as the way forward.
Hybrid clouds -- defined as a composition of at least one private cloud and at least one public cloud, ideally connected with software that allows a single point of management -- are one answer to enterprise companies' objections to pure public cloud deployments. They allow for security- or performance-sensitive systems to live behind the corporate firewall while also allowing organizations to take advantage of public cloud's elasticity and quick provisioning.
"It's absolutely a trend," said Carl Brooks, analyst with Boston, Mass.-based 451 Research, predicting that hybrid cloud will be "the dominant way in which enterprises will do infrastructure."
Save money with a hybrid model
Chief among the justifications for the hybrid model is the matter of cost.
First, as enterprises gain more experience running applications in the public cloud, it becomes clear that running relatively static workloads there doesn't actually yield cost savings over on-premises deployments.
For example, a piece of software that costs $120,000 for a perpetual license with 20% maintenance represents a $240,000 expense after five years. An initial deployment on a public cloud that costs half that amount initially -- $60,000 for one year -- will cost a total of $300,000 over a five-year period.
At the same time, not having to pay for infrastructure for temporary or highly variable workloads is a boon for IT pros.
"The public cloud gives you flexibility to not have to purchase hardware when you run into peaks and have it just sit there when the workload hits a valley," said Luca Ranieri, technical architect for Innovapost, which provides IT services to Canada Post and affiliated companies.
"Peaks for most companies are very limited, so you can do burst usage and save on cost. It's mostly a cost game."
Cost is the driver for hybrid cloud at Monsoon Commerce, an e-commerce firm based in Portland, Ore. "A lot of times when there are projects that come from above, they require a lot of infrastructure that we don't have readily available," said Michael Warchut, senior network engineer. "Developers can also prototype something out in [Amazon's Elastic Compute Cloud (EC2)] and if it turns out their idea is not going to work, they can come to that decision before we spend the money internally and build the infrastructure."
Regain control of sensitive workloads
Corporate governance also plays a strong role in the shift toward the hybrid cloud model. Despite the fact that public cloud vendors advertise advanced security credentials and compliance certifications, many enterprises are still reluctant to host sensitive workloads outside the data center.
However, this reluctance has led in some cases to what's known as "shadow IT," in which business units circumvent IT and deploy workloads in the public cloud anyway. IT pros are faced with a choice: get those existing public cloud deployments under IT control or risk security vulnerabilities they're not even aware of. A hybrid cloud approach leaves the business with a kind of middle option where workloads suited to public cloud can remain where they're deployed, but come under IT's purview.
"I think that's where more businesses want to be, saying, 'Let me think about the business risk and rewards of having my workload on a public cloud, and have both public and private cloud available for me to make a decision with,'" said Rod Smith, VP of emerging technologies for IBM.
Other IT organizations opt to go with targeted public cloud deployments of specific applications, while leaving most of their workloads in-house where there is already adequate infrastructure to support them.
Novitas Data, a litigation support vendor based in Portland, Ore., uses SunGard Data Systems Inc.'s SunGard Availability Services to host an e-discovery application by kCura Corp. called Relativity.
"It needs to be able to process and show lots and lots of small files, and it needs to have good performance for our clients," said Alex Wall, director of client services and general counsel for the firm. "That's why we like SunGard … because they sit on the Internet backbone in Philadelphia, and we can serve Boston, New York, Atlanta and Chicago with very low latency and good performance throughout the rest of the country."
Not every application needs that kind of geographic distribution, however. "We're talking about a premium solution for an outsourced infrastructure and Internet," said Wall. "Basically, we don't want to be using that unless we're billing for the space that we're using, which is what we do with Relativity."
BMW AG, headquartered in Munich, Germany, plans to move some high-performance computing (HPC) workloads to a cloud service provider in Iceland whose data center runs on geothermal energy in an effort to cut down the car maker's overall carbon usage.
The HPC app is also suited to public cloud because "often we need additional capacity for special jobs, which we would like to buy instead of getting more capacity installed in our own site," said Mario Mueller, VP of IT infrastructure for the company.
In the meantime, most of BMW's applications run in a custom-built private cloud for security and compliance reasons -- as well as to avoid the threat of public cloud outages.
"A production system running for a plant is not an easy job, and if you have any outage there it's a great big impact to the company," Mueller said.