Cloud computing providers offer plenty of guarantees about uptime and redundancy, but they are often silent or
vague about service-level agreements (SLAs) for application performance. They are silent with good reason -- they don't control the Internet. But wide area network (WAN) managers must support and improve application performance for cloud-based applications or things could get ugly.
"If IT departments aren't ready and don't ready themselves to measure that performance or optimize that performance [of cloud-based applications], you could have a mutiny. You'll have CIOs getting fired all over the place," said Eugene Alfaro, manager of global IT operations and support at Simpson Manufacturing Co., a global building products manufacturer based in Pleasanton, Calif.
Part of the problem, according to Alfaro, is that enterprise cloud computing has received so much hype that users -- especially those executives who approved financing for the service -- have unrealistic expectations for application performance.
"Performance is a factor of the system's real speed and the user's expectation," Alfaro said. "I drive a Chrysler 300, and if it meets my expectations on the pickup, I'm satisfied. If I get into a Maserati and it has the same pickup as my Chrysler, I'm not going to be satisfied."
Users assume that a cloud-based application is a Maserati, not understanding or caring that Internet performance is unpredictable and outside the control of both enterprises and cloud providers. A poorly written application that performed well out of a data center may crash and burn in the cloud.
Moving to the cloud requires application performance metrics
No single entity controls the Internet -- least of all enterprise IT -- which makes application performance over the cloud something of a gamble. Cloud providers can only make guarantees about uptime and performance within their data centers, according to Eric Siegel -- research director at Burton Group, a division of Gartner Inc. -- who recently published the research note "Managing Network Performance of Cloud-Based Applications."
Once the application leaves the cloud provider's data center, Siegel said, any number of factors can affect its performance. With limited visibility into the Internet, WAN pros might be dealing with a problem in the application itself, users' connectivity, the cloud provider's connectivity or peering points between service providers.
Whatever the cause, users will blame the WAN. Just as WAN pros need to improve application performance from headquarters to branch, they will have to sustain it from the cloud to the desktop, Siegel said.
"Everyone is all consumed with the [cloud computing] security issue, but [application performance] is another issue, too," he said. "You … have to be able to handle incoming complaints. Moving to the cloud [doesn't] somehow absolve you of the need to triage problems."
The performance side [of cloud computing] is a concern -- a big concern -- but the concern depends entirely on the application.
Eugene Alfaro, Manager of Global IT Operations and Support
Simpson Manufacturing Co.
Before inking any deals with cloud providers, networking pros must at least baseline some application performance metrics over the WAN internally, Siegel said. The findings help gauge user expectations for application performance and can be used as a point of comparison when trialing cloud computing services, he said.
"You don't want to drive your whole staff crazy because some bozo in San Carlos can't get his [home] Internet working," he said. "If you've got the measurements, in a minute you've got it handled. If you don't have the measurements, you don't know -- is this the nose of the camel under the tent? Are there 300 pissed-off people who haven't called in yet?"
Starting late last year, Alfaro decided to move Simpson Manufacturing's nightly backups to the cloud. A few months later, the company's finance department received IT's blessing to have its payroll application moved to the cloud as well. Both migrations has caused few application performance hiccups, he said. Despite some concerns about a loss of advanced features, Alfaro is evaluating cloud-based email services for his next move.
He isn't tempted to move his virtual desktop infrastructure (VDI) -- utilized by 95% of the company's 3,000 users -- out of his data centers and into the cloud because the performance hit would be totally unacceptable.
"The performance side is a concern -- a big concern -- but the concern depends entirely on the application," Alfaro said. "Once you're using a [virtual] desktop and your connection starts to slow down, you freak out. You're trying to type but you get two to three pauses, then suddenly four lines appear at once on the screen. Now imagine two to three pauses 10 times throughout the day [due to Internet congestion]. They would go crazy. They would throw their laptops out the windows and fire IT."
Can WAN optimization improve application performance in the cloud?
Alfaro uses Riverbed Technology's Steelhead WAN optimization appliance to improve virtual desktop performance to remote sites throughout Europe, Asia and Australia. But without being able to deploy an appliance in a cloud provider's data center or even monitor application performance, "interactive computing" over the Internet would make virtual desktops unusable, he said.
Although some cloud providers sell private connections into their data centers, Alfaro said he would rather see them offer virtualized WAN optimization as a bundled service with subscriptions, adding that it's also up to WAN optimization vendors to make their virtualized products smarter.
Application-aware appliances could recognize and intercept virtual desktop traffic, such as keystrokes or mouse movements, and display it back to the user before it makes a roundtrip to and from the cloud-based VDI server.
"Connectivity is not going to be the answer. It's going to be intelligent optimization devices," Alfaro said. "What if the WAN optimization systems could fool you to think what you're doing on your local system is happening in the cloud? That level of intelligent WAN optimization for me would be golden."
But application performance is not the biggest concern for some WAN pros who are moving to the cloud. Cost and security weighs heavily on the mind of Michael Shisko, director of IT for Hitachi Consulting, the Dallas-based consulting arm of Japanese tech conglomerate Hitachi Ltd.
Shisko deployed Blue Coat Systems' ProxySG appliance primarily to accelerate internal applications over the WAN. Although he had few expectations for his cloud-based applications, Shisko said he has seen it improve application performance for Microsoft SharePoint and his expense management system.
The ability to sustain or improve application performance in the cloud is still a "top five" concern, he said.
"[Application performance] is an issue. I wouldn't go as far as to say it's a concern, but it's one of those things [we consider] as we talk about what might go in the cloud or what might not go in the cloud," Shisko said. "While IT might understand, it's not always appropriate to say to our end users, 'Well, that's the Internet and there's only so much we can do to control it.' Our users don’t care. They just want it to work better."
Let us know what you think about the story; email: Jessica Scarpati, News Writer.