Close

See How Your Peers Are Moving Forward in the Cloud

New research from CDW can help you build on your success and take the next step.

Dec 23 2010
Networking

Speeding Delivery

Link balancing, caching, SSL offload and other techniques improve application performance over the WAN

The city of Aventura faced a difficult dilemma: Police officers needed faster and more reliable performance for traffic safety and surveillance applications, but increasing bandwidth enough to handle the issue would be a lengthy and costly process.

"Law enforcement has to be able to quickly review traffic videos over the web and then get back on patrol," says Karen Lanke, the Florida city's director of IT. "The longer it takes them to access and use the video application, the less productive they are."

Instead of adding bandwidth, Lanke and her staff implemented Barracuda Link Balancer to give critical applications, such as the surveillance programs, the performance and disaster recovery they require. Link Balancer is one of many application delivery optimization devices available today to help boost reliability and speed application delivery over the Internet from internal data centers, service providers and the cloud.

To ensure better application performance across the network, state and local governments are deploying products as basic as link balancers and load balancers for failover to more advanced application delivery controllers.

Such products differ widely in the features they offer. For example, they can be targeted to handle only physical server load balancing and disaster recovery or the more advanced objectives of SSL offload, virtual server load balancing, caching and compression, says Kevin Tolly, founder of testing and research firm The Tolly Group.

"A decade ago, when these application delivery optimization appliances started appearing, they were not affordable to anyone but large enterprises. Now, there are cost-efficient products for every size organization," he says.

Handling the Load

The city of Aventura uses Link Balancer to combine existing links from multiple Internet service providers -- cable and T-1 -- which alleviates the need to increase the capacity of a single pipe. Barracuda's appliance automatically balances the load between the connections to avoid bottlenecks and downtime in case of a link failure or routine maintenance, or if a natural disaster occurs.

Lanke has been so pleased with the results she's seen from Link Balancer that she is beginning to use it for other city applications such as e-mail. Tolly says this kind of ramping up is a good strategy for state and local governments that need to improve application performance. He is opposed to turning on all the features at once. "If you're running a small city tourism site, you're not going to need to offload SSL functions, whereas if you're handling transactions online for the DMV, you might," he says.

The city of Brenham, Texas, also relies on the Barracuda Link Balancer for link aggregation and load balancing. "We had one major Internet connection and occasionally had some problems," says IT Manager Gary Jeter. "We wanted redundancy."

Jeter and his network manager chose Link Balancer in part because of its cost efficiency. Since deploying the product last summer, the city has added a second Internet connection and plans to add a third in the near future. "It's working great," Jeter says.

Accelerator Adventures

At the Delaware Department of Technology and Information, Chief Operating Officer William Hickox is taking a slow and steady approach to ensure that the state's most critical applications are receiving the priority, bandwidth and performance they need. As manager of the state's education network, he uses Blue Coat ProxySG gateway server appliances with an F5 Big-IP application delivery controller to prioritize Delaware's new online student testing assessment tool. "If a student experiences a 5- to 15-second delay during online testing, that's a problem," he says.

Hickox also uses the tools to throttle students' social media and YouTube usage to make sure it does not impact learning applications or the state's financial and ERP applications. Big-IP's caching mechanism has been helpful in ­making sure there is no excess pulling of static images and data.

30%

Network capacity expansion that the Delaware Department of Technology and Information has avoided thanks to use of application delivery control techniques

Hickox is eager to test-drive Big-IP's virtual appliance to set thresholds for load balancing among virtual servers. For instance, he'd be able to create a rule that would have VMware spin up a new server when the virtual server pool reached 80 percent utilization. Such automation would help during critical times such as elections and corporate tax ­filings, he says.

In Sacramento County, Calif., "application acceleration enables the county to hasten law enforcement's access to mug shots, criminal records, vehicle identification and other time-sensitive data," says senior IT analyst Joshua Voelkert. The county is now transitioning from its end-of-life Cisco Content Services Switches (CSSes) to F5 Big-IP appliances for load-balancing law enforcement applications. The ability to logically separate resources on the appliances using partitions has allowed him to provide increased application performance and reliability over what he was able to provide on the older CSS implementation.

Back in the city of Aventura, Lanke says the move away from distributed applications will eventually lead her to test-drive more sophisticated application delivery optimization techniques such as caching, compression and SSL offload. She anticipates such techniques will help her increase the performance, reliability and availability of the city's growing number of externally hosted, mission-critical applications.

Accelerating at the Right Speed

With so many options for application acceleration available today -- including caching, compression, SSL offload and load balancing -- IT leaders have to be choosy:

  • Prioritize which applications need better performance and disaster recovery. Don't try to do all of them at once, as this could adversely affect your overall network.
  • Examine which features would benefit your applications. For instance, like the city of Aventura, your needs might be met by a simple load balancer versus a high-end appliance with more features to manage.
  • Create a calendar of events across your environment to determine where and when you should focus your application acceleration. For instance, if you run an election site, then you'll want acceleration resources available when citizens go to the polls. At the start of the school year, a student assessment tool might need a performance boost.
  • Make sure your acceleration efforts are working. Don't just set your appliance and forget it. Instead, test the environment and ask users for feedback about performance. You may have to tweak your settings or add another feature, such as SSL offload.
  • Be flexible. As you expand your virtual server environment, turn to the cloud and bring on new users and applications, you might find that you have to expand your application acceleration implementation.
Josh Ritchie