More recently, however, load balancing to some degree has been morphed into the newer technology category of application delivery controllers (ADCs). Those devices provide load balancing as part of a broader set of features that may include compression, traffic management, network and application protocol optimization and Layer 7 content switching. Secure Sockets Layer offload is generally an ADC function but can also be found in more traditional load balancers.
Heman Tailor, director of IT at SCAinteractive, a company that provides interactive promotions such as customer loyalty programs, cites the additional features as a plus. The company currently uses the Coyote Point E450GX appliance. ( Fortinet acquired Coyote Point Systems earlier this year.) The technology manages the Web server cluster in SCAinteractive's network operations center, which the company uses to run its promotions.
"Using a load balancer is very typical of running a Web cluster - or any other cluster, for that matter," Tailor says. "There are many solutions out there, but what makes it stand out is features such as hardware compression and SSL offloading, and Layer 7 routing and load balancing."
Those features, Taylor says, "reduce the load significantly on our end, along with making the management of the servers behind the clusters much easier."
As for future developments, Tailor points to the incorporation of global load balancing as most server farms add second and third sites to boost reliability.
Load Balancing's Enduring Qualities Work Well for Failover
While load balancers have grown in sophistication as they meld into application delivery controllers, customers continue to cite the old-fashioned virtue of reliability as the important draw. The capability to shift workloads away from oversubscribed servers in a data center or to failover from one server to another remains a core feature.
Now Nerd, based in Beaverton, Ore., deployed Barracuda Networks' Load Balancer 440 to support its NerdDeck offering, a white-label remote technical support service. NerdDeck serves as its customers' remote support department, providing a phone and chat service as well as remote access tools.
Geoff Turner, Now Nerd CEO, says installing the load balancer paid off within weeks of purchasing it. A server failed overnight, but the load balancer detected the outage and redirected requests to other servers. Now Nerd staffers never noticed the problem until they came in the next morning, checked email and discovered the server alerts. Customers detected no change in service.
"Different people have different purposes for load balancing," Turner says. "Our goal was not offloading SSL. It was to give customers a consistent experience."
That said, Turner notes that his company may use some of the newer features such as global load balancing down the road.
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