How much performance value do ADCs/load balancers actually provide in the real world?

In his latest blog entry, Strangeloop president Joshua Bixby tested the websites belonging to the top 10 application delivery controller (ADC) vendors - as well as the websites of their case study clients - to find out if ADCs actually provide site acceleration value:

In the past, I’ve singled out CDNS as targets for discussing what performance value they provide. But when I talk to companies about web performance, they don’t just talk about what their CDN is doing for them: they talk up their ADC, too.

To clarify: ADC (aka application delivery controller) is a blanket term coined by Gartner to include the entire family of load balancing products and services. Companies use ADCs for several reasons: scale, security, availability. In recent years, with the emergence of site speed as a priority, ADC providers have begun to tout the performance gains they provide.

There’s no doubt that ADC providers offer value in scale, security and availability. But it recently struck me that no one has taken a close look at how well ADC players actually deliver web performance. Today is a good day to start.

The Gartner Magic Quadrant for ADCs is coming out shortly. In honour of that prestigious list, let’s take the ten companies from last year’s list — along with their own featured ADC case studies, taken straight from their sites — and see how they stack up.

See the results, along with Joshua's conclusions, at Web Performance Today.