After spending years and millions of dollars deploying a web-based, mission-critical application, the last thing you want to hear is that the rollout is going poorly due to performance issues. But, as organizations continue to migrate to browser-based deployments, that's often exactly what happens. While users enjoy the virtually ubiquitous access to applications--regardless of location--enabled by browser-based clients, they are dissatisfied with the performance of webbased applications versus their old fat-client counterparts.

Combining reduced performance with an increasingly distributed workforce introduces yet another set of factors that contribute to even more disappointing performance. WAN latency and errors prevent web-based applications from being delivered quickly and often result in congested WAN links. A plethora of network and application issues coalesce into a perfect storm, impeding performance and hampering the usability of multi-million dollar investments. Adding a dose of Web 2.0 technologies to the enterprise application mix (whether as part of an existing packaged application such as Microsoft Outlook Web Access or as a completely new initiative) only exacerbates the decline in performance for remote and mobile users.

If you're worried about the performance of your web applications, you're not alone. According to research by TechWeb Network Research, 75% of IT and applications managers experience anxiety related to application performance and 25% report physical aches and pains along with their unease1. These fears are not ungrounded, as there are a myriad of issues that negatively impact the performance of your applications. Network, client, and data center issues all play a role in how well your web applications perform. An application delivery network can act to alleviate the challenges inherent in delivering web applications over a widely variable network.