Application performance-management vendors are dangling a new carrot in front of network executives for aligning IT with business goals: the user experience. As network executives try to ensure critical applications operate at peak performance, a number of vendors promise to deliver the only measurement that matters.

After all, who cares that servers are responding quickly if users complain their applications are slow? And so what if a Web page loads in less than 2 seconds if it delivers the wrong content to the visitor? The user experience - employee or customer - with any given application now is the standard against which an IT department must measure itself.

Client-side performance management and you Before you decide if this level of performance monitoring is right for your enterprise . . .
ASK YOURSELF
•	How many of my applications are so critical to the business that client-side performance problems would impact productivity or revenue?
•	What are my options for integrating new, client-side technologies into my existing infrastructure management tools?
•	How am I planning to measure my most complex applications, such as loosely coupled applications based on Web services and a service-oriented architecture?
•	Do I have access to all the clients necessary to implement agent-based monitoring, or do I need to rely on appliances, probes or other methods?
•	What policies and procedures must I put in place to perform real-time troubleshooting or to take action should the client monitoring tool determine a performance problem?
ASK YOUR VENDORS
•	Do you collect application- performance data from the client perspective by putting agents on user machines, or do you collect by active testing?
•	If you collect data by active testing, does such testing simulate traffic for a baseline reading? If you simulate traffic, how do you ensure that it reflects an accurate user experience?
•	If your product requires distributed agents on client machines, how are they installed, configured and updated? How can this process be automated to minimize manual labor?
•	Do you support mobile or remote workers? How does the product measure performance for users connecting over the WAN? How does it measure performance for users connecting over the Internet?
•	Can you correlate user experience with other performance measures for network and systems management? How can your client-side performance-management tool help me understand what was happening elsewhere in the infrastructure at the time of the poor client experience?
•	Does your client-side product easily integrate with my traditional, server-side application-management tools? Does it integrate with any other network-management tools?

"We wanted something akin to us sitting next to end users as they logged on to our Web site, seeing what they see in terms of performance," says Steve Weiskircher, CIO at Crutchfield.com, a direct integrated marketer in Charlottesville, Va.

"We needed a level of detail beyond, 'There is a performance problem.' We wanted to see the steps that lead up to it, how the application responded at each stage and what the end user experienced with our application."

Weiskircher got the visibility he wanted by deploying TeaLeaf Technology appliances.

Many views on app performance

TeaLeaf is one among many vendors banging the user-experience drum. Others include Citrix (via its Reflectent Software buy), Compuware, Coradiant, NetQoS, PremiTech, ProactiveNet and Symphoniq. Each has its own take on how to collect client-side performance information.

Citrix and PremiTech deliver management software and distributed agents deployed on client machines to capture application performance data. Compuware, ProactiveNet and Symphoniq rely on monitoring software that collects performance metrics across an infrastructure, without requiring agents on every managed client machine. For instance, Compuware's ClientVantage software (which starts at about $31,500) uses agents installed on standard PCs to act as robots that tap into applications and simulate transactions. IT managers locate the robots in various network segments to act as real users.

Coradiant, NetQoS and TeaLeaf use appliances to monitor traffic and capture metrics, such as response time, while users interact with applications. And synthetic Web-application and site-performance measurement tests from Gomez and Keynote Systems use agents distributed throughout the Internet to determine how a Web site and the applications running on it react to peak loads and various geographies.

The tools typically offer their own management interfaces and reporting features, and many vendors partner with companies such as BMC, CA, HP and IBM to deliver the client perspective to larger management consoles. Some IT managers do the integration on their own. For instance, Weiskircher integrates the data collected by TeaLeaf with "raw server metrics" gathered by Microsoft Operations Manager.