Establishing a set of reliable metrics for measuring the performance of your web site in the real world is a key success factor. In the next few articles, we will explore what can be measured, how to do it, and how to turn that data into some useful intelligence for your business.

Web site metrics can be roughly classed into three categories: performance measures, popularity measures and e-business measures. Today we will examine the first category _ performance measures.

Performance measurement is all about how well your code and hosting setup perform in actual use. Responsiveness and reliability are your goals and achieving those goals will require management of three key variables: the code set, the hardware, and the bandwidth.

In order to assess whether you’ve put together the optimal combination of the three factors, you will need benchmarks and objective indicators of the sites performance. Key indicators include:

• system uptime
• server response times
• page download speeds
• server errors
• failed hits
• form failures
• effective bandwidth per user

The technophiles will wax rhapsodical about terms like throughput and latency, and certainly they are key technical indicators, but from a management perspective, the metrics are more understandable when expressed in the terms given above. That is, when expressed in terms that relate to the actual end-user experience.

Important sources of data include your Web Trends reports (or other log files), Web Check, server stress tests, and third-party services like Keynote. Server log files give you insight into server errors, form performance and the like, but will tell you nothing about download speeds, uptime, or effective bandwidth.

The industry standard for log file analysis is Web Trends (www.netiq.com/webtrends/). The Web Trends products take your log file data, organise it into useful categories, and display it in graphical formats that can be interpreted by laypeople. To get Web Trends, contact your web host, as they likely offer the service for a monthly fee. It is very affordable _ I have seen it offered for as little as US$2 per month.

Alternatively, if you own your own server, you will need to purchase a license or subscribe to Web Trends’ web-based service.

For more technical statistics, you will have to seek out the assistance of someone with the IT skills to run the tests and interpret the results. The WebCheck system is offered by CompuWare (www.compuware.com) and is a good benchmarking tool for checking a variety of data relating to the integrity of your site. It will help identify slow pages and errors in your link structures. The reports also give basic recommendations for handling problems.

CompuWare licenses aren’t cheap and as a result few firms outside of the IT arena maintain them. Try contacting your IT vendor about WebCheck, as they are likely have a licence for testing purposes.

Web server stress testing tools are another invaluable aid to measuring your performance. A server stress test will simulate loads on your server and provide analysis of effective response times, errors, and bandwidth per user. These tools tend to be quite technical but are excellent for assessing the robustness and scalability of your site. If you are planning a promotional campaign or a web-based event, a server stress tool allows you to simulate in advance load scenarios in order that you may determine whether your site is up to the job.

This year’s Superbowl provided a great lesson on the necessity of projecting loads and testing server capacity in advance of major events. Cadillac, Philip Morris and Universal Pictures were among the 17 advertisers who premiered new ads during the SuperBowl. Unfortunately for the companies, their commercials were too successful _ traffic to their web sites jumped dramatically after the commercials aired and their sites slowed to a crawl, becoming basically unavailable for the duration of the game.

In contrast, Sony, McDonalds and Levi Strauss all anticipated the load spikes and their sites remained accessible throughout the game. No executive ever wants to hear the phrase “your site’s down again,” so test it before the game!

A number of firms specialise in providing independent testing results for sites. Perhaps the best known is Keynote. The company has a large network of testing facilities globally and as a result they are able to produce snapshots of site performance and send you alerts when performance levels fall below a certain point. For a quick look at the metrics, try this link to Keynote indices:www.keynote.com/solutions/solutionspmperformanceindicestpl.html.

In the next Article I will expand on this topic as we delve further into measuring success online.

• view Part 2 of this story