By Ben Rushlo, Director of Consulting Services, Keynote Systems Inc.

It would be great if the performance of your company’s Web site, where your customers are browsing, shopping and spending their money, could rely solely on the expertise of your IT staff.

If that were the case, you could ensure customer shopping satisfaction without assistance by building a feature-rich Web site, maintaining a robust IT infrastructure and implementing an efficient Web load testing strategy to keep your online business humming.

The problem, though, is that many of those cool, customer-friendly features that you offer on your site – like helpful “zoom-in” features, glitzy Adobe Flash components, “help-seal-the-deal” video streams, product reviews and “roll-over” details – are likely being added to your pages through Web-based connections to third-party providers. In other words, the performance and reliability of your online business is out of your direct control. No longer are complex Web sites built just by our own staffs. Today’s class-leading modern sites bring in components from far-off servers maintained by a variety of vendors to essentially create “composite Web” sites for online businesses.

But to your customers, your site brings all these helpful, decision-making features to their Web browsers as though it all comes only from you. So if a page doesn’t load or if performance is slow, you can bet they won’t be blaming any behind-the-scenes third-party providers. Instead, they’ll be blaming you, then rushing off to find a competitors’ site where they can make purchases without such aggravation.

Of course, you don’t want that to happen and you can prevent it. To do that, you need to understand and manage this “composite Web” so that you can gain more overall quality control for your customers. So how do you do that? The best plan is to start with detailed, high-quality Web performance analysis and measurement of your site, along with related performance data for all of the add-in components being served up by other vendors.

The traditional data center analysis tools you already have can’t see what’s happening in your customer’s browser and do not track how your “composite” pages are performing. You need specialized Web tools that analyze your site’s performance out on the Internet, in a real browser, in the same ways that your customers are going to your site and interacting with your rich Web features.

Bringing in a Web browser-based external measurement service will help you better manage your site’s performance, along with that of your third-party vendors. Be sure to choose a performance monitoring solution that tracks the various composite pieces of the pages separately, so you can manage them individually. You can then use that information to tighten your Service Level Agreements (SLAs) with your vendors to ensure that their contributions to your site’s sales success are living up to your customers expectations. If problems are found in the analyses of the site and its composite parts, then you have the critical information at your fingertips to get improvements from your vendors, and are on your way to improving online performance.

Ultimately, this “composite Web” performance data is a hugely helpful new business metric that can keep your customers coming back again and again. And that’s an expense worth investing in.