Kenexa, a global provider of talent-hiring and-retention services and software, had a serious customer-satisfaction problem.

"Our Web-based recruiter application worked fine in the [United States], but with each packet taking 200 to 240 milliseconds to get to the Far East and 40 to 100 round trips per Web page, our customers in Japan and China sometimes waited 40 seconds or more to complete a transaction," says Kamal Jain, director of ASP operations. Building a datacenter in Europe or Asia was not an attractive option. "An ASP quickly loses its economies of scale that way."

Instead, Kenexa contracted with Akamai's Web acceleration services, which use a combination of caching, compression, and IP and route optimization to speed Kenexa's dynamic, user-customized content. The result: The time to complete multistep transactions for Asian users has been cut by more than half.

Kenexa's experience reveals the new face of the CDN (content delivery network). During the dot-com boom, CDN providers such as Akamai harnessed their huge network overlay infrastructure to cache and deliver static Web pages to millions of consumers. On today's Web, however, static pages are more the exception than the rule, so CDNs have added compression, traffic shaping, intelligent routing, and network optimization to accelerate everything from software downloads to video streaming, corporate Web applications, b-to-b transactions, and two-way Web 2.0 interactions. "The term 'content delivery network' is really outdated," says Kieran Taylor, Akamai's director of marketing. "Our vision is around accelerating all business online."

Although Akamai is still the 800-pound gorilla in the CDN space, the market has expanded and diversified enough to include a number of other important players, including Limelight Networks, LocalMirror, Mirror Image NaviSite, Netli (recently acquired by Akamai), VitalStream (recently acquired by Internap), and more. Indeed, according to Gartner, the edge hosting market, which consists primarily of CDNs and ADNs (application delivery networks), is on the move, growing in North America by more than a third from 2005 to 2006, from US$353 million to $474 million, and is expected to more than double by 2009.