Netli’s identities Akamai Technologies Inc as its main competitor, but whereas Akamai’s key concept is widely distributed caching and intelligent routing, Netli’s is traffic compression and a rather more modest network of caches.

The new feature, NetliOffload, will enable companies to tap into static file caching in two of Netli’s US data centers when they need extra capacity. These cached files will also be delivered using the NetLightning service, Netli’s flagship offering.

NetLightning is designed to reduce the number of HTTP roundtrips required to deliver a web page to a browser. A typical page may contain 30 elements, each of which is delivered over a separate HTTP connection with its own protocol overhead.

Customers deploy a Netli device at their site that proxies for the browser, downloading all the requested page’s elements on the local network very quickly. This data is then compressed and sent to one of Netli’s edge servers, which decompresses it and sends it to the browser.

Sometimes, customers will use Netli for their web applications and Akamai or another CDN for their static content delivery, according to senior director of products Brian de Haaff. NetliOffload may reduce this overlap, he suggested.

Big names including Dell, Nokia, Boeing, Thompson, Motorola and Texas Instruments have bought the service since launch in April 2003. de Haaff declined to say how many customers the firm has, but said Netli handles 200 customer domains.

The company has also received $5 million funding from Reed Elsevier, parent of LexisNexis, a customer. We were not looking for more money, because our business plan is fully funded, de Haaff said.