Internet service provider EarthLink has installed Akamai hardware and software throughout its network to improve content delivery to its 4.8 million subscribers.

Financial terms were not disclosed. The agreement follows an extensive trial period where EarthLink conserved bandwidth while at the same time cutting download waits for Internet content, including dynamic HTML and streaming media.

"Given its substantial presence and subscriber base, EarthLink is an important, strategic network partner for Akamai, and we're excited about this landmark relationship," said Jonathan Stefansky, an Akamai vice president.

The deal is the second piece of news from Cambridge, Mass.-based Akamai this week. Earlier, it said Digex, a Laurel, Md., Web host will begin offering Akamai's EdgeSuite product to its large corporate customers.

For Atlanta-based EarthLink, the pact should go a long way toward customer satisfaction -- a key concern in the highly competitive ISP market.

"This agreement underscores EarthLink's commitment to maintaining a top quality Internet experience for our subscribers," said Steve Dougherty, of EarthLink. "The installation of Akamai's servers provides the two-fold benefit of reduced bandwidth costs and maximum performance of some of the world's most popular Internet content."

Shares of AKAM were up 0.27, or 6 percent, to 4.68 in morning trading, while ELNK stock shed 0.5, or nearly 5 percent, to 9.8.