EarthLink said its new service, which was announced Tuesday, is available to its 1.2 million high-speed subscribers, who pay between $42 and $49 per month. "This is a window into what the future looks like," said Tom Andrus, vice president of products and services at EarthLink. "Anyone who's online can call anyone online for free."

For now, subscribers are limited to who they can speak to since EarthLink's phone service is a closed network, much like instant messaging networks of Time Warner's AOL, Microsoft and Yahoo .

Andrus said the service is similar to Skype, a free Internet telephone service, but doesn't interoperate with it. Andrus said EarthLink's service interoperates with other services, such as SIPphone and Free World Dialup.

EarthLink has no plans to offer free Web calling service to Internet subscribers of rival high-speed access providers.

변화의 방향을 알았다면, 그 다음은 변화의 속도를 알아야한다. 둘 중 하나라도 삐끗하면 실패 밖에 없다.