America Online (AOL), which has long dominated the instant messaging market, is once again backing away from opening its own system to allow it to communicate with rival networks.
As an alternative, AOL will go after marketing agreements with other companies allowing them to offer their own instant messaging services if they contract AOL to run them.
The internet service provider already has an agreement with Apple, in which the PC maker's upcoming iChat would be facilitated on AOL servers.
But users of other instant messaging services that do not have such agreements, including Yahoo and Microsoft, would not be able to communicate with the 150 million registered AOL subscribers.
AOL has long resisted attempts to force it to join an instant messaging open standards movement.
Company officials could not be reached for comment but, in the past, AOL has cited security and the privacy of its users and its system for the decision.
Last week AOL filed a document on its interoperability testing, which it is required to file every 180 days with the Federal Communications Commission, as a condition of the approval of the merger between AOL and Time Warner in January 2001.
The filing stated: "Despite the ready assurances of other instant messaging providers that interoperability could, and would, be easily and quickly achieved, no other instant messaging service has implemented server-to-server interoperability in the 18 months since the merger order was released."
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