AOL has proposed a standards protocol for instant messaging to the Internet Engineering Task Force (IETF), a week after the US Federal Communications Commission began an investigation into AOL's instant messaging service. The IMX Architecture would allow "disparate systems to exchange messages and presence information," according to the draft standard. Rival services have complained that the popular service provider was blocking their customers from communicating with AOL Instant Messenger (IM) users, though companies like Microsoft, iCast, and Tribal Voice had configured their messaging software to work with AOL's. AOL has by far the largest number of instant-message users in the market. AOL's IM and ICQ control 90 per cent of the instant-messaging market, according to an iCast estimate. Some critics say the 18-page standards proposal is an attempt to distract the government's antitrust investigation, spurred on in part by the proposed merger of AOL and Time Warner. Antitrust enforcers at the FCC asked AOL in a letter to supply information about its activity in instant messaging, including its work toward creating an interoperability standard. Among the information the FCC is seeking are details about AOL's co-operation with other instant-messaging providers on creating the standard and whether customers of other instant messaging products can connect with customers of AOL's instant messaging products. In the latest skirmish between AOL and an instant messaging competitor, AOL this week blocked Odigo Odigo Messenger from interacting with IM users. Odigo responded with a news release in which it said Odigo Messenger users could download a patch for free at the Odigo Web site that restored interoperability between Odigo Messenger and AOL IM. Ross Bagally, CEO of Tribal Voice, wasn't satisfied with the AOL proposal. "What they are talking about would take a very long time to accomplish," he said, especially since there is no time frame for implementation. In addition, "within an hour of releasing the protocol proposal, they blocked Odigo again," Bagally said. "There is no indication that AOL wants to open up the market." The standards proposal came at the same time AOL was blocking IM users from services like iCast and Tribal Voice. The ITEF is an international organization that oversees Internet technical standards. In a statement, AOL said its standards would offer the following: 1) Privacy and security. Users would only need to register with one system, and passwords and log-in IDs wouldn't need to be shared outside their initial network. 2) Scalability. The architecture would support everything from large networks like AOL's to individual companies or consumers with their own servers. 3) Independence. There would be no central authority needed to administer the system. 4) Log-in name consistency. Users could keep their existing names, even if another user had the same log-in name on another network.