AOL battles rivals

America Online Inc is battling to maintain

a grip on one of its most popular features, instant messaging, after rivals Microsoft Corp

and Yahoo! Inc introduced competing software.

The battle began when Microsoft and Yahoo launched free

software that promised users that they would be able to send instant messages to 40

million AOL customers as well as to members of their own instant messaging communities.

AOL charging that the two companies were making

unauthorized incursions into the company's network infrastructure, quickly blocked the

rival software. Unlike regular e-mail, instant messages pop up immediately on the screen

of the recipient, allowing users to carry on real-time conversations by typing messages

back and forth with friends, selecting from what AOL dubs "buddy lists".

Last year, AOL paid $325 million for the competing ICQ

service, which has an additional 38 million users. AOL says, its networks carry about 780

million messages a day, nearly 12 times the number of regular email messages, sent by 78

million users.

As there are no widely accepted standards for instant

messaging Microsoft used "reverse engineering" and other tactics to dissect

AOL's Software so that users of their new software could communicate with the popular AOL

systems. Yahoo! officials say that they used protocols published by AOL to create their

product.