Presence Management—More Than Instant Messaging

Most Internet users know Instant Messaging through services such as AOL Instant Messaging (AIM) or Microsoft Messenger. AIM was derived from the ICQ model developed in 1996 as the service of Mirabillis (acquired by AOL in 1998). According to IDC, by 2006 there will be 255 million users worldwide—both consumers and enterprises—of instant messaging, almost three times the number of users in 2002. The phenomenal growth within enterprises is equally impressive. Businesses are integrating presence management with their IP telephony system so that a user's on-hook or off-hook status is available to subscribers.

Presence promises to change user behavior as callers come to depend on knowing the availability of someone they want to contact in advance of initiating a call. They can avoid making the call altogether by "pinging" the user with a short message.