Introduction - If you have any usage issues, please Google them yourself
A java-rmi chat-room,instant messaging is one particular application in a broader class of applications known
as presence-based applications. Presence-based applications are inherently distributed
applications that build on the notion of a user’s (or computer’s) virtual presence in a
particular network context. While most popular instant messaging systems (AIM, Yahoo,
MSN) are proprietary implementations1, conceptually they are very similar.