Towards an open protocol for secure online presence notification

摘要

It is important to know the presence of other concurrently online users before real-time communication can be established with them. While many instant messaging (IM) systems are available, there is no standard protocol for online presence notification due to the proprietary nature of such systems. These systems generally have many security weaknesses such as anonymous messaging, message spoofing, account hijacking and authorization overriding because they depend heavily on client-side operations.