SIP Service Providers and The Spam Problem

The Session Initiation Protocol (SIP) is used for managing multimedia sessions in the Internet. As an emerging standard gaining more and more acceptance within the IT community, SIP will probably be the target of spammers. We propose, in this paper, a reputation-based mechanism that builds trust between users within a SIP community and prevents spammers to carry out attacks. Our technique uses a social networks approach enhanced with some reputation ratings. A metric for computing reputation is defined and an algorithm allowing the users to evaluate each other is also presented.