SIP Security
Abstract: Session Initiation Protocol is a signaling protocol standardized by IETF. It is used to establish, modify and terminate sessions. Since SIP offers a simple and fast way to setup sessions, it has become a very important signaling protocol in VoIP market; meanwhile, SIP security also becomes a big concern.
To achieve SIP functionality, four logic components are needed: user agent, location service, proxy server, registrar, and redirect server. After analyzing the message flow of SIP session setup and tear up, we can easily to figure out possible threats in SIP: registration hijacking, proxy impersonation, message tampering, session tear down, and DOS.
In my presentation, I first will explain the functionality of SIP, and show typical message flow in SIP. Secondly, I will go over each threat in SIP system. At the end, I will show the promoted security mechanisms to prevent these threats.