A new negotiation mechanism for cryptographic capabilities in SIP based secure VoIP service using priority

MIKEY (Multimedia Internet KEYing) has been proposed as a key management protocol for secure multimedia communication, which the security protocol (Secure RTP) for media encryption has considered. Since initiator and responder have different cryptographic capabilities, a negotiation mechanism, which can enable them to communicate each other securely, is required. But previous negotiation methods have several problems, which cannot satisfy backward compatibility and determine their favorite cryptographic capabilities. So we propose new negotiation mechanism, which can solve these problems using priority.