METHOD FOR IMPLEMENTING KEY ESCROW AND KEY RECOVERY IN VOIP SYSTEM AND APPARATUS THEREROF

摘要

A method for performing key escrow and key recovery in a VoIP system and an apparatus using the same are provided to implement a legal interception of a voice by escrowing and recovering the key related to a session determined by an SIP(Session Initiation Protocol) proxy server. A method for performing key escrow and key recovery in VoIP system includes the steps of: if a key escrow request message is received from an SIP proxy server(S310), generating a first cryptogram by encrypting a session key to a session public key based on the received key escrow request message(S320); generating a second cryptogram by encrypting a user ID(Identifier) and the generated first cryptogram to a public key of a key recovery server(S330), and transmitting the generated second cryptogram and the user ID to a database(S340); encrypting the user ID and the session public key to the session key and generating an acknowledgement code(S370); and generating a third cryptogram by encrypting the session key to the public key of the user terminal(S380), and transmitting a key escrow response message having the generated third cryptogram and the generated acknowledgement code to the SIP proxy server(S390).