1. A method of controlling a blind/attended transfer in a Session Initiation Protocol (SIP)-based network in which a first SIP-based terminal communicating with a second terminal through an SIP server transfers a call to a third terminal, the method comprising: transmitting a call request message from the first SIP-based terminal to the third terminal after pausing a communication with the second terminal by transmitting a call waiting message to the SIP server, the call request message being an object of the call transfer; determining whether a call transfer function (Hook on) has been activated prior to receiving a call response (200OK) signal from the SIP server, the determination being made by the first SIP-based terminal; and performing the blind transfer with the third terminal by transmitting a call transfer message (REFER) to the SIP server upon the call transfer function (Hook on) being activated prior to receiving the call response message from the SIP server, the blind transfer being performed by the first SIP-based terminal.