<p>A TCP session emulator comprising a session search table searched for an identifier for specifying a session of the TCP protocol by using at least the IP (Internet Protocol) acquired from the header of the received packet or the port number as the search key, a session status management memory for acquiring the session status code provided according to the identifier acquired by the search, and a sequencer for determining a pseudo-session operation of the TCP protocol used by one of application protocols according to the session status code acquired from the session status management memory.</p>
