Patent ID: 8055777

Claim:
An information processing apparatus which can be installed in a DMZ and is connectable to an intranet through a first firewall and to an external network through a second firewall, the information processing apparatus comprising: a first processing unit for pre-establishing a first connection from the intranet through the first firewall to the first processing unit, and then transmitting or receiving, over the first connection and the intranet, a first signaling message for establishing a call, in accordance with an H.323 standard or a Session Initiation Protocol (SIP), and transmitting or receiving a second signaling message for establishing a call in accordance with the H.323 standard or the SIP, over a second connection which is dynamically established through the second fire wall over the external network, wherein a transmission of one of the first and second signaling messages occurs in response to a reception of another one of the first and second signaling messages so that the one of the first and second signaling messages is associated with the another one of the first and second signaling messages, and a reception and a transmission of the another one of the first and second signaling messages cause a call to be established over both of the intranet and the external network via the DMZ; and a second processing unit for transmitting and receiving data over the established call via the DMZ through the first and second firewalls, wherein, before the transmission or reception of the first signaling message, the first connection with the first processing unit is established by a third processing unit which is connectable to the intranet, and wherein the first processing unit causes the third processing unit to transmit or receive a third signaling message for establishing a call to or from a first terminal over the intranet, and transmits or receives the second signaling message to or from a second terminal over the external network, to thereby cause the call to be established between the first terminal and the second terminal.