Communication systems, broadband router, the information processing apparatus and NAT traversal function realizing method used for them

摘要

PROBLEM TO BE SOLVED: To provide a communication system capable of solving the problems of the existing system in the aspects of security and cost.;SOLUTION: A PC 3 on the opposite side transmits address, port and access request to a PC 1 with protocol information added thereto, required for executing an application. On receiving the above access request, a broadband router 2 transmits, to the PC 1, address, port and event message with protocol information added thereto. Based on the address, the port, and the protocol information; the PC 1 decides whether or not the connection request is to be permitted, and transmits an event response when the connection is permitted. On receiving the event response, the broadband router 2 transmits a response to the PC 3 on the opposite side, and notifies the PC 3 on the opposite side that the access request has been permitted. At that time, the broadband router 2 performs port mapping, in response to a port mapping addition request from the PC 1.;COPYRIGHT: (C)2007,JPO&INPIT