Patent ID: 7860926

Claim:
An information processing system comprising: an information processing apparatus; a server apparatus; and a communication processing apparatus for performing a process operation related to a communication between said information processing apparatus and said sever apparatus; wherein: said information processing apparatus is comprised of: a history packet transmitting unit for transmitting a history packet as part of said communication via a history port of said communication processing apparatus, said history packet corresponding to a packet for leaving a transmission history on said communication processing apparatus; a request packet transmitting unit for transmitting as part of said communication a request packet to said server apparatus via a port different from the history port of said communication processing apparatus, through which said history packet has passed, said request packet requesting a transmission of a return packet from said server apparatus; a packet transmission control unit for controlling transmission of the request packet by said request packet transmitting unit; a return packet receiving unit for receiving the return packet transmitted to said history port of said communication processing apparatus from said server apparatus; and a port keeping time detecting unit for detecting a port keeping time of said communication processing apparatus based upon reception of the return packet by said return packet receiving unit; and wherein: said server apparatus is comprised of: a request packet receiving unit for receiving said request packet; and a return packet transmitting unit for transmitting said return packet to said history port when said request packet receiving unit receives the request packet, wherein the history packet is to be transmitted via said history port in a beginning stage of a wait time, wherein the wait time is a period of time between transmission of the history packet from the history port and an arrival of the return packet at said communication processing apparatus; said packet transmission control unit controls the transmission of said request packet, and controls transmission of the history packet by said history packet transmitting unit; said port keeping time detecting unit detects the port keeping time of said communication processing apparatus based upon the transmission of the history packet by said history packet transmitting unit; and in said port keeping time detecting unit, passage of the history packet through said history port, which corresponds to the beginning stage of said wait time, occurs when said history packet is transmitted.