Patent ID: 8156242

Claim:
A command processing apparatus for executing a process according to a command sent from an external server through a router, out of a first system continuously releasing a specific port in response to a port releasing request and being compliant with a UPnP protocol and a second system performing an information sending in response to an information send request and temporarily releasing an arbitrary port, the router being compliant with at least said second system, comprising: a determining device that determines whether or not said router is compliant with said first system; a first issuer that issues said port releasing request to said router when the determination result by said determining device is affirmative; a send requestor that requests said router to send destination information including an identifier of said specific port released in response to said port releasing request to said external server; and a second issuer, wherein when it is determined that the determination result by said determining device is negative, said command processing apparatus shifts process to determine an optimal send interval, and said second issuer repeatedly issues said information send request to said router at the optimal send interval, said information send request issued by said second issuer being a send request of the destination information including the identifier of said arbitrary port to said external server.