Patent ID: 8145775

Claim:
A network communication system using extended user datagram protocol (UDP) messages comprising: a requesting apparatus comprising: M numbers of UDP ports configured to receive UDP response messages; UDP buffers configured to temporarily store the UDP response messages received by the M numbers of UDP ports, wherein each of the UDP buffers corresponds to each of the M numbers of UDP ports and, in a case where a specific UDP port of the M numbers of UDP ports receives the UDP response message, the UDP buffer corresponding to the specific UDP port stores the UDP response message temporarily; a generator configured to generate a UDP message, wherein the UDP message has a UDP header section, expanded by adding a first reply-to address corresponding to a first UDP port and a second reply-to address corresponding to a second UDP port to a UDP header section of the norm, including a source port field, a destination port field, a length field and a checksum field for specifying a reply-to address, wherein the requesting apparatus is equipped with the first UDP port and the second UDP port; and a transmitting unit configured to transmit the UDP message to a plurality of connected devices on a network, using a user datagram protocol (UDP), the user datagram protocol not requiring any connection, and a responding apparatus comprising: a selecting unit configured to randomly select one reply-to address from among the first reply-to address and the second reply-to address, written in a UDP message transmitted by the transmitting unit when responding to the UDP message transmitted by the transmitting unit; and a responding unit configured to return a response message corresponding to the UDP message to the first UDP port in a case where the first reply-to address is selected by the selecting unit and to the second UDP port in a case where the second reply-to address is selected by the selecting unit.