Patent ID: 8165042

Claim:
A data communication apparatus for communicating, via a network, with a network device that can be assigned a plurality of addresses per one name, comprising: an acquisition unit, configured to acquire an address corresponding to a name of a transmission destination; a transmission unit, configured to transmit transmission data, together with identification information that identifies the transmission data, to the acquired address; a reception unit, configured to receive response data having identification information corresponding to transmission data; a determination unit, configured to determine, based upon the identification information of the transmission data transmitted by the transmission unit and the identification information of the response data, whether the received response data is a response to the transmission data transmitted by the transmission unit; and a response processing unit, configured to discard the response data if the determination unit determines that the response data is not a response to the transmission data transmitted by the transmission unit, and delivering data contained in the response data to a source requesting the data transmission if the determination unit determines that the response data is a response to the transmission data transmitted by the transmission unit, wherein if an address corresponding to the name of the transmission destination is not found, said acquisition unit transmits the name of the transmission destination to a DNS server and, if a plurality of addresses have been assigned to the transmission destination, collectively acquires the plurality of addresses.