Patent ID: 7664837

Claim:
A data transmitting system for transmitting data to be processed through a TCP/IP-based network to which a plurality of devices including a first device and a second device are connected, the data to be processed being transmitted by said first device and received by said second device, said first device including: an identification information obtaining system that transmits first data through the network using a first address which does not specify a destination to obtain identification information of the plurality of devices except said first device, wherein the first data is a search packet that includes a destination address, which indicates the search packet as a broadcast packet, a source address, which indicates a MAC address of the first device, and a second multicast address for receipt of a search reply, said second device including: an identification information transmitting system that transmits second data containing the identification information of said second device through the network using the second multicast address in response to the first data transmitted by said identification information obtaining system of said first device, wherein the second data being the search reply that includes a destination address, which indicates the MAC address of the first device, a source address field, which is the identification information that indicates a MAC address of the second device; said first device further including: a selecting system that selects one of the second devices that transmits the identification information to said identification information obtaining system of said first device; a join request transmitting system that transmits third data to the second device selected as the destination of the data to be processed, wherein the third data is a join request packet that includes the MAC address of the selected second device and requests the selected second device to join a multicast group such that the first device and the selected second device can communicate with each other using a specific multicast address; and a data transmitting system that transmits the data to be processed through the network to the selected second device using a third multicast address, which is the specific multicast address, said second device further including: an acknowledgment transmitting system that receives the join request packet, determines whether it is possible to join the multicast group, and replies to the first device using the second multicast address with either a join success reply packet or a join unsuccessful reply packet; and a data receiving system that is configured to receive the data to be processed transmitted from said data transmitting system of the first device using the third multicast address if the data transmitted from said data transmitting system is data having said second device as the designated destination.