US 7,529,935 B2
Information communication device, information communication system, and computer program product for transmission control
Takeshi Saito, Meguro-ku (Japan); Hiroshi Isozaki, Kawasaki (Japan); Tatsuyuki Matsushita, Kawasaki (Japan); Taku Kato, Fuchuu (Japan); and Tooru Kamibayashi, Chigasaki (Japan)
Assigned to Kabushiki Kaisha Toshiba, Tokyo (Japan)
Filed on Jun. 28, 2004, as Appl. No. 10/876,705.
Claims priority of application No. P2003-194491 (JP), filed on Jul. 09, 2003; and application No. P2003-406359 (JP), filed on Dec. 04, 2003.
Prior Publication US 2005/0027984 A1, Feb. 03, 2005
Int. Cl. H04L 9/00 (2006.01)
U.S. Cl. 713—168  [713/176; 380/201; 380/229; 380/248] 25 Claims
OG exemplary drawing
 
1. An information communication device for transmitting electronic data encrypted for purpose of copyright protection to another information communication device through a network, the device comprising:
an identification information managing unit configured to hold device identification information identifying other information communication devices acquired through the network;
an ID registration processing unit configured to register the device identification information of the other information communication device when the other information communication device satisfies a predetermined distance condition or when common identification information that is held by both information communication devices is received from a portable device;
an authentication and key exchange processing unit configured to, for purpose of copyright protection, complete an authentication and key exchange process (AKE process) only when the device identification information of the other information communication device is registered in the identification information managing unit, and
a measuring unit configured to measure if the other information communication device satisfies a predetermined distance condition,
wherein the ID registration processing unit is configured to register the device identification information of the other information communication device when the measurement result of the measuring unit indicates that the other information communication device satisfies the predetermined distance condition.