Patents by Inventor Hiroaki Nakazawa
Hiroaki Nakazawa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 9407389Abstract: In an extensive distribution system with no delay guarantee network used as a relay network, an influence of a fluctuation of a communication delay time is avoided to conduct a high-precision time synchronization. First and second delay control devices installed in junctions between communication networks and a relay network, respectively, have functions of retaining first and second time information, and setting a first relay network passing time of a first communication signal directed from a time dissemination device toward a time receiving device through a relay network, and a second relay network passing time of a second communication signal directed from the time receiving device toward the time dissemination device, respectively. In measurement of communication delay time of the first communication network and the second communication network prior to time synchronization, the first and second relay network passing times are unified in advance to exclude uncertainty of the communication time.Type: GrantFiled: August 7, 2014Date of Patent: August 2, 2016Assignee: Hitachi, Ltd.Inventors: Masahiko Mizutani, Hiroaki Nakazawa, Yoshihiro Ashi, Daiji Mitsunaga, Hideyuki Nakanishi
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Publication number: 20150085852Abstract: In an extensive distribution system with no delay guarantee network used as a relay network, an influence of a fluctuation of a communication delay time is avoided to conduct a high-precision time synchronization. First and second delay control devices installed in junctions between communication networks and a relay network, respectively, have functions of retaining first and second time information, and setting a first relay network passing time of a first communication signal directed from a time dissemination device toward a time receiving device through a relay network, and a second relay network passing time of a second communication signal directed from the time receiving device toward the time dissemination device, respectively. In measurement of communication delay time of the first communication network and the second communication network prior to time synchronization, the first and second relay network passing times are unified in advance to exclude uncertainty of the communication time.Type: ApplicationFiled: August 7, 2014Publication date: March 26, 2015Applicant: HITACHI, LTD.Inventors: Masahiko MIZUTANI, Hiroaki NAKAZAWA, Yoshihiro ASHI, Daiji MITSUNAGA, Hideyuki NAKANISHI
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Patent number: 7830886Abstract: A boundary node router determines whether a received packet includes a SIP message and a REGISTER message, and, if so, adds its router identifier to a REGISTER message which includes a user identifier and a user terminal identifier, sent from a user terminal, and sends the message to a SIP server. The SIP server has a user management table which stores the user terminal identifier, the router identifier of a router which serves the user terminal, and a predetermined Quality of Service type, in association with each user identifier. The SIP server extracts a user identifier, a user terminal identifier, and a router identifier from a received REGISTER message, and updates the user terminal identifier and the router identifier corresponding to the extracted user identifier, to the extracted user terminal identifier and the extracted router identifier.Type: GrantFiled: December 6, 2007Date of Patent: November 9, 2010Assignee: Hitachi, Ltd.Inventors: Hiroaki Nakazawa, Atsushi Tachikawa
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Patent number: 7680121Abstract: A transmission apparatus connected to a first network obtains information on a device connected to a third network, to which a destination of communication with a communication device connected to a second network is connected, and transmits the obtained information to a device connected to the second network via the first network.Type: GrantFiled: July 16, 2004Date of Patent: March 16, 2010Assignee: Canon Kabushiki KaishaInventors: Katsuhisa Ogawa, Masahiko Kosaka, Naohiko Suzuki, Hiroaki Nakazawa
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Patent number: 7664954Abstract: A providing apparatus that provides information required for a secure communication to first and second devices includes a receiving unit for receiving candidates for parameters used for the secure communication from the first and second devices; a generating unit for generating the information required for the secure communication based on the candidates for the parameters received from the first and second devices; and a transmitting unit for transmitting the information required for the secure communication, generated by the generating unit, to the first and second devices.Type: GrantFiled: March 22, 2005Date of Patent: February 16, 2010Assignee: Canon Kabushiki KaishaInventors: Katsuhisa Ogawa, Naohiko Suzuki, Hiroaki Nakazawa
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Patent number: 7542573Abstract: A providing apparatus provides information required for secure communication to first and second devices. The providing apparatus includes a receiving unit that receives a first parameter used by the first device for the secure communication and a second parameter used by the second device for the secure communication from a connection apparatus via which the first device is connected to the second device, a generating unit that generates the information required for the secure communication based on the parameters received from the connection apparatus, and a transmitting unit that transmits the information required for the secure communication, generated by the generating unit, to the first and second devices.Type: GrantFiled: May 23, 2005Date of Patent: June 2, 2009Assignee: Canon Kabushiki KaishaInventors: Katsuhisa Ogawa, Naohiko Suzuki, Hiroaki Nakazawa
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Patent number: 7457875Abstract: An access server starts the individual collection of communication statistics information on each of LCP sessions upon the establishment of a data link, individually collects communication statistics information on each of NCP sessions established on the LCP session, notifies a RADIUS server of the statistics information on the LCP session when the data link is released, and notifies, when the NCP session is released, the RADIUS server of the statistics information on the released NCP session.Type: GrantFiled: July 26, 2004Date of Patent: November 25, 2008Assignee: Hitachi Communication Technologies, Ltd.Inventors: Mitsuhiro Wada, Hiroaki Nakazawa, Noriyuki Sueyoshi, Yasuo Murakami, Hiroaki Miyata
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Patent number: 7415536Abstract: Upon reception of a query about the address of a server from a client, a DNS server sends a query about the address of that server to an external DNS server. The DNS server checks based on the address obtained from the external DNS server if connection to the server can be established. If connection to the server cannot be established, and the DNS server receives a query about the address of the server, the DNS server returns a response indicating that the address is not available. When the address is returned before the check process, the DNS sever sets an expiration time shorter than that of the address of the server obtained from the external DNS server as the expiration time of the address of the server.Type: GrantFiled: January 13, 2004Date of Patent: August 19, 2008Assignee: Canon Kabushiki KaishaInventor: Hiroaki Nakazawa
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Patent number: 7404008Abstract: There is provided an address translator having the functions to prevent, in the communications via the address translation, transmission of packets having no correct destination and transmission source addresses which will cause troubles in the networks and to urge an administrator take adequate measures for reception of the relevant packets. This address translator stores discriminator to discriminate temporary addresses. Moreover, when the original address is registered as the temporary address at the time of assignment of the temporary address of the receiving side host started when the name solution is performed, assignment is rejected to prevent transmission of packet from the transmitting side host by returning a response for name solution error to the transmitting side host. In addition, when transmission source address before translation and destination address after translation are registered as the temporary address, the received packet is discarded.Type: GrantFiled: August 20, 2003Date of Patent: July 22, 2008Assignee: Hitachi, Ltd.Inventors: Keisuke Takeuchi, Tetsuhiko Hirata, Hiroaki Nakazawa
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Publication number: 20080095158Abstract: A boundary node router determines whether a received packet includes a SIP message and a REGISTER message, and, if so, adds its router identifier to a REGISTER message which includes a user identifier and a user terminal identifier, sent from a user terminal, and sends the message to a SIP server. The SIP server has a user management table which stores the user terminal identifier, the router identifier of a router which serves the user terminal, and a predetermined Quality of Service type, in association with each user identifier. The SIP server extracts a user identifier, a user terminal identifier, and a router identifier from a received REGISTER message, and updates the user terminal identifier and the router identifier corresponding to the extracted user identifier, to the extracted user terminal identifier and the extracted router identifier.Type: ApplicationFiled: December 6, 2007Publication date: April 24, 2008Inventors: Hiroaki Nakazawa, Atsushi Tachikawa
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Patent number: 7330470Abstract: A boundary node router determines whether a received packet includes a SIP message and a REGISTER message, and, if so, adds its router identifier to a REGISTER message which includes a user identifier and a user terminal identifier, sent from a user terminal, and sends the message to a SIP server. The SIP server has a user management table which stores the user terminal identifier, the router identifier of a router which serves the user terminal, and a predetermined Quality of Service type, in association with each user identifier. The SIP server extracts a user identifier, a user terminal identifier, and a router identifier from a received REGISTER message, and updates the user terminal identifier and the router identifier corresponding to the extracted user identifier, to the extracted user terminal identifier and the extracted router identifier.Type: GrantFiled: January 12, 2005Date of Patent: February 12, 2008Assignee: Hitachi Communication Technologies, Ltd.Inventors: Hiroaki Nakazawa, Atsushi Tachikawa
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Patent number: 7123599Abstract: A mobile data communication system capable of shortening the interruption time of communication includes an HA device, advertising routers, base stations, routers, and mobile terminal devices. Each base station advertises an address having “1” set in a different bit of an interface ID of a routing address. When a mobile terminal has received radio waves from a plurality of base stations in the vicinity of a boundary between cells, the mobile terminal combines a plurality of received routing addresses by logical summation and registers a resultant routing address with the HA device. As for a packet delivered from the HA device to the routing address and having “1” in a plurality of bits of the host section, a router resolves the address of the host section into destination addresses each having “1” in one bit, generates packets each having one of resultant addresses, and transmits the generated packets.Type: GrantFiled: February 28, 2002Date of Patent: October 17, 2006Assignee: Hitachi, Ltd.Inventors: Masashi Yano, Tetsuhiko Hirata, Masaya Hayashi, Hiroaki Nakazawa
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Publication number: 20050280649Abstract: In a character provision service system for providing users with characters such as interface agents and virtual characters in virtual spaces on computers or in TV games, charges for use of a provided character is computed according to a motion made by the character. This system enables each user to easily purchase with security a character capable of moving according user's need, and also enables character data providers to collect charges according to motions made by provided characters and to provide various characters without anxiety about unauthorized use of the characters.Type: ApplicationFiled: August 16, 2005Publication date: December 22, 2005Applicant: CANON KABUSHIKI KAISHAInventors: Hiroaki Nakazawa, Tsuyoshi Yagisawa, Kazue Kaneko, Takashi Aso, Makoto Hirota, Kazuko Suzuki
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Publication number: 20050273595Abstract: A providing apparatus provides information required for secure communication to first and second devices. The providing apparatus includes a receiving unit that receives a first parameter used by the first device for the secure communication and a second parameter used by the second device for the secure communication from a connection apparatus via which the first device is connected to the second device, a generating unit that generates the information required for the secure communication based on the parameters received from the connection apparatus, and a transmitting unit that transmits the information required for the secure communication, generated by the generating unit, to the first and second devices.Type: ApplicationFiled: May 23, 2005Publication date: December 8, 2005Applicant: Canon Kabushiki KaishaInventors: Katsuhisa Ogawa, Naohiko Suzuki, Hiroaki Nakazawa
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Patent number: 6956575Abstract: In a character provision service system for providing users with characters such as interface agents and virtual characters in virtual spaces on computers or in TV games, charges for use of a provided character is computed according to a motion made by the character. This system enables each user to easily purchase with security a character capable of moving according user's need, and also enables character data providers to collect charges according to motions made by provided characters and to provide various characters without anxiety about unauthorized use of the characters.Type: GrantFiled: July 27, 2001Date of Patent: October 18, 2005Assignee: Canon Kabushiki KaishaInventors: Hiroaki Nakazawa, Tsuyoshi Yagisawa, Kazue Kaneko, Takashi Aso, Makoto Hirota, Kazuko Suzuki
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Publication number: 20050223228Abstract: A providing apparatus that provides information required for a secure communication to first and second devices includes a receiving unit for receiving candidates for parameters used for the secure communication from the first and second devices; a generating unit for generating the information required for the secure communication based on the candidates for the parameters received from the first and second devices; and a transmitting unit for transmitting the information required for the secure communication, generated by the generating unit, to the first and second devices.Type: ApplicationFiled: March 22, 2005Publication date: October 6, 2005Applicant: Canon Kabushiki KaishaInventors: Katsuhisa Ogawa, Naohiko Suzuki, Hiroaki Nakazawa
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Publication number: 20050213591Abstract: A boundary node router determines whether a received packet includes a SIP message and a REGISTER message, and, if so, adds its router identifier to a REGISTER message which includes a user identifier and a user terminal identifier, sent from a user terminal, and sends the message to a SIP server. The SIP server has a user management table which stores the user terminal identifier, the router identifier of a router which serves the user terminal, and a predetermined Quality of Service type, in association with each user identifier. The SIP server extracts a user identifier, a user terminal identifier, and a router identifier from a received REGISTER message, and updates the user terminal identifier and the router identifier corresponding to the extracted user identifier, to the extracted user terminal identifier and the extracted router identifier.Type: ApplicationFiled: January 12, 2005Publication date: September 29, 2005Inventors: Hiroaki Nakazawa, Atsushi Tachikawa
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Publication number: 20050198277Abstract: An access server starts the individual collection of communication statistics information on each of LCP sessions upon the establishment of a data link, individually collects communication statistics information on each of NCP sessions established on the LCP session, notifies a RADIUS server of the statistics information on the LCP session when the data link is released, and notifies, when the NCP session is released, the RADIUS server of the statistics information on the released NCP session.Type: ApplicationFiled: July 26, 2004Publication date: September 8, 2005Inventors: Mitsuhiro Wada, Hiroaki Nakazawa, Noriyuki Sueyoshi, Yasuo Murakami, Hiroaki Miyata
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Publication number: 20050036491Abstract: A transmission apparatus connected to a first network obtains information on a device connected to a third network, to which a destination of communication with a communication device connected to a second network is connected, and transmits the obtained information to a device connected to the second network via the first network.Type: ApplicationFiled: July 16, 2004Publication date: February 17, 2005Inventors: Katsuhisa Ogawa, Masahiko Kosaka, Naohiko Suzuki, Hiroaki Nakazawa
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Publication number: 20040230830Abstract: A receiver receives first and second signals (first and second receiver signals) and permits connection with a connection request source (transmitter) on the basis of a port number included in the second signal (second receiver signal) when the first signal (first receiver signal) satisfies a predetermined condition. The port for accepting the connection request may be variable. The second signal (second receiver signal) may include data designating a program. A connection controller may receive a first signal (first controller signal) from the receiver and send a second signal (second controller signal) to a transmitter, the second signal (second controller signal) designating the port of the receiver for accepting the connection request from the transmitter.Type: ApplicationFiled: May 10, 2004Publication date: November 18, 2004Applicant: Canon Kabushiki KaishaInventors: Katsuhisa Ogawa, Masahiko Kosaka, Naohiko Suzuki, Hiroaki Nakazawa