Showing papers by "Takeshi Kubo published in 2006"

Communication device in ad hoc mode in radio lan, setting program, and connection method

Abstract: PROBLEM TO BE SOLVED: To provide a communication device for avoiding a state, where a multi hop communication is disabled by the disagreement of IBSSID (Infrastructure-mode Basic Service Set IDentifier) in the ad hoc mode of IEEE802.11 radio LAN, and to provide a program and a connection method. SOLUTION: ESSID (Extended Service Set IDentifier, a maximum of 32 alphanumeric characters (256 bits)) is set to IBSSID (6 bytes (48 bits)). Especially, a value derived from a specific rule, for example a unidirectional function, is set to IBSSID from ESSID. If the ESSID of a received beacon signal has already been registered but the IBSSID of the received beacon signal has not been registered yet when receiving the beacon signal, information on the overlapping of IBSSID is alarmed and displayed to a user. COPYRIGHT: (C)2006,JPO&NCIPI

Multi-hop communication system and mobile terminal thereof, routing control server, and routing establishment method

Abstract: PROBLEM TO BE SOLVED: To provide a multi-hop communication system and a mobile terminal thereof capable of securely realizing multi-hop communication when at least one of a plurality of terminals acting like relay stations is located within the zone of an infrastructure network, and to provide a routing control server and a routing establishment method SOLUTION: A transmission terminal S applies flooding of an RREQ to whole mobile terminals, the RREQ resulting from encrypting a sender address IPs and a destination address IPt by a public key KRMp, and the mobile terminal X in a zone receiving the RREQ requests a server RM to assign anonymous addresses FWs, FWt to the mobile terminal X The server RM interprets the sender address IPs and the destination address IPt by using a private key KRMs, encrypts them again by using a shared key KRM_t unique to the destination terminal T, and returns the re-encrypted shared key KRM_t together with the anonymous addresses FWs, FWt to the mobile terminal X in the form of a FWREP The mobile terminal X registers the addresses IPs, IPt and the anonymous addresses FWs, FWt re-encrypted by using the shared key KRM_t to an RREQ and applies flooding of the resulting RREQ to the whole mobile terminals COPYRIGHT: (C)2007,JPO&INPIT

Method and system of authenticating user, authentication server and communication terminal

Abstract: PROBLEM TO BE SOLVED: To provide a method and a system of authenticating a user which does not need authentication in the authentication server of a home domain as much as possible by causing the authentication server of an external domain to perform authentication in a roaming environment, and to provide an authentication server to be used in the system and a communication terminal SOLUTION: Each authentication server stores an encryption domain key of a domain capable of roaming A communication terminal to be authenticated transmits a ticket having authentication information encrypted with the domain key of the home domain of the communication terminal to the authentication server, together with user identification information and home domain identification information The authentication server having received the ticket determines the stored domain key of the home domain of the communication terminal on the basis of the home domain identification information to be received, and uses the determined domain key to decrypt the identification information of the ticket to perform authentication COPYRIGHT: (C)2006,JPO&NCIPI

Ad hoc multi-hop communication system, its wireless terminal, and ad hoc multi-hop network connection method

Abstract: PROBLEM TO BE SOLVED: To obtain coincidence in IBSSID of a storage terminal by automatically performing convergence into one value in a wireless ad hoc network. SOLUTION: A wireless ad hoc communication system is constituted of a plurality of wireless terminals. Each wireless terminal comprises a means for storing ESSID; a means for storing the IBSSID; a means for storing scale information which represents the scale of a network to which the terminal itself belongs; a means for periodically transmitting a beacon with the ESSID, the IBSSID, and the scale information N registered therein; a means for receiving the beacon transmitted from another wireless terminal; and a control means for changing the self IBSSID and the scale information N, based on the IBSSID and scale information N registered in the beacon where the ESSID is coincident with that of the terminal itself. When the self scale information N is not larger than the received scale information N, the control means changes the self IBSSID and scale information N in response to the received IBSSID and scale information N. COPYRIGHT: (C)2006,JPO&NCIPI

Routing correction method and system

Abstract: PROBLEM TO BE SOLVED: To provide a routing correction method and system for correcting routing wherein data communication whose anonymousness and confidentiality are not lost is attained through the use of anonymous addresses in a way that the anonymousness and the confidentiality are not lost. SOLUTION: The routing correction method includes: a step in which a terminal detecting an interrupted link transmits an RERR by using an anonymous address; a step in which one end terminal receiving the RERR generates an RRPR and transmits the RRPR by using the anonymous address; a step in which a terminal receiving the RRPR relays the RRPR; a step in which the other end terminal receiving the RRPR generates an RREP_R and transmits the RREP_R to the one end terminal by utilizing the anonymous address; a step in which a terminal receiving the RREP_R relays the RREP_R; and a step in which the terminal relaying the RRPR and the RREP stores the anonymous address as routing information. The relaying of the RRPR and the RREP_R is carried out between terminals opposed to each other across the interrupted link by using flooding whose destination is made a broadcast address and executed by utilizing the anonymous address in other cases. COPYRIGHT: (C)2007,JPO&INPIT

Reestablishing method for ppp connection in cdma network system

Abstract: PROBLEM TO BE SOLVED: To provide a method of reestablishing a PPP connection in a CDMA network system with a simple sequence SOLUTION: A terminal 5 establishes the PPP connection with a PDSN 10 via a PCF 20 (S107), the PDSN 10 for recognizing interruption opportunity by a handover (S108) transmits PPP session information in the terminal 5 to a session information storage device 8 (S400), a PCF 21 acquires a first IMSI key from the PCF 20 (S403), acquires a second IMSI key from the terminal (S405), compares both the IMSI keys (S406), when both the IMSI keys are coincident, a PDSN 11 connected to the PCF 21 acquires PPP session information from the session information storage device 8 (S408), and the PDSN 11 restores and reestablishes the PPP connection with the terminal 5 (S409) COPYRIGHT: (C)2006,JPO&NCIPI

Packet transfer device based on address including geographic information, and its system and program

Abstract: PROBLEM TO BE SOLVED: To provide a packet transfer device transferring a packet according to an address including geographic information, without performing functional append or exchange for all of existing routers. SOLUTION: The packet transfer device according to the present invention is a GIP packet transfer device for transferring a packet according to geographic information. The device comprises: a means for saving a routing table of GIP packet transfer; a means for determining whether a received packet is a GIP packet, an encapsulated GIP packet; a means for determining other GIP packet transfer device to which a GIP packet should be transmitted, on the basis of an area specified by the geographic information and the routing table, when the received packet is a GIP packet or an encapsulated GIP packet; and a means for transmitting an encapsulated GIP packet when transmission to the other GIP packet transfer device travels via a packet transfer device which does not recognize geographic information of a destination address of the GIP packet. COPYRIGHT: (C)2006,JPO&NCIPI

Forwarding performance improvement of a mobile IP home agent

Abstract: In Mobile IP networks, the home agent manages the destination information of all mobile terminals. It receives as proxy the packets destined for the mobile terminal and transfers them to the new location of the terminal. When the number of terminals in the network is increased, the home agent must manage a large amount of information, which increases the retrieval processing load in packet transfer. It is possible that a packet may be lost by an overloaded home agent. This paper proposes a method of eliminating the retrieval processing of the home agent in packet transfer by utilizing ARP, and of reducing the load of the whole packet transfer process. It is shown experimentally that even if sufficient mobile terminal entries to completely fill the location information list for 200,000 entries are registered, the home agent can transfer all packets without any packet loss in Fast Ethernet. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 89(6): 32–40, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20249