Abstract: A voice communication system, which is connected to a LAN to which communication terminals are connected and to a public network to which telephones are connected, is provided with a communication server between the LAN and public network having different protocols from each other. The communication server enables a voice communication between a telephone on the public network and a communication terminal connected to the LAN by performing processing similar to that for a voice communication between two communication terminals connected to the LAN. The communication server determines whether an address of the other party inputted by a user is a communication terminal address or a telephone number, and transmits a voice communication request to a communication terminal of the other party when the address is a communication terminal address.

Abstract: A voice communication system, which is connected to a LAN to which communication terminals are connected and to a public network to which telephones are connected, is provided with a communication server between the LAN and public network having different protocols from each other. The communication server enables a voice communication between a telephone on the public network and a communication terminal connected to the LAN by performing processing similar to that for a voice communication between two communication terminals connected to the LAN. The communication server determines whether an address of the other party inputted by a user is a communication terminal address or a telephone number, and transmits a voice communication request to a communication terminal of the other party when the address is a communication terminal address.

Abstract: A voice communication system, which is connected to a LAN to which communication terminals are connected and to a public network to which telephones are connected, is provided with a communication server between the LAN and public network having different protocols from each other. The communication server enables a voice communication between a telephone on the public network and a communication terminal connected to the LAN by performing processing similar to that for a voice communication between two communication terminals connected to the LAN. The communication server determines whether an address of the other party inputted by a user is a communication terminal address or a telephone number, and transmits a voice communication request to a communication terminal of the other party when the address is a communication terminal address.

Abstract: In a network system including a first relay connected to a wire network and a radio network, a second relay for relaying data in the radio network, a first terminal connected by wireless to the first relay, and a second terminal connected by wireless to the second relay, the first relay keeps first information indicating a correspondence between an address of the second terminal, an identifier of a group to which the second terminal belongs, and an identifier of the second relay and second information indicating a correspondence between identifiers of groups formed by virtually subdividing the wire network and an identifier of a group to which the second terminal belongs, and the first relay transmits a packet according to the first or second information.

Abstract: A first and a second terminal carry out radio communications, the first terminal selects, based on an expectation saved in the concerned first terminal, a relay terminal relaying data to be transmitted to the second terminal and transmits the data, with a first information item indicating the address of the first terminal and a second information item indicating the address of the second terminal, to the relay terminal; and the relay terminal transmits the received first and second information items, and the data, to the second terminal; and if the second terminal receives the first and second information items, and the data, it transmits a completion report to the first terminal, based on expectation values saved by the second terminal concerned, making it capable of checking whether it has been possible to surely send and deliver the data.

Abstract: In order to efficiently use each of storage physical devices fast in access rate for each data block even where a deviation in access frequency exists within a file, in a storage system comprising a plurality of the storage physical devices, a policy is stored within the storage system in advance with respect to the placement of file's data blocks, and data of each file is evaluated with respect to the policy upon storage of the file's data blocks. A decision as to in which storage physical device the corresponding data blocks should be located, is made based on the evaluation result of the policy.

Abstract: Disclosed is a glide head for a magnetic disk that has a high sensitivity for efficiently transmitting a vibration due to a defect of a magnetic disk to piezoelectric element and the like and has high abrasion resistance and a long service life. The glide head is resiliently held at an end of a suspension arm through a flexure and has a slider, a load point of which a pressing force from the suspension arm is applied to through a pivot disposed on the flexure. The slider comprises two sliding rails that protrude from a bottom surface of the slider, extend from a leading end of the slider to a trailing end of the slider, parallel to and at a distance from each other, and have near the trailing end of the slider a rear edge that works as a sensor for detecting the defect of the magnetic disk.

Abstract: To make is possible to perform communication adapted to changes in a communication environment, a wireless communication device comprises a wireless communication unit for performing communication with another communication device through a wireless communication network, a communication quality evaluation unit for generating an evaluation value with regards to a communication quality of the communication, a communication mode switch unit for switching communication modes for use in the communication according to the evaluation value.

Abstract: A voice communication system, which is connected to LAN to which communication terminals are connected and to a public network to which telephones are connected, is provided with a communication server between the LAN and public network having different protocols from each other. The communication server enables a voice communication between a telephone on the public network and a communication terminal connected to the LAN by performing processing similar to that for a voice communication between two communication terminals connected to the LAN. The communication server determines whether an address of the other party inputted by a user is a communication terminal address or a telephone number, and transmits a voice communication request to a communication terminal of the other party when the address is a communication terminal address.

Abstract: A radio communication network system provides a method of managing radio communication base stations and mobile terminals for accomplishing an access to the Internet from a mobile terminal and communications between mobile terminals. A base station management terminal, radio communication base stations, and mobile terminals reference their communication path information created by exchanging their adjacent terminal information and communication path information to ensure their respective communication paths to other terminals. Even if two mobile terminals cannot communicate due to their radiowaves failing to arrive at their destinations, the mobile terminals can provide a communication path for making communications therebetween through a communication line, the radio communication base station, and the base station management terminal.

Abstract: A light beam deflecting device having therein a rotor portion fixed on an outer circumference of a bearing, a polygon mirror stuck and fixed on a supporting section of the rotor portion and an elastic material for pressing and holding the polygon mirror on the supporting section, wherein the rotor portion has a cylindrical portion fixed on the outer circumference of the bearing, the supporting section and a disc-shaped flange portion provided on an end portion of the cylindrical portion, and a clearance is provided between an inner circumference of the cylinder portion on the end portion side where the flange portion is provided and an outer circumference of the bearing.

Abstract: A mobile communication system with a packet switching function which enables sharing of radio resources among mobile stations, wherein a mobile station which has generated a request for communication quality assurance periodically sends a packet for requesting preferential use of a radio channel in order to prevent timeout of the state transition timer, timeout of which would cancel radio channel assignment to the mobile station and bring it into a dormant state if a certain period elapses without transmission or reception of a signal, so that it can remain in the active state and hold the radio channel continuously. In addition, when the mobile station requesting communication quality assurance moves from one cell to another or requests radio channel assignment, the base station controller controls the radio base station so that the mobile station can be assigned a radio channel by sending a priority request packet.

Abstract: On ad hoc networks in which connection relationships among communication terminals constantly change, the processing load increases when authentication is performed each time a connection relationship changes. According to this invention, when communication terminals possess the same common key, mutual authentication is conducted with that common key, and when communication terminals do not possess the same common key, mutual authentication is conducted with a public key. Communication terminals that conducted mutual authentication exchange and retain a common key that they selected and common keys received from other communication terminals. When neither communication terminal possesses a common key at authentication, one terminal creates a common key and distributes it to the other terminal, and when one terminal has a common key it creates that common key and distributes it to the other terminal.

Abstract: In a mobile IP network system including a plurality of radio access networks for connecting with mobile stations via radio links and an IP network connected with a plurality of packet nodes for transferring IP packets, each of the radio access networks has at least one base station controller and at least one radio base station connected to the base station controller. Each of the base station controllers in the radio access network is connected to the plurality of packet nodes to each other via a network and selects one of the plurality of packet nodes in accordance with a state of each mobile station to establish a logical connection to be used in IP packet communication of the mobile station.

Abstract: A voice communication system, which is connected to LAN to which communication terminals are connected and to a public network to which telephones are connected, is provided with a communication server between the LAN and public network having different protocols from each other. The communication server enables a voice communication between a telephone on the public network and a communication terminal connected to the LAN by performing processing similar to that for a voice communication between two communication terminals connected to the LAN. The communication server determines whether an address of the other party inputted by a user is a communication terminal address or a telephone number, and transmits a voice communication request to a communication terminal of the other party when the address is a communication terminal address.

Abstract: An optical deflection device includes a rotor unit having a rotary polygon mirror and a magnet, a dynamic pressure bearing having a rotary bearing member rotatably supporting the rotor unit and a stationary bearing member, and a stator unit having a base member for supporting the stationary bearing member and a magnet coil for driving the rotary unit in cooperation with the magnet. The optical deflection device further includes a stabilizing member for rectifying and stabilizing airflow caused by the rotation of the rotary polygon mirror, which is mounted on the top of the base member in such a way that the stabilizing member is located close to the mirror surface on the outer periphery of the rotary polygon mirror.

Abstract: There is provided a polygon mirror comprising a mirror body shaped in a regular polygon and having circumferential surfaces, a top surface and a bottom surface, a reflection surface formed on each of the circumferential surface, a machining reference surface provided on one of the top and bottom surfaces, machined to form a mirror surface and used as a reference surface for machining the reflection surface on each of the circumferential surfaces and an assembling reference surface provided on one of the top an bottom surfaces, shaped in parallel to the machining reference surface, machined to form a rough surface and used as a reference surface for assembling the polygon mirror. The polygon mirror has a high degree of reliability in terms of stable optical characteristic when a polygon mirror and a flange member are bonded with each other.

Abstract: In a mobile IP network system containing a plurality of radio access networks 2 for connecting with mobile stations 1 via radio links and an IP network 102 connected with a plurality of packet nodes for transferring IP packets, each of the radio access networks has at least one base station controller 7 and at least one radio base station 6 connected to the base station controller. Each of the base station controllers 7 in the radio access network is connected to the plurality of packet nodes to each other via a network 104 and selects one of the plurality of packet nodes in accordance with a state of each mobile station to establish a logical connection to be used in IP packet communication of the mobile station.

Abstract: This invention relates to an optical deflection device capable of obtaining sufficient durability without any positional error of a polygon mirror even when the rotational speed of the polygon mirror increases to 50,000 rpm or more. An optical deflection device includes a base member, a polygon mirror which is formed into a regular polygon and has a reflecting surface on each peripheral end face, a flange member which holds the polygon mirror and rotates with respect to the base member, and a press member which presses the polygon mirror against the flange member. In this optical deflection device, surface roughening is performed for at least one of the holding surface of the flange member which holds the polygon mirror and the held surface of the polygon mirror which is held by the holding surface, and the holding surface and held surface are bonded with an adhesive.

Abstract: A radio communication network system provides a method of managing radio communication base stations and mobile terminals for accomplishing an access to the Internet from a mobile terminal and communications between mobile terminals. A base station management terminal, radio communication base stations, and mobile terminals reference their communication path information created by exchanging their adjacent terminal information and communication path information to ensure their respective communication paths to other terminals. Even if two mobile terminals cannot communicate due to their radiowaves failing to arrive at their destinations, the mobile terminals can provide a communication path for making communications therebetween through a communication line, the radio communication base station, and the base station management terminal.