Abstract: Estimation is carried out with high accuracy based on flow quality information in a situation where, although a set of links that may have a flow passing through is known, which of such links the flow passed through cannot be identified, such as multi-paths routing, load distribution routing, and the like.

Abstract: A processing capability for data communication with a packet terminal is secured while packet loss is prevented, and a load to a mobile station in a handover is reduced. A wireless communication system comprises mobile stations 101 and 102 each having a wireless interface a configured with an antenna 11a and a wireless transmission/reception unit 12a as well as a wireless interface b configured with an antenna 11b and a wireless transmission/reception unit 12b, MAC addresses being assigned to the wireless interfaces, and base stations 201 and 202 for performing data transfer with the mobile stations 101 and 102, a L2SW 302 for switching base stations that performs the data transfer, and a packet terminal 401 for performing the data communication with the mobile stations 101 and 102. When the mobile stations 101 and 102 perform the handover, a data transfer MAC address assigned to the wireless interface (one of a and b) is reassigned to the other wireless interface.

Abstract: To provide a data communication system which lightens processing related to changes in the status in signaling processing performed between terminals. A signaling server communicating mutually with a plurality of terminals includes: a transmitting/receiving part for transmitting/receiving a message; a status management part for updating a registered terminal list and status management information; and a signaling processing part for judging a destination and a type of the message received at the transmitting/receiving part. The signaling processing part gives an instruction to the status management part to update the status management information in accordance with contents of the message without transferring the message to a first terminal, when the first terminal requires the signaling processing support and the message is not directly related to starting or stopping of communication with the first terminal.

Abstract: An external network relay device measures group movement parameters that are used to determine whether the need exists to change the group affiliation of internal network relay devices. When the results of measuring the group movement parameters meet conditions that have been set in advance, the external network relay device transmits group movement notification messages instructing group movement to the internal network relay devices of its own group and causes the internal network relay devices to change to other groups.

Abstract: To provide a data communication system which lightens processing related to changes in the status in signaling processing performed between terminals. A signaling server communicating mutually with a plurality of terminals includes: a transmitting/receiving part for transmitting/receiving a message; a status management part for updating a registered terminal list and status management information; and a signaling processing part for judging a destination and a type of the message received at the transmitting/receiving part. The signaling processing part gives an instruction to the status management part to update the status management information in accordance with contents of the message without transferring the message to a first terminal, when the first terminal requires the signaling processing support and the message is not directly related to starting or stopping of communication with the first terminal.

Abstract: In order to provide a data communication system that reduces a data amount of messages, a simple catalog identifier 31 is assigned to a plurality of common parameters. Each of terminals or servers replaces the common parameters by the simple and identical catalog identifier and transmits the simple catalog identifier to other terminals or servers.

Abstract: Estimation is carried out with high accuracy based on flow quality information in a situation where, although a set of links that may have a flow passing through is known, which of such links the flow passed through cannot be identified, such as multi-paths routing, load distribution routing, and the like.

Abstract: A processing capability for data communication with a packet terminal is secured while packet loss is prevented, and a load to a mobile station in a handover is reduced. A wireless communication system comprises mobile stations 101 and 102 each having a wireless interface a configured with an antenna 11a and a wireless transmission/reception unit 12a as well as a wireless interface b configured with an antenna 11b and a wireless transmission/reception unit 12b, MAC addresses being assigned to the wireless interfaces, and base stations 201 and 202 for performing data transfer with the mobile stations 101 and 102, a L2SW 302 for switching base stations that performs the data transfer, and a packet terminal 401 for performing the data communication with the mobile stations 101 and 102. When the mobile stations 101 and 102 perform the handover, a data transfer MAC address assigned to the wireless interface (one of a and b) is reassigned to the other wireless interface.

Abstract: A mobile station for communicating with a plurality of base stations, including: a field strength detecting circuit that detects a wave strength received from the base stations and outputs a received wave strength; and a base station switching control circuit that makes a comparison between the received wave strength and a first field strength threshold level, wherein, when the received wave strength is higher than the first field strength threshold level, data communication with one of the base stations which is in a connected state is performed, and when the received wave strength is lower than the first field strength threshold level, a search for base stations is performed.

Abstract: A communication-quality monitoring system includes a receiving unit for receiving packets to detect packets of a traffic, a frequency-distribution calculator for calculating frequency distribution of the arrival times of the received packets, and a degradation detection unit for detecting degradation of communication quality in the network by comparing statistic parameters of the peak in the frequency distribution against thresholds of the parameters. The parameters include a dispersion, standard deviation, half-power breadth and peak power of the peak in the distribution diagram.

Abstract: A method for detecting an unauthorized or illicit traffic through a network comprises the steps of storing the expected values of a behavior for each type of the traffic in advance, separating individual traffics when performing communications through the network, measuring the behavior of the individually separated traffic, comparing the measured behavior with the expected values of the behavior, and determining the unauthorized or illicit traffic from the measured result.

Abstract: An external network relay device measures group movement parameters that are used to determine whether the need exists to change the group affiliation of internal network relay devices. When the results of measuring the group movement parameters meet conditions that have been set in advance, the external network relay device transmits group movement notification messages instructing group movement to the internal network relay devices of its own group and causes the internal network relay devices to change to other groups.

Abstract: A mobile station for communicating with a plurality of base stations, including: a field strength detecting circuit that detects a wave strength received from the base stations and outputs a received wave strength; and a base station switching control circuit that makes a comparison between the received wave strength and a first field strength threshold level, wherein, when the received wave strength is higher than the first field strength threshold level, data communication with one of the base stations which is in a connected state is performed, and when the received wave strength is lower than the first field strength threshold level, a search for base stations is performed.

Abstract: Horizontal moire phenomenon is reduced by producing a control signal by a moire canceling circuit comprising a frequency divider (1,201,301,401) and a horizontal position shifting circuit (2, 202, 302, 402), and supplying the control signal to a deflection circuit block (3).

Abstract: In a vertical deflection circuit of a display monitor including a vertical deflection coil 41 and a sigmoid correction capacitor 42 connected to the vertical deflection coil 41, a series connection circuit consisting of a resistor 21 and a switch 22 connected in series with each other is connected in parallel with the sigmoid correction capacitor 42. By turning the switch 22 on and off in response to a control signal having a period twice as long as a period of the vertical synchronizing signal, a current flowing through the resistor 21 and the switch 22 is periodically added to a vertical deflection current, thereby causing shift of displaying points on a screen to make the moire phenomenon unnoticeable.

Abstract: A wiring guide bar extending vertically through a protector case and projecting from the upper end thereof is vertically movably supported by an elastic member. In installing a protector cover on the protector case, the elastic member is compressed to locate the upper end of the wiring guide bar below the upper end of the protector case.

Abstract: A phase adjustment circuit for display apparatuses operates to vary the phase of an input sync signal to produce a pseudo sync signal for use in positioning an image at the center of a display screen. The circuit comprises a voltage comparator (50) having two input terminals thereto maintained at the same d.c. voltage, and one input terminal thereto is supplied through a d.c. blocking capacitor (C.sub.2) with a saw-tooth wave signal (P.sub.1) obtained by integrating the input sync signal, whereby a pulse having an edge of its pulse waveform situated always at the midpoint position between the two input sync signals. Pseudo sync signal generation means (101, 102) are triggered by the edge of the pulse waveform so that the pseudo sync signal of a phase different from that of the input sync signal is formed.

Abstract: A television receiver compatible with both American and European systems in which, in the case of switching from the American system mode to the European system mode, the voltage at the center tap of a variable resistor, through which is supplied a tuning voltage, is caused to drop to a lower level so that the tuning voltages for the reception of European system high- and low-band VHF television channels can be obtained.