Abstract: In an access point device, a controller controls a wired interface communicating on wire with a network switcher accommodating access point devices and a wireless interface communicating wirelessly with a wireless terminal device located in its service area. Services are handed over between the access point devices responsively to the wireless terminal device moving. Access point devices before and after the handover of services are defined as a handover source and a hand over destination, respectively. A hand over at the hand over destination causes a data frame to be generated containing the MAC address of the wireless terminal device as a source address, a broadcast address as a destination address and address information of its own device. A table holds terminal connection information defining the relationship of the MAC address to the IP address of the wireless terminal device. The data frame is transmitted to the network switcher through the wired interface.

Abstract: A wireless LAN includes two interfaces with a transmitter-receiver function and a channel controller. One of the two interfaces employs one communication channel to search for a communication channel being used by a destination communication unit. The channel controller determines a surrounding radio wave condition based on the communication channel obtained by the searching, and controls channel setting so that the respective communication channels of the two interfaces differ from each.

Abstract: An access control device is provided to a wireless device of a network which is constituted with a plurality of wireless devices connecting with one or a plurality of wireless terminals. The access control device includes: a connection severance terminal selection section which, when a bandwidth employed by a wireless communications section exceeds a threshold, selects a terminal whose connection is to be cut off from among the wireless terminals; a connection severance declaration section which, sends a connection severance declaration message to the other wireless terminals, including information about the connection severance terminal; and a forcible severance instruction section which verifies reception, of a message of declaration of acceptance of the connection severance terminal, and causes a forcible severance instruction message for the connection severance terminal.

Abstract: In a wireless network, access points communicate with each other by transmitting and receiving data in first units and with client devices by transmitting and receiving data in second units over wireless links. A first unit encapsulates one or more second units addressed to client devices served by the same access point. Multiple second units encapsulated in a single first unit are transmitted with a single first-unit header. This scheme enables more payload data to be delivered with less overhead than would be required if every second unit were to be encapsulated in a separate first unit.

Abstract: The network switching system is provided with a communication route management table for managing transmission path information of a wireless network including wireless access devices, and a connection device management table for managing, in common on the wireless network, the information on wireless network devices connected to the wireless access devices. The system is further provided with a signal transmitter for referencing the two tables, and generating a signal frame depending on the destination of communication signals received to transmit the signal frame generated. Communication is prevented from being interrupted when communication route information is updated, and from being invaded on a communication route in the network. The network system is more efficiently utilized.

Abstract: A wireless network is connectable to an authentication server. Each access point in the wireless network includes a supplicant processing unit, an authenticator processing unit, and a function selector. When an access point is detected within communication range, the function selector selects either the supplicant processing unit or the authenticator processing unit. The selected unit operates to carry out or mediate an authentication protocol and establish a secure wireless link, protected by a pairwise encryption key, between the two access points. Because every access point can operate as either an authenticator or a supplicant, it is not necessary to invoke the services of a master authenticator. If an encryption key is compromised, the effect is limited and does not force the entire network to be shut down.

Abstract: An access control device is provided to a wireless device of a network which is constituted with a plurality of wireless devices connecting with one or a plurality of wireless terminals. The access control device includes: a connection severance terminal selection section which, when a bandwidth employed by a wireless communications section exceeds a threshold, selects a terminal whose connection is to be cut off from among the wireless terminals; a connection severance declaration section which, sends a connection severance declaration message to the other wireless terminals, including information about the connection severance terminal; and a forcible severance instruction section which verifies reception, of a message of declaration of acceptance of the connection severance terminal, and causes a forcible severance instruction message for the connection severance terminal.

Abstract: A wireless LAN includes two interfaces with a transmitter-receiver function and a channel controller. One of the two interfaces employs one communication channel to search for a communication channel being used by a destination communication unit. The channel controller determines a surrounding radio wave condition based on the communication channel obtained by the searching, and controls channel setting so that the respective communication channels of the two interfaces differ from each.

Abstract: In an access point device, a controller controls a wired interface communicating on wire with a network switcher accommodating access point devices and a wireless interface communicating wirelessly with a wireless terminal device located in its service area. Services are handed over between the access point devices responsively to the wireless terminal device moving. Access point devices before and after the handover of services are defined as a handover source and a hand over destination, respectively. A hand over at the hand over destination causes a data frame to be generated containing the MAC address of the wireless terminal device as a source address, a broadcast address as a destination address and address information of its own device. A table holds terminal connection information defining the relationship of the MAC address to the IP address of the wireless terminal device. The data frame is transmitted to the network switcher through the wired interface.

Abstract: A wireless network is connectable to an authentication server. Each access point in the wireless network includes a supplicant processing unit, an authenticator processing unit, and a function selector. When an access point is detected within communication range, the function selector selects either the supplicant processing unit or the authenticator processing unit. The selected unit operates to carry out or mediate an authentication protocol and establish a secure wireless link, protected by a pairwise encryption key, between the two access points. Because every access point can operate as either an authenticator or a supplicant, it is not necessary to invoke the services of a master authenticator. If an encryption key is compromised, the effect is limited and does not force the entire network to be shut down.

Abstract: In a wireless network, access points communicate with each other by transmitting and receiving data in first units and with client devices by transmitting and receiving data in second units over wireless links. A first unit encapsulates one or more second units addressed to client devices served by the same access point. Multiple second units encapsulated in a single first unit are transmitted with a single first-unit header. This scheme enables more payload data to be delivered with less overhead than would be required if every second unit were to be encapsulated in a separate first unit.

Abstract: An emergency call system includes a position information management device and a position information notification device, wherein the position information management device includes a first management section which manages first terminal information and first position information of a terminal and a first processing section which receives the first terminal information and transmits the first position information to the position information notification device, wherein the position information notification device includes a second management section which manages the first terminal information and first address information of the position information management device and a second processing section which receives the first terminal information from a first device, transmits the first terminal information of the position information management device on the basis of the first address information, receives the first position information from the position information management device, and transmits the first

Abstract: The network switching system is provided with a communication route management table for managing transmission path information of a wireless network including wireless access devices, and a connection device management table for managing, in common on the wireless network, the information on wireless network devices connected to the wireless access devices. The system is further provided with a signal transmitter for referencing the two tables, and generating a signal frame depending on the destination of communication signals received to transmit the signal frame generated. Communication is prevented from being interrupted when communication route information is updated, and from being invaded on a communication route in the network. The network system is more efficiently utilized.