Abstract: The present invention includes a repeater and a server for controlling access, from a terminal of an outside network, to the server of an inside network. The repeater and the server permit a packet transmission from the terminal to the server under limited conditions. When the server acknowledges a connection for the permitted packet, transmission conditions for packets to be sent to the server are loosened. Subsequently, packet transmission between the terminal and the server is controlled under the loosened transmission conditions. As for encrypted packets, the server decodes the encrypted packets and notifies the repeater of relevant information.

Abstract: A resource management server that manages information concerning the resource reservation status and the information of groups of all electronic equipments connected to hubs. When an electronic equipment is newly connected to a port of one of the hubs, the electronic equipment issues a resource request and the group information to the resource management server. The resource management server sets up a network path between the newly connected electronic equipment and the other electronic equipments belonging to the same group as the newly connected electronic equipment, and judges if the resource request can be accepted on the setup network path.

Abstract: A terminal comprises a packet receiving unit, a packet sending unit, a link-state detecting unit that detects a link-up to a switching device, a configuration-change notifying unit, and a resource reservation table. When the link-state detecting unit detects a link-up, the terminal notifies network configuration information and network resource reservation information to a management device. When a link state is changed, the management device can immediately manage the network based on the latest network configuration information and the latest network resource information.

Abstract: Access points for supporting wireless communications, a packet transmission device, and terminals for handing-over between service areas are provided. An existing terminal is provided with respect to this access point for performing a Quality of Source (QoS) guarantee. Accordingly, when a new terminal is handed over to be engaged in wireless communications with this access point, the priority of the packet associated with the existing terminal and/or new terminal is changed.

Abstract: The communication system supports reservation of network resources. The base stations relay packets among the terminals, and perform priority control based on the priority set to the packets. In the terminal, the communication-managing table stores communication information of own terminal and a partner thereof. The packet-transmitting unit, setting priority to the packets, transmits the packets. When link condition of own terminal change, the link-managing unit updates, in order to prevent from quality deterioration of the other terminals, the priority of each of the packets whose source terminal is the own terminal.

Abstract: Access from a terminal of an outside network to a server of an inside network is put under control. A repeater and the server permit a packet transmission from the terminal to the server under limited conditions. When the server acknowledges connection for the permitted packet, the transmission conditions for packets to be sent to the server are loosened. After then, packet transmission between the terminal and the server is controlled under the loosened transmission conditions. As for encrypted packets, the server decodes the encrypted packets and notifies the relevant information to the repeater.

Abstract: A terminal comprises a packet receiving unit, a packet sending unit, a link-state detecting unit that detects a link-up to a switching device, a configuration-change notifying unit, and a resource reservation table. When the link-state detecting unit detects a link-up, the terminal notifies network configuration information and network resource reservation information to a management device. When a link state is changed, the management device can immediately manage the network based on the latest network configuration information and the latest network resource information.

Abstract: The communication system supports reservation of network resources. The base stations relay packets among the terminals, and perform priority control based on the priority set to the packets. In the terminal, the communication-managing table stores communication information of own terminal and a partner thereof. The packet-transmitting unit, setting priority to the packets, transmits the packets. When link condition of own terminal change, the link-managing unit updates, in order to prevent from quality deterioration of the other terminals, the priority of each of the packets whose source terminal is the own terminal.

Abstract: A method for reserving communication resources in a gang of apparatus that include a terminal “T1” operable to transmit packets, relays “X0” to “X4” operable to relay the packets, and a receiver “T2” operable to receive the packets. The method comprises defining a link for interconnecting respective interfaces of two apparatus selected from the gang of apparatus, defining a path between the transmitter and the receiver as an assembly of the links, checking all of the links that form the path to see how the links are connected together, and reserving the resources in accordance with the content of requested reservation when all of the links that form the path are found connected together in accordance with the content of the requested reservation.

Abstract: The video server provides a service of lower quality than that of the service which a user demanded within the limits of a reservable bandwidth, when a bandwidth required for providing the service which a user has demanded cannot be reserved. Therefore, although quality is lower than the quality which a user demands, a service can be received at least when a user wants to receive the service. Therefore, a user's dissatisfaction can be released, as compared with the case where service is not provided at all.

Abstract: The resource management server manages the information concerning the resource reservation status and the information of groups of all electronic equipments connected to the hubs. When an electronic equipment is newly connected to a port of one of the hubs, the electronic equipment issues a resource request and the group information to the resource management server. The resource management server sets up a network path between the newly connected electronic equipment and the other electronic equipments belonging to the same group as the newly connected electronic equipment, and judges if the resource request can be accepted on the setup network path.

Abstract: Access points for supporting wireless communications, a packet transmission device, and terminals for handing over between service areas are provided and an existing terminal is provided with respect to this access point for performing QoS guarantee, so that when a new terminal is handed over to be engaged in wireless communications with this access point, the priority of the packet associated with the existing terminal and/or new terminal is changed.

Abstract: Each band-pass unit of a second transmitting/receiving apparatus includes a band-pass means and a receiving quality detection means. The respective band-pass means have different passbands. The receiving quality detection means detects receiving quality information of a signal that has passed through the band-pass means. A receiving quality control means generates a receiving quality control signal based on the receiving quality information. The receiving quality control signal is a signal which becomes a basis for controlling the electric energy level of a signal transmitted by a first transmitting/receiving apparatus. The first transmitting/receiving apparatus adjusts the level of the signal transmitted in each passband.