Abstract: A relaying method includes a request packet generation operation generates a request packet for requesting a connectivity check for all communication routes between said receiver and said transmitter, a request packet transmission operation transmits a generated request packet to a relay, a route information addition operation adds information representing the router itself to the received request packet as route information, a request packet forwarding operation forwards the request packet to which said route information has been added to each of all the communication routes between said receiver and said relay, a response packet generation operation has been transcribed, a response packet transmission operation in which said receiver transmits the generated response packet to said transmitter via said relay, a response packet forwarding operation forwards the received response packet to said transmitter, and a route information output operation outputs the route information included in the received response

Abstract: In a network device and a network system structuring a VLAN at the layer 2 level, a starting network device transmits a structuring packet including a port number corresponding to an address of a terminating network device and a single VLAN after having added thereto an address of the starting network device itself and a port number from which the structuring packet is outputted; a relaying network device transmits the structuring packet to which an address of the relaying network device itself, a port number to which the structuring packet has been inputted, and a port number from which the structuring packet is to be outputted are added; and a terminating network device transmits a setup packet in which port numbers are associated with the VLAN for each of the starting and the relaying network device to each of addresses of the starting and the relaying network device.

Abstract: A path switching system can dramatically decrease time required until a transfer path of user data is switched to a detour path when a failure occurred to a system/line constituting the network. In the path switching system, a path is set by a switch device and a plurality of relay devices adjacent to the switch device, and the switch device has a notification processing section notifying information to specify a corresponding relay device to the plurality of other relay devices when a failure of an adjacent relay device or a line failure between adjacent relay devices is detected, and the relay device has a path change processing section canceling information on the path that passes through the relay device detected to have a failure, from the information notified by the notification processing section of the relay device.

Abstract: A method of connecting a line concentrator to other line concentrators in a switching system, wherein a switching unit accommodates the line concentrator is provided. The method includes the steps of analyzing a call received by the switching unit through the line concentrator, and connecting lines that are accommodated by the line concentrator and are connected to the other line concentrators without connecting through the switching unit when the call is detected to be made between the line concentrator and the other line concentrators. Thus, a call can be made to a specific dial number without connecting through the switching unit provided in the switching system. Additionally, a call can also be made by use of another switching unit when a communication path between the switching unit and the line concentrator is overcrowded.

Abstract: A method of controlling affiliation of a remote line-collection device with a plurality of switches connected via a network includes the steps of providing each switch with a backup-storage area in advance in addition to a normal storage area, and transferring control data of the remote line-collection device from the normal storage area of a first switch to the backup-storage area of a second switch when affiliation of the remote line-collection device is changed from the first switch to the second switch.

Abstract: An apparatus and method for permitting temporary use of a telephone number which promptly permit temporary use of a different telephone number without requiring a telephone installation fee. Virtual telephone number notification unit assigns a virtual telephone number to a subscriber terminal at the request of the subscriber terminal, and virtual telephone number registration unit registers the thus-assigned virtual telephone number in association with connection information on the subscriber terminal. In response to call initiation by another subscriber terminal by means of the virtual telephone number, call connection unit refers to the virtual telephone number registration unit to read out the connection information associated with the virtual telephone number and, based on the connection information, connects the calling subscriber terminal to the first-mentioned subscriber terminal.

Abstract: A method of connecting a line concentrator to other line concentrators in a switching system, wherein a switching unit accommodates the line concentrator is provided. The method includes the steps of analyzing a call received by the switching unit through the line concentrator, and connecting lines that are accommodated by the line concentrator and are connected to the other line concentrators without connecting through the switching unit when the call is detected to be made between the line concentrator and the other line concentrators. Thus, a call can be made to a specific dial number without connecting through the switching unit provided in the switching system. Additionally, a call can also be made by use of another switching unit when a communication path between the switching unit and the line concentrator is overcrowded.