Abstract: A communication device (1) according to the present disclosure includes: a frame receiving part (11) which receives a frame; a determining part (12) which determines a user identifier and a priority traffic class; a plurality of queues (13) which each hold frames for each user identifier and priority traffic class; a list storage part (15) which stores a gate control list indicating times of a plurality of time slots and open/closed states which are either open states or closed states of a plurality of gates (14), a gate opening/closing part (17) which controls open/closed states of the plurality of gates; and a frame transmitting part (18) which transmits frames held in a queue (13-k) corresponding to a gate (14-k) controlled to be in an open state, in which at least one time slot in the gate control list is a delay guarantee period.

Abstract: An apparatus includes a build plate, a powder application apparatus that applies metal powder onto the build plate to form a powder layer, a beam irradiation apparatus that irradiates the powder layer with an electron beam, and a control unit that controls the powder application apparatus and the beam irradiation apparatus. When the powder layer is preheated by irradiation with the electron beam, the control unit sets a beam size and an irradiation position of the electron beam such that lines of the electron beam do not overlap each other at least at a start of preheating, and controls the beam irradiation apparatus to gradually increase at least one of a beam current and the beam size of the electron beam from the start of preheating to an end of preheating.

Abstract: An object of the present disclosure is to transfer unicast via a boundary apparatus that is geographically close to a user apparatus even in communication from an L2 network to an EVPN and to prevent overlapping distribution of BUM. According to the present disclosure, there is provided a communication system in which a first network and a second network are connected to each other by a plurality of paths, in which, in the plurality of paths, a transfer prevention unit that prevents transfer of a broadcast frame, an unknown unicast frame, and a multicast frame from the second network to the first network is included, and in which a broadcast frame, an unknown unicast frame, and a multicast frame are transferred from the second network to the first network by only a specific path of the plurality of paths.

Abstract: In the flush of an FDB, as the number of user bases increases, more SWs are required to flush, and an influence on another user also increases due to flooding. The lapse of an aging time causes long-time communication interruption depending on network specifications and apparatus settings. In order to complete transmission of a user frame from the base after an accommodation change, it is necessary not only to do work of a communication carrier side but also to enter a user base. The present disclosure is a communication apparatus including a signal reception unit that receives a signal, a signal transmission unit that transmits a signal, and a frame generation unit that generates a control frame for updating a forwarding database (FDB) of a relay network on the basis of FDBs of apparatuses connected to the relay network. The signal transmission unit transmits the control frame generated by the frame generation unit to each of the apparatuses connected to the relay network.

Abstract: An object of the present disclosure is to provide a network system that prevents traffic of frames between networks while connecting the networks to each other via a plurality of boundary devices. The present disclosure is a network device set in a boundary of a first network and connected to a second network different from the first network, the network device discriminating that a frame flowing into the first network from the second network is a broadcast frame, an unknown unicast frame, or a multicast frame and, when a frame flowing out from the first network to the second network is a frame discriminated as the broadcast frame, the unknown unicast frame, or the multicast frame flowing into the first network from the second network, discarding the frame.

Abstract: According to one embodiment, there is provided a communications system that conducts multiplex communications of main signals and at least one sub-signal via redundant routes between a transmission apparatus and a reception apparatus. The transmission apparatus includes a main signal duplication unit configured to duplicate each of the main signals to be communicated via a main signal channel, according to the number of the redundant routes, and a delay unit configured to adjust sending timings of copies of the main signal on the respective redundant routes based on the at least one sub-signal to be communicated via a sub-signal channel and transmit the copies of the main signal to the respective redundant routes.

Abstract: According to one aspect of the disclosure, in a communication apparatus at a transmission end, a packet train that is input is grouped to generate a duplicate packet for each packet group. For each packet group, encoded packets are generated using some packets in a group of duplication source packets and other packets in a group of duplicate packets that do not correspond to the some packets in the group of duplication source packets, and above-described other packets in the duplication source, some packets in the group of duplicate packets that are not used to generate the encoded packets, and the above-described encoded packets are transmitted.

Abstract: The present disclosure enables a user device to connect to a network via a single edge device out of a plurality of existing edge devices without information being communicated between the edge devices and a device that branches signals and provides branched signals to a plurality of edge devices.