Abstract: An object of the present invention is to provide an edge device, a control method, and a program with which the effects of loop generation can be minimized from the NW operator side while ensuring connection normality with the device of an NW user. An edge device according to the present invention physically closes an access port upon confirmation that the access port has been connected to an external device while the access port is in a physically released state and a DF state is undefined, notifies other edge devices within an EVPN MH configuration that the host device has entered a state in which the host device may become the DF and causes an EVPN function unit to calculate the DF state to be set, physically opens the access port when the calculation result indicates DF, and physically closes the access port when the calculation result indicates BDF.

Abstract: A network device (PE), a network control method and program which can reduce a BUM traffic packet loss even when a time is taken for route recalculation according to a routing protocol due to a malfunction in a network infrastructure are provided. A network device according to the present invention requests each PE connected to the same ES as that of the network device to perform DF reelection on the basis of a redundant PE list from which the network device has been deleted when cease of a BGP session is detected. In addition, the PE requested to perform the DF reelection executes the DF reelection based on the redundant PE list from which the aforementioned PE has been deleted. In the present invention, BUM traffic can be immediately forwarded from a PE that has become a new DF even when a time is taken for route recalculation according to the routing protocol because another PE connected to the same ES is caused to serve as a DF when the BGP session is ceased.

Abstract: An object of the present disclosure is to provide a provider network device, a network system, and a program that shorten a communication disconnection time during redundancy switching in a Single-Active redundant configuration. The provider network device according to the present disclosure notifies a CE that a VLAN, which has been communicating with traffic, is disabled due to setting of a block point or that new traffic communication is enabled due to releasing of the block point. This allows the CE to quickly delete a previously used transfer database and build up a new transfer database, and thus it is possible to shorten a communication disconnection time during redundancy switching.

Abstract: An object of the present invention is to provide an edge device, a control method, and a program with which the effects of loop generation can be minimized from the NW operator side while ensuring connection normality with the device of an NW user. An edge device according to the present invention physically closes an access port upon confirmation that the access port has been connected to an external device while the access port is in a physically released state and a DF state is undefined, notifies other edge devices within an EVPN MH configuration that the host device has entered a state in which the host device may become the DF and causes an EVPN function unit to calculate the DF state to be set, physically opens the access port when the calculation result indicates DF, and physically closes the access port when the calculation result indicates BDF.

Abstract: An object of the present disclosure is to provide a provider network device, a network system, and a program that shorten a communication disconnection time during redundancy switching in a Single-Active redundant configuration. The provider network device according to the present disclosure notifies a CE that a VLAN, which has been communicating with traffic, is disabled due to setting of a block point or that new traffic communication is enabled due to releasing of the block point. This allows the CE to quickly delete a previously used transfer database and build up a new transfer database, and thus it is possible to shorten a communication disconnection time during redundancy switching.

Abstract: A network device (PE), a network control method and program which can reduce a BUM traffic packet loss even when a time is taken for route recalculation according to a routing protocol due to a malfunction in a network infrastructure are provided. A network device according to the present invention requests each PE connected to the same ES as that of the network device to perform DF reelection on the basis of a redundant PE list from which the network device has been deleted when cease of a BGP session is detected. In addition, the PE requested to perform the DF reelection executes the DF reelection based on the redundant PE list from which the aforementioned PE has been deleted. In the present invention, BUM traffic can be immediately forwarded from a PE that has become a new DF even when a time is taken for route recalculation according to the routing protocol because another PE connected to the same ES is caused to serve as a DF when the BGP session is ceased.