Abstract: A network apparatus which is one of two network apparatuses using a tunneling protocol and which accommodates a user, wherein the network apparatus includes a function for uniquely determining an identifier in a header of the tunneling protocol in accordance with a setting made by a network operation administrator, and encapsulating and transmitting a packet with the determined identifier, and the other network apparatuses connected to the DPI apparatus 10 includes a function of carrying out decapsulation processing, converting the identifier in the tunneling protocol header into an identifier associated with the output destination interface, attaching a conversion result to a decapsulated packet as an internal control tag, and transferring the conversion result to hardware carrying out packet transfer processing.

Abstract: A Provider Edge PE3 replicates a received packet and relays these to virtual circuits VC1, VC2 respectively, and Provider Edges PE2, PE2 respectively receive the packets from the virtual circuits VC1, VC2, whereupon the Provider Edges PE2, PE2, on the basis of an agreement between them, decide to handle the received packets such that one of the first edges relays the packet to a Customer Edge CE1 for forwarding to a Host A, while the other edge discards the packet without relaying it to the Customer Edge CE1.

Abstract: In a ring network including an old master node 100, a new master node 110 is used as a replacement for the old master node 110. During replacement operation, when detecting that two ring ports of the new master node 110 are set in link-up state, the new master node 110 gives a transit node 200 an instruction to forward a health check frame H102 sent from a ring port 102 of the old master node 100 by a forwarding route going through the new master node 110. The new master node 110 can monitor the status of the ring network by receiving the health check frame H102. This configuration enables continuous monitoring for a failure occurring in the ring network during replacement of the master node.

Abstract: In a ring network including an old master node 100, a new master node 110 is used as a replacement for the old master node 110. During replacement operation, when detecting that two ring ports of the new master node 110 are set in link-up state, the new master node 110 gives a transit node 200 an instruction to forward a health check frame H102 sent from a ring port 102 of the old master node 100 by a forwarding route going through the new master node 110. The new master node 110 can monitor the status of the ring network by receiving the health check frame H102. This configuration enables continuous monitoring for a failure occurring in the ring network during replacement of the master node.

Abstract: When the provider edge PE1 detects the occurrence of a failure at the access line AL1, it sends the label withdraw message to the virtual circuit VC1, and when the provider edge PE2 receives the label withdraw message sent via the virtual circuit VC1, the access line AL2 is put to a link down state, and when the customer edge CE2 detects the link down state of the access line AL2, it switches from the normal path to the redundant path.

Abstract: A Provider Edge PE3 replicates a received packet and relays these to virtual circuits VC1, VC2 respectively, and Provider Edges PE2, PE2 respectively receive the packets from the virtual circuits VC1, VC2, whereupon the Provider Edges PE2, PE2, on the basis of an agreement between them, decide to handle the received packets such that one of the first edges relays the packet to a Customer Edge CE1 for forwarding to a Host A, while the other edge discards the packet without relaying it to the Customer Edge CE1.

Abstract: A Provider Edge PE3 replicates a received packet and relays these to virtual circuits VC1, VC2 respectively, and Provider Edges PE2, PE2 respectively receive the packets from the virtual circuits VC1, VC2, whereupon the Provider Edges PE2, PE2, on the basis of an agreement between them, decide to handle the received packets such that one of the first edges relays the packet to a Customer Edge CE1 for forwarding to a Host A, while the other edge discards the packet without relaying it to the Customer Edge CE1.

Abstract: A network relay system includes a plurality of internal network relay devices. The network relay system learns multiple pieces of route information to an external network, creates a plurality of allocation route tables designed to allocate the learnt multiple pieces of route information to the internal network relay devices. The network relay system then generates address space information showing a correlation of IP address ranges on an IP address space between the allocation route tables and respectively registers the allocation route tables, along with the generated address space information, in the internal network relay devices. Each of the internal network relay devices transfers a data frame, based on the address space information and the allocation route table registered in the self-device.

Abstract: A Provider Edge PE3 replicates a received packet and relays these to virtual circuits VC1, VC2 respectively, and Provider Edges PE2, PE2 respectively receive the packets from the virtual circuits VC1, VC2, whereupon the Provider Edges PE2, PE2, on the basis of an agreement between them, decide to handle the received packets such that one of the first edges relays the packet to a Customer Edge CE1 for forwarding to a Host A, while the other edge discards the packet without relaying it to the Customer Edge CE1.

Abstract: A Provider Edge PE3 replicates a received packet and relays these to virtual circuits VC1, VC2 respectively, and Provider Edges PE2, PE2 respectively receive the packets from the virtual circuits VC1, VC2, whereupon the Provider Edges PE2, PE2, on the basis of an agreement between them, decide to handle the received packets such that one of the edges relays the packet to a Customer Edge CE1 for forwarding to a Host A, while the other edge discards the packet without relaying it to the Customer Edge CE1.

Abstract: A Provider Edge PE3 replicates a received packet and relays these to virtual circuits VC1, VC2 respectively, and Provider Edges PE2, PE2 respectively receive the packets from the virtual circuits VC1, VC2, whereupon the Provider Edges PE2, PE2, on the basis of an agreement between them, decide to handle the received packets such that one of the edges relays the packet to a Customer Edge CE1 for forwarding to a Host A, while the other edge discards the packet without relaying it to the Customer Edge CE1.

Abstract: When the provider edge PE1 detects the occurrence of a failure at the access line AL1, it sends the label withdraw message to the virtual circuit VC1, and when the provider edge PE2 receives the label withdraw message sent via the virtual circuit VC1, the access line AL2 is put to a link down state, and when the customer edge CE2 detects the link down state of the access line AL2, it switches from the normal path to the redundant path.