Network apparatus, edge router, and packet communication system

An edge router comprising:

• an edge router table for storing a transmission destination address of one or more packets and an identifier of a destination-edge router corresponding to the transmission destination address;
• a queue per destination-edge router;
• a slot reservation table for storing a record including an identifier of a time slot witch is assigned to packet transmission destined for a particular destination-edge router, an identifier of an output interface which is used for the packet transmission, and an identifier of the queue corresponding to the particular destination-edge router;
• packet receiving means for receiving the packets from an external network;
• packet classifying means for specifying, from the edge router table, the destination-edge router corresponding to the transmission destination address of the received packets, and for storing the received packets in the queue corresponding to the specified destination-edge router;
• and
• scheduling means for, when switching-over to a particular time slot is detected, specifying the output interface and the queue, which correspond to the particular time slot, from the slot reservation table, transmitting a first control packet, which includes an identifier of the particular time slot and indicates a start of the particular time slot, through the specified output interface, successively transmitting the packets read out from the specified queue after transmitting the first control packet, and for transmitting, as a final packet in the particular time slot, a second control packet which includes the identifier of the particular time slot and indicates an end of the particular time slot.

A packet communication system comprising:

• edge routers each performing packet communication while a time slot is synchronized by using definition information and sync time information of the time slot;
• a network apparatus for relaying one or more packets communicated between the edge routers;
• and
• a management server for delivering the definition information and the sync time information of the time slot to each of the edge routers,
• each of the edge routers comprising:
• an edge router table for storing a transmission destination address of the packets and an identifier of a destination-edge router corresponding to the transmission destination address;
• a queue per destination-edge router;
• a slot reservation table for storing an identifier of a time slot witch is assigned to packet transmission destined for a particular destination-edge router, an identifier of a first output interface which is used for the packet transmission, and an identifier of the queue corresponding to the particular destination-edge router;
• means for receiving the packets from an external network;
• means for specifying, from the edge router table, the destination-edge router corresponding to the transmission destination address of the received packets, and for storing the received packets in the queue corresponding to the specified destination-edge router;
• and
• means for, when switching-over to a particular time slot is detected in a sequential flow of time slots, which is determined based on definition information of each time slot, specifying the first output interface and the queue, which correspond to the particular time slot, from the slot reservation table, transmitting a first control packet, which includes an identifier of the particular time slot and indicates a start of the particular time slot, through the specified first output interface, successively transmitting the packets read out from the specified queue after transmitting the first control packet, and for transmitting, as a final packet in the particular time slot, a second control packet which includes the identifier of the particular time slot and indicates an end of the particular time slot,
• the network apparatus comprising:
• a slot table for storing an identifier of the particular time slot and respective identifiers of an input interface and a second output interface which are used for the packet transmission in the particular time slot;
• and
• means for, when the first control packet is received, specifying from the slot table the input interface and the second output interface corresponding to the identifier of the particular time slot, which is included in the first control packet, and for sending out the packets from the specified input interface to the specified output interface during a period until the second control packet is received.