Network switch and network architecture for network coupling and backup

A backup network switch, configured in a switch group of a main network, coupled to at least one first subnet of a subnet group through at least one first link, comprising:

• a processing unit, configured to execute a program code;
• and
• a storage unit, coupled to the processing unit, configured to store the program code to instruct the processing unit to execute a network coupling redundancy method, wherein the network coupling redundancy method comprises:
• periodically sending a first control packet comprising a connection status of the at least one first subnet to at least one primary network switch of the switch group;
• in response to sending the first control packet, receiving at least one first acknowledgement (ACK) packet from the at least one primary network switch;
• performing link change according to a first condition;
• and
• in response to receiving a second control packet from the at least one primary network switch, sending a second ACK packet and performing link change according to the second control packet.

A network architecture for network coupling and backup, comprising:

• a plurality of subnets, belonging to a plurality of subnet groups;
• and
• a main network, comprising a plurality of switch groups, wherein each switch group of the plurality of switch groups is coupled to a subnet group of the plurality of subnet groups and comprises:
• at least one primary network switch, coupled to the subnet group, wherein each primary network switch of the at least one primary network switch is coupled to at least one first subnet of the subnet group through at least one first link;
• and
• a backup network switch, coupled to the subnet group through at least one second link;
• wherein the each switch group of the plurality of switch groups is configured to execute a network coupling redundancy method, wherein the network coupling redundancy method comprises:
• sending, by the backup network switch, a first control packet comprising a connection status of the at least one second link periodically;
• in response to receiving the first control packet, the each primary network switch of the at least one primary network switch sending a first acknowledgement (ACK) packet comprising a connection status of the at least one first link;
• performing, by the backup network switch, link change according to a first condition;
• sending, by the at least one primary network switch, a second control packet according to a second condition;
• in response to receiving the second control packet, the backup network switch sending a second ACK packet and performing link change according to the second control packet;
• and
• in response to receiving the second ACK packet, the at least one primary network switch performing link change.