Abstract: A backup system of a ring network and a backup method of a ring network are provided. The backup system of a ring network includes a plurality of switches. Each switch includes two main connection ports and two redundant connection ports. One of the two main connection ports of each switch is connected to one of the two main connection ports of an adjacent switch via a main link, and one of the two redundant connection ports of each switch is connected to one of the redundant connection ports of an adjacent switch via a redundant link. The main links are preset to be in a work state, and the redundant links are preset to be in a backup state. When one of the main links is faulty, the redundant link corresponding to the faulty main link is converted to be in the work state.

Abstract: Disclosed is a network-connection redundant system for devices with cascade networking capability, and a method applied on the system. Every device capable of network connection preferably has two network ports, which are respectively connected to the same or different network nodes. The route of network packets can be controlled by defining the roles of ports. One emergent redundant connection is achieved. According to the preferred embodiment, every port is defined as one role such as forward port or blocked port after the network formed by the nodes and devices is initialized. It is featured that a plurality of connection-confirmation packets periodically transmitted or received by the network nodes are used to determine whether state of the connection changes or not. If there is any change, the role for each port is re-defined based on the relevant information. A redundant connection is then established.

Abstract: Disclosed are an expandable network system and a redundant method applied to the system. According to one embodiment, the network system may be a ring-type or linear-type network system. A plurality of network nodes form one or more sub-networks. Many interconnected sub-networks form another network. While the network system is initialized, the method defines the role of each network port of each network node in each sub-network. Concurrently, every network port interconnected between the sub-networks is also defined to be a blocked port or a forward port. This mechanism defining the role of each port not only prevents the possible broadcast storm occurred in the network system, but also modifies the network signaling path by re-defining the roles of the ports while the connection changes. Therefore, the expandable network system and the method achieve a fast-redundant connection scheme, and the more flexible network-expanding function.

Abstract: Disclosed are an expandable network system and a redundant method applied to the system. According to one embodiment, the network system may be a ring-type or linear-type network system. A plurality of network nodes form one or more sub-networks. Many interconnected sub-networks form another network. While the network system is initialized, the method defines the role of each network port of each network node in each sub-network. Concurrently, every network port interconnected between the sub-networks is also defined to be a blocked port or a forward port. This mechanism defining the role of each port not only prevents the possible broadcast storm occurred in the network system, but also modifies the network signaling path by re-defining the roles of the ports while the connection changes. Therefore, the expandable network system and the method achieve a fast-redundant connection scheme, and the more flexible network-expanding function.

Abstract: Disclosed is a network-connection redundant system for devices with cascade networking capability, and a method applied on the system. Every device capable of network connection preferably has two network ports, which are respectively connected to the same or different network nodes. The route of network packets can be controlled by defining the roles of ports. One emergent redundant connection is achieved. According to the preferred embodiment, every port is defined as one role such as forward port or blocked port after the network formed by the nodes and devices is initialized. It is featured that a plurality of connection-confirmation packets periodically transmitted or received by the network nodes are used to determine whether state of the connection changes or not. If there is any change, the role for each port is re-defined based on the relevant information. A redundant connection is then established.

Abstract: A ring network redundancy method is disclosed. If somewhere the connection of the ring network is damaged and broken, then the state of an initially blocked port that has been assigned as blocked is set as forward so as to keep the network functioning. And after the problem is repaired, a newly assigned blocked port is then assigned so that there is now once more a blocked ported; wherein the position of this newly assigned blocked port is set directly at one of the two ends of the repaired network line. Thereby the resettling time for the position of the newly assigned blocked port is reduced, thus the ring network system becomes much more stable.

Abstract: A ring network redundancy method is disclosed. If somewhere the connection of the ring network is damaged and broken, then the state of an initially blocked port that has been assigned as blocked is set as forward so as to keep the network functioning. And after the problem is repaired, a newly assigned blocked port is then assigned so that there is now once more a blocked ported; wherein the position of this newly assigned blocked port is set directly at one of the two ends of the repaired network line. Thereby the resettling time for the position of the newly assigned blocked port is reduced, thus the ring network system becomes much more stable.