Can Industrial Switches Of Different Manufacturers Form Ring Network Redundancy?

Ring network redundancy is a high-speed Ethernet redundancy technology. This technology can not only ensure that the communication can be recovered within 300 milliseconds (when applied to more than 20 ethernet switches) in case of network failure, but also send an alarm through error relay, indicator light or SNMP when the ring network link is disconnected. Once the ring network is disconnected, the indicator will send an alarm on the disconnected switch, activate its status relay, and feed back the error information to the user through SNMP.

Generally speaking, Ethernet ring redundancy technology can enable another sound communication link when the communication link fails, which greatly improves the reliability of network communication. With the wide application of Ethernet in the field of industrial control, many research institutions at home and abroad have done a lot of work in network redundancy and fault tolerance. Major Industrial Switch manufacturers have also put forward their own network redundancy technology (SW-Ring) solutions to improve the reliability of industrial Ethernet.

As an important data communication product, to ensure the long-term stable and safe operation of the system, the system must be open and compatible with the products of multiple manufacturers. If it only depends on one manufacturer, the risk is great. Therefore, based on the consideration of scalability and compatibility, it is necessary to fully consider the mixed formation of ring network redundancy of industrial switches from different manufacturers, so as to lay a good foundation for future network expansion. So, can industrial switches from different manufacturers form ring network redundancy?

The answer is yes. The industrial switches of different manufacturers can be interconnected through the ring electric port and optical port.

1. Networking protocol

Relevant national standards, national power enterprise standards and industry standards under development clearly stipulate that "networking can be carried out according to the requirements of the power system, and the networking protocol should adopt international standard protocols: RSTP, MSTP, etc.". Therefore, the industrial switch must support RSTP and MSTP international standard ring network protocols in addition to the private ring protocol with independent intellectual property rights developed by various manufacturers. As long as RSTP and MSTP international standard ring network protocols are adopted, industrial switches from different manufacturers can form networks with star, ring, tree and other topological structures.

2. Physical layer

The interconnection and interworking of industrial switches from different manufacturers have no physical problems, as long as the media parameters are consistent, such as whether the industrial media converter is single mode or multimode, and the wavelength parameters of the media converter.

To sum up, no matter from the networking protocol or the physical layer, the industrial switches of different manufacturers can be interconnected when forming the same ring network.

How to form ring network redundancy for industrial switches of different manufacturers

1. The private protocol of an industrial switch manufacturer is used for networking

When industrial switches from different manufacturers form the same ring network, if they use private ring network protocols, they cannot be interconnected. One party needs to change the protocol to adapt to the other party. This adaptation is based on the fact that all private protocols are STP-based and use BPDU messages to realize data transmission in the ring network. Therefore, it is only necessary to modify the format of BPDU. The advantage of this scheme is that there is no need to adjust the equipment in the network. The disadvantage is that the private ring network protocol needs to be provided by the used ethernet switch, and every time a new manufacturer enters, it will have the same problem. Therefore, this scheme is not recommended.

2. Networking with shared protocol

Based on the consideration of future maintenance, upgrade, expansion and reconstruction of industrial Ethernet dedicated for distribution automation, the best solution is to use RSTP protocol to form a network of industrial switches in the whole network, and build a fully open, fully compatible and highly scalable network.

(1) The scheme is simple, effective, one-time treatment, and can benefit for a long time;

(2) The implementation of hybrid networking will comprehensively improve the compatibility of the whole network, improve the ability of system upgrade and update, and thoroughly solve the potential risks due to poor system compatibility, such as the disappearance of manufacturers, industrial adjustment and shutdown, and inadequate technical support;

(3) The research and development of ethernet switch networking protocol is a huge project, which can only be completed by the international standardization organization and the global technical elite. No single company can compete with it. With the development of technology and demand, it is inevitable to upgrade the protocol. Therefore, the scheme adopts international standard protocols, which can well avoid the problem that private protocols cannot be updated and upgraded synchronously.

In short, the industrial redundant ring network is designed to achieve the stability, reliability and real-time performance of data transmission in harsh environments. Its working principle is that the physical connection is in a ring structure, and the network signal is in a chain structure during operation. Once a node of the transmission optical cable breaks, the industrial switch equipment automatically switches to the standby line for transmission in a very short time. Redundant ring network structure not only reduces the risk of data signal transmission, but also simplifies the engineering installation and reduces the engineering cost.