How To Purchase Industrial Network Switches?

Industrial network switch, also known as Industrial Switch. That is, Ethernet switch equipment applied to industrial control field, which is widely used, mainly in: coal mine safety, rail transit, factory automation, water treatment system, urban security, etc. Nowadays, there are many brands of industrial network switches in the market. How to choose a suitable industrial network switch is a headache, because many factors need to be considered, such as working environment, whether redundancy is required, network management and non network management, future maintenance and scalability, etc.

What factors should be considered before purchasing industrial network switches?

1. From the perspective of standardization: the selection of industrial network switches should meet the industry specifications, for example, in high-risk situations, products that meet the corresponding certification specifications should be selected; The rail transit industry shall select products recognized by the rail transit industry.

2. From the aspect of working environment: mainly consider temperature and humidity, EMC, protection grade, device method, power supply, etc. Industrial network switches are mainly applicable to extreme environments.

3. Considering the rate of communication service: Industrial network switch ports are divided into 100M, Gigabit and 10 Gigabit. Select appropriate ports according to the service requirements to ensure the broadband carrying service data.

4. Network management type or non network management type: if the network architecture is simple, plug and play unmanaged industrial network switches can be selected; Considering the convenience of subsequent maintenance and management, the managed industrial network switch is a better choice, because only managed switch can achieve redundancy. In short, the managed network switch enables you to configure the network, while the non managed switch can only realize communication between Ethernet devices. Managed switches also enable you to monitor your network. Through the simple network management protocol, you can check various network configurations, packet expansion throughput, network error messages and port configurations.

The managed industrial network switch also has some advanced features that can control the network. Features such as communication quality (QoS), virtual local area network (VLAN), port mirroring, multicast listening IGMP Snooping, redundancy and SNMP are unique to network managed switches.

5. In terms of communication, it is necessary to calculate the number of RJ45 interfaces and optical fiber interfaces required, and consider the problem of capacity expansion.

With the gradual deepening of network applications, industrial network switches have become the focus of today's market competition. However, in the industrial network switch equipment with different functions and various types, users need to get out of the fog and find products that meet their own application characteristics.

For general industrial network switches, simple QoS guarantees, security mechanisms, support for network management policies, spanning tree protocols, and VLANs are all essential functions. However, if carefully analyzed, some functions can be further subdivided under a simple representation. These subdivision functions are the main reasons for product differences and an important way to reflect product added value. In order to provide greater flexibility for users in practical applications, the switch's QoS policy must support multi-level packet priority settings, which can be set for MAC address, VLAN, IP address and port respectively. At the same time, the industrial network switch should also have good congestion control and flow restriction capabilities, support Diffserv differentiated services, and be able to intelligently distinguish different application flows according to the source/destination MAC/IP to meet the needs of real-time multimedia applications.

In addition, the following factors must be considered when purchasing industrial network switches:

1) Real time performance of industrial network switch

In different application environments, the response time and jitter that the system can tolerate are quite different. Data frames in the automation network will have a certain delay in each process of forwarding from one device to another. Therefore, the first thing to consider when selecting an industrial switch is the port delay of the switch in the process of data frame forwarding. In the standard factory automation control system, the system can tolerate a response time of no more than 10 milliseconds. In order to control the cumulative delay of data frames from the top to the bottom of the system, when selecting the switch, it should be noted that the switch port delay should not exceed 10 microseconds.

2) Industrial network switch compatibility

Industrial network switches and other components of industrial Ethernet should be able to communicate using standard TCP/IP protocols. In any case, there should be no incompatibility between industrial switch equipment and commercial Ethernet equipment. Corresponding to different industrial field bus solutions, industrial switch equipment shall have corresponding capabilities compatible with them.

3) Industrial network switch security

Because of the openness of the industrial network switch, we have to consider the factor of network security in the process of building the automation network. When selecting equipment, users should select industrial switches with VLAN function to facilitate the function division of the network. Through VLAN division, we can isolate the devices in the network by groups based on functions to avoid malicious damage or misoperation. At the same time, users can use the 802.1x function of the industrial switch to authorize and license the devices that need to access the network, so as to distinguish between legal users and illegal users.

Therefore, when we choose an industrial network switch, we should first understand the basic professional knowledge of the industrial switch. The expensive one is not necessarily good. On the basis of ensuring the quality of the switch, we should comprehensively consider a variety of factors to choose an industrial network switch with a high cost performance ratio, so that we can work better.