Also known as Industrial Ethernet Switch, which is an Ethernet switch device used in industrial control. Due to the adopted network standard, it is open, widely used, and inexpensive. It uses a transparent and unified TCP/IP protocol. The network has become the main communication standard in the field of industrial control.
Industrial switches feature carrier-grade performance to withstand harsh environments. With a wide range of products and flexible port configurations, it can meet the needs of various industrial fields. The product features a wide temperature design with a protection rating of no less than IP30 and supports standard and proprietary ring redundancy protocols.
Introduction
There is no essential difference between the data network layer and the network layer and the protocol layer. However, for the real-time requirements of industrial control, Industrial Ethernet solves the real-time communication, network security, intrinsic safety and security explosion-proof. Technical issues such as technology, and the use of some measures suitable for industrial environments, such as waterproof, anti-vibration… The core is not essentially different from commercial Ethernet, which is the same as the difference between PC and IPC.
Networking Structure
Industrial Ethernet switches are specifically designed to meet the needs of flexible industrial applications, providing a cost-effective industrial Ethernet communications solution. The networking method focuses more on loop design. There are single-ring and multi-ring differences in the loop. There are also private loop protocols designed by various vendors based on STP and RSTP, such as RingOn, RingOpen open loop, FRP ring, and turbo ring.
The development of hubs has resulted in a device called an unmanaged switch. It enables routing of messages from one port to another, making them more intelligent than hubs. Unmanaged switches automatically detect the network speed of each network device. In addition, it has a function called “MAC Address Table” that identifies and remembers devices on the network. In other words, if port 2 receives a message with a specific identification code, then the switch will send all messages with that particular identification code to port 2. This intelligence avoids message collisions and improves transmission performance, a huge improvement over hubs. However, unmanaged switches cannot implement any form of communication detection and redundancy configuration.
The next generation of Ethernet connected devices is the managed switch. Managed switches have more and more complex functions than hubs and unmanaged switches, and are much more expensive—typically three to four times as large as an unmanaged switch. Managed switches provide more functionality and are typically fully configured through a network-based interface. It can automatically interact with network devices, and users can manually configure network speed and flow control for each port. Some old devices may not be able to use the automatic interaction feature, so manual configuration is indispensable.
Most managed switches also typically provide advanced features such as SNMP for remote monitoring and configuration (Simple Network Management Protocol), port mapping for diagnostics, VLANs for network device grouping (Virtual Local Area Network), The priority ranking function for ensuring the passage of priority messages, and so on. With a managed switch, you can set up a redundant network. With a ring topology, managed switches can form a ring network. Each managed switch can automatically determine the optimal transmission path and the alternate path, and automatically block the alternate path when the priority path is interrupted.
Managed switches can be managed in several ways: through RS-232 serial port (or parallel port) management, through web browser management, and through network management software management.
1. Management through serial port
The network management switch comes with a serial cable for switch management. First plug one end of the serial cable into the serial port on the back of the switch, and the other end is plugged into the serial port of the ordinary computer. Then power on the switch and computer. The “HyperTerminal” program is available in both Windows 98 and Windows 2000. Open “HyperTerminal”. After setting the connection parameters, you can interact with the switch through the serial cable, as shown in Figure 1. This method does not occupy the bandwidth of the switch, so it is called “Out of band”.
In this management mode, the switch provides a menu-driven console interface or command line interface. You can use the “Tab” or arrow keys to move through menus and submenus, press Enter to execute the appropriate commands, or use a dedicated switch management command set to manage the switch. The command set of different brands of switches is different, even the switches of the same brand, the commands are different. Using menu commands is more convenient in operation.
2. Management through the web
The managed switch can be managed via the Web (web browser), but the switch must be assigned an IP address. This IP address has no other use than the management switch. By default, the switch does not have an IP address. You must enable an IP address through the serial port or other means to enable this management mode.
When using a web browser to manage the switch, the switch is equivalent to a web server, but the web page is not stored in the hard disk, but in the NVRAM of the switch, the web program in the NVRAM can be upgraded by the program. When the administrator enters the IP address of the switch in the browser, the switch passes the web page to the computer just like a server. At this point, it feels like you are visiting a website, as shown in Figure 2. This way takes up the bandwidth of the switch, so it is called “in band”.
If you want to manage the switch, just click on the corresponding function item in the web page and change the parameters of the switch in the text box or drop-down list. Web management can be done on the LAN, so remote management can be achieved.
3. Managed by network management software
The network management switches all follow the SNMP protocol (Simple Network Management Protocol), which is a set of network equipment management specifications that conform to international standards. Any device that complies with the SNMP protocol can be managed by the network management software. You only need to install a set of SNMP network management software on a network management workstation, which can easily manage switches, routers, servers, etc. on the network through the LAN. The interface through the SNMP network management software is shown in Figure 3. It is also an in-band management method.
The management of the network management switch can be managed in the above three ways. Which way is it used? In the initial setting of the switch, it is often necessary to pass out-of-band management; after setting the IP address, you can use the in-band management mode. In-band management Because management data is transmitted over a publicly used LAN, remote management can be achieved, but security is not strong. Out-of-band management is communicated through the serial port. Data is only transmitted between the switch and the management machine, so the security is very strong; however, due to the limitation of the serial cable length, remote management cannot be realized. So which way to look at your requirements for security and manageability.
Industrial switches are widely used in industrial applications, mainly in coal mine safety, rail transit, factory automation, water treatment systems, and urban security.
The difference between industrial switches and commercial switches
The difference between an industrial Ethernet switch and a commercial switch is mainly reflected in the function and performance.
The difference in function mainly refers to the fact that industrial Ethernet switches are functionally closer to industrial network communication, such as interconnection with various fieldbuses, redundancy of devices, and real-time of devices;
The difference in performance is mainly reflected in the adaptation to the external environmental parameters. In addition to many harsh environments such as coal mines and ships, the industrial environment has special requirements for EMI (electromagnetic compatibility), temperature, humidity, and dust. Among them, the temperature has the most extensive influence on industrial network equipment.
- Components: Industrial Ethernet switch components have higher requirements for selection and should be better adapted to the needs of industrial production sites.
- Mechanical environment: Industrial Ethernet switches can better adapt to harsh mechanical environments, including vibration, shock, corrosion, dust, and water.
- Climate: Industrial Ethernet switches are better suited to poorer climates, including temperature and humidity.
- Electromagnetic environment: Industrial Ethernet switches have strong anti-electromagnetic interference capabilities.
- Operating voltage: Industrial Ethernet switches have a wide operating voltage range, and commercial switches require higher voltages.
- Power supply design: Commercial switches are basically single-supply, while industrial switch power supplies are generally dual-power backups.
- Installation method: Industrial Ethernet switches can be installed in DIN rails and racks. Commercial switches are generally rack and desktop.
- Cooling method: Industrial Ethernet switches generally use a fanless enclosure for heat dissipation, while commercial switches are fan-distributed.
Original article from: https://www.optcore.net/
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