Today, the Internet has entered thousands of households, and the Internet has become an indispensable thing in our lives. Generally, the most common network devices at home are: optical modems, routers, switches, wifi, but many users cannot easily distinguish them. When you encounter a network failure and call for help, it often takes a long time to solve the problem because you can’t distinguish the equipment.

Let me introduce the concepts and functions of several network devices such as optical modems, routers, switches, and wifi in detail below.

1. Optical modem: Optical modem, also called single-port optical transceiver, is a kind of optical fiber transmission terminal equipment.
The general application scenarios are: user-Ethernet optical modem-optical cable-E1 optical modem-2M cable-central office SDH optical transceiver A-central office SDH optical transceiver B-PDH optical transceiver-E1 to Ethernet protocol conversion-user equipment (Ethernet switch or computer etc).
Note: To realize optical communication, optical modulation and demodulation must be carried out, so optical modem is a key component of optical fiber communication system.

2. Switch: The main purpose is to access the Internet through a network cable, which has the function of expanding the network port. However, everyone dials up the Internet separately, and each uses their own broadband. Everyone has no effect on the Internet, even if other people are downloading, it will also affect their own Internet access. There is no impact, and all computers using the same switch are in the same LAN. The industrial switches and industrial PoE switches we produce actually fall into this category.

3. Router: Like a switch, it can expand the network port and has a virtual dialing function. Computers connected to the Internet through the same router share the same broadband account, and everyone’s Internet access affects each other. For example, if a computer is downloading, other computers on the same router will obviously feel that the Internet speed is very slow. The computers on the same router are also in a local area network. Our industrial 4G routers also belong to this category, and routers are also divided into multiple categories by level.

4. WiFi: is a technology that allows electronic devices to connect to a wireless local area network (WLAN), usually using 2.4G UHF or 5G SHF ISM radio frequency bands. Connecting to a wireless LAN is usually password-protected; but it can also be open, which allows any device within the range of the WLAN to connect. Wi-Fi is a brand of wireless network communication technology, held by the Wi-Fi Alliance, with the purpose of improving the interoperability between wireless network products based on the IEEE 802.11 standard.

Supplement: Some people say that the router can be used as a switch. The method is as follows: Don’t plug the network cable from the optical modem into the WAN port, but plug it into any LAN port. Other things remain unchanged. At this time, the router realizes the function of a switch.