What is the difference between an ONU, a router and a switch?
What is the difference between an ONU, a router and a switch?
The EPON OLT is a device serving as the endpoint for the service provider in a passive optical network. In other words, the Optical Line Terminal (OLT) manages the Ethernet Passive Optical Network (EPON). This technology offers multiple services thanks to its point-to-multipoint passive optical transmission.
Part I. What are ONU, router and switch?
1. UN
ONU (Optical Network Unit) is also called optical modem, which is a device similar to baseband modem. But the difference is that the UN accesses optical fiber. It converts the digital signal into analog signal by modulation at the transmitting end and transmits the analog signal into digital signal.
Electronic signals are divided into analog and digital signals. Telephone transmission adopts analog signals and PCs transmit digital signals. Therefore, the ONU is used to modulate the signals if the computer connects to the Internet through the telephone line.
2. Router
The router is a gateway that connects two or more networks, which can read the address in each packet and decide how to forward it. The router can understand different protocols such as the Ethernet protocol used by local networks or the TCP/IP protocol used by the Internet. Thus, the router can convert addresses from non-TCP/IP networks to TCP/IP addresses by analyzing the destination addresses of packets coming from different networks. Then it sends the packets to the designated location based on the best route chosen. Thus, the router can connect non-TCP/IP networks to the Internet.
3. Switch
Switch is a device used to transmit electronic or optical signals. It is capable of providing an exclusive electrical signal path for any two network nodes of the access switch. There are Ethernet switch, voice telephone switch, fiber optic switch, etc.
Part II. The difference between ONU, router and switch
Although ONU, router and switch are used for the Internet, there are different applications. Generally, the analog signal transmitted by the network cable is converted into digital signal by the ONU. Then the router transmits the signal to the PC. When the number of PCs exceeds the number of routers that can connect, a switch must be added to extend the interface.
– ONU is generally applied in FTTH. It mainly helps the computer connect to the Internet by converting the signal from the telephone line to that of the network cable.
– The router operates on the network layer of the LAN. He can access the Internet through virtual access using a cable connected to several computers. All computers share a single broadband account, so the Internet affects each other.
– The switch allows simultaneous access to the Internet by connecting multiple computers with one cable. Each computer has its own broadband account, so there is no influence between them.
