ONU definition
ONU (Optical Network Unit) is called optical network unit and is one of the key devices in the optical fiber access network (FTTH). It is located at the user end and is responsible for converting optical signals into electrical signals and processing the electrical signals into data transmission formats to achieve high-speed data access for users.
XPON 4GE WIFI CATV USB ONU CX51141R07C
1.ONU device functions
The ONU device has the following functions:
Physical function: The ONU device has an optical/electrical conversion function, which can convert the received optical signal into an electrical signal, and at the same time convert the electrical signal into an optical signal for transmission.
Logical function: The ONU device has an aggregation function, which can aggregate the low-speed data streams of multiple users into a high-speed data stream. It also has a protocol conversion function, which can convert the data stream into a suitable protocol format for transmission.
2.ONU protocol
ONU equipment supports multiple protocols, including Ethernet protocol, IP protocol, physical layer protocol, etc., as follows:
Ethernet protocol: ONU equipment supports Ethernet protocol and can realize data encapsulation, transmission and decapsulation.
IP protocol: ONU equipment supports IP protocol and can realize data encapsulation, transmission and decapsulation.
Physical layer protocol: ONU equipment supports a variety of physical layer protocols, such as EPON, GPON, etc., which can realize the transmission and modulation and demodulation of optical signals.
3.ONU registration process
The registration process of ONU equipment includes initial registration, periodic registration, exception handling, etc., as follows:
Initial registration: When the ONU device is powered on and started, it will be initialized and registered through the OLT (Optical Line Terminal) device to complete the self-test and parameter configuration of the device.
Periodic registration: During normal operation, the ONU device will periodically send registration requests to the OLT device to maintain the communication connection with the OLT device.
Exception handling: When the ONU device detects an abnormal situation, such as network failure, link failure, etc., it will send alarm information to the OLT device to facilitate timely troubleshooting.
4.ONU data transmission method
The data transmission methods of ONU equipment include the transmission of analog and digital signals as well as signal modulation and demodulation, as follows:
Analog signal transmission: The ONU device transmits the user's audio, video and other analog data to the user-end device through analog signal transmission.
Digital signal transmission: ONU equipment transmits the user's digital data to the client device through digital signal transmission. Digital signals need to be encoded before transmission. Common encoding methods include ASCII code, binary code, etc.
Signal modulation and demodulation: During the transmission process of digital signals, ONU equipment needs to modulate the digital signals and convert the digital signals into signal formats suitable for transmission in the channel, such as Ethernet data frames. At the same time, the ONU device also needs to demodulate the received signal and convert the signal back to the original digital signal format.
5.Interaction between ONU and OLT
The interaction between ONU equipment and OLT equipment includes data transmission and control number processing, as follows:
Data transmission: Data transmission is carried out between ONU equipment and OLT equipment through optical cables. In the upstream direction, the ONU device sends the user's data to the OLT device; in the downstream direction, the OLT device sends the data to the ONU device.
Control number processing: Synchronous transmission of data is realized between the ONU device and the OLT device through control number processing. Control number information includes clock information, control instructions, etc. After receiving the control number information, the ONU device will perform corresponding operations according to the instructions, such as data sending and receiving, etc.
6.ONU maintenance and management
In order to ensure the normal operation of ONU equipment, maintenance and management are required, as follows:
Troubleshooting: When an ONU device fails, troubleshooting needs to be carried out in a timely manner. Common faults include power supply failure, optical path failure, network failure, etc. Maintenance personnel need to check the status of the equipment in a timely manner, determine the type of fault and repair it.
Parameter adjustment: In order to ensure the performance of the device and the stability of the network, the parameters of the ONU device need to be adjusted. Parameter adjustments include optical power, transmit power, receiving sensitivity, etc. Maintenance personnel need to make adjustments according to the actual situation to ensure the normal operation of the equipment.
Security management: In order to ensure network security, ONU equipment needs to be securely managed. Maintenance personnel need to set the device's operating permissions, management passwords, etc., and change the passwords regularly. At the same time, security risks such as hacker attacks and virus infections need to be guarded against.
By properly configuring and managing the ONU's network firewall and data encryption functions, user network security can be effectively improved and network attacks prevented. While ensuring network security, you also need to pay attention to constantly updating security policies to deal with increasingly complex and ever-changing network threats.
Post time: Sep-21-2023
