option 2 in 5g
"option 2" typically refers to the 5G radio access network (RAN) architecture defined by the 3rd Generation Partnership Project (3GPP). The 3GPP is a collaboration between telecommunications standards organizations that develops protocols for mobile telecommunications.
The 5G architecture is designed to provide higher data rates, lower latency, improved reliability, and increased capacity compared to previous generations (3G and 4G/LTE). Option 2 specifically defines a split architecture between the Central Unit (CU) and Distributed Unit (DU) in the radio access network. Here's a breakdown of the main components:
- Central Unit (CU):
- The CU is responsible for the higher-level processing and management functions in the RAN.
- It includes functions like radio resource management, connection management, and mobility management.
- The CU communicates with the core network (5G core) and manages the overall coordination of radio resources.
- Distributed Unit (DU):
- The DU is located closer to the radio cells and is responsible for lower-level processing and control functions.
- It handles tasks such as radio transmission and reception, signal processing, and channel coding.
- The DU communicates with the user equipment (UE) and manages the radio interfaces.
- Front Haul:
- The connection between the CU and DU is known as the front haul. It carries the digitized and encoded radio signals between the central and distributed units.
- Front haul connectivity is typically based on optical fiber to provide the necessary capacity and low latency.
- Mid Haul:
- In some architectures, there may be a mid-haul segment between the CU and the 5G core network. This segment is responsible for transporting user and control plane data between the RAN and the core network.
- User Equipment (UE):
- The UE refers to the end-user device, such as a smartphone or other 5G-enabled device.