What are distributed units (DUs) in Cloud RAN?

Distributed Units (DUs) in a Cloud RAN architecture are specifically designed to handle real-time processing tasks related to the access network. They play a critical role in executing time-sensitive functions required for radio processing, including signal encoding and decoding, control signaling, and other essential tasks that demand low latency and quick response times.

DUs work in conjunction with Central Units (CUs) to distribute the workload efficiently, ensuring that the processing requirements of the radio interface can be met. This separation allows for greater flexibility and scalability within the network, optimizing performance and operational efficiency. By performing the real-time processing closer to the radio units, DUs can meet the demands of high-speed data transmission and the responsiveness required for applications such as voice over LTE (VoLTE) and other latency-sensitive services.

In contrast, components that manage user authentication, store user data, or interface with external networks do not specifically pertain to the role of DUs in the Cloud RAN framework. Such functions are typically handled by other elements within the network architecture, highlighting the specialized nature of DUs in focusing on real-time processing tasks.