Describe the functions of the Charging Function (CHF) in the 5G Core network.

In a telecommunication network, charging functions are responsible for tracking and managing the usage of network resources by subscribers. These functions play a crucial role in billing and revenue management. Below are some of the key aspects of charging functions:

  1. Session Establishment and Termination:
    • Charging functions are involved in the initiation and termination of communication sessions between users and services.
    • They monitor the start and end times of sessions, helping to determine the duration of resource usage.
  2. Resource Usage Tracking:
    • Charging functions keep track of the resources consumed during communication sessions. These resources may include data volume, duration, and other relevant parameters.
  3. Rating and Charging:
    • Charging functions assess the usage data to calculate charges applicable to the subscriber. This involves applying specific rates for different types of services or resource usage.
  4. Real-Time Charging:
    • In real-time charging scenarios, charging functions might provide immediate feedback on the usage costs to both the subscriber and the network operator.
  5. Offline Charging:
    • In offline charging scenarios, charging information is collected and processed periodically, allowing for the creation of detailed billing records for subscribers.
  6. Interface with Policy and Control Functions:
    • Charging functions often interact with policy and control functions to ensure that charging policies are enforced, and subscribers are billed accurately based on the agreed-upon terms.