**2.2.3 Accounting solutions**

### **Post-paid billing**

This mode is that user uses services first and then the operator charges according to the usage of the services.

When the user's session is set up, the system generates the accounting start list of this session . During the session, the system generates the accounting interim list at an interval of some time . When the session ends, the system generates the accounting stop list. Here is the figure of its procedure :

Its procedure is mainly about these points :


Fig. 9. Post-paid Billing Accounting Procedure
