Diameter
Read this article about the history of Diameter and why it was developed. What preceded Diameter as an authentication protocol? While you do not need to understand how Diameter authenticates, you should have a general idea of its authentication process.
6.Diameter Client API
6.7.Uninitialization API
UnInitialization API used to uninitialize the DIAMETER Client stack which perform deregistration of the stack with TCA, de-allocate the memory allotted for the stack
resources and configuration of the stack.