What is DIAMETER?
Diameter is a planned replacement of RADIUS. It is an AAA protocol for applications such as network access and IP mobility. Listed below are a few points that you need to know about Diameter:
It is intended to work in both local and roaming AAA situations.
Diameter is just twice the predecessor protocol Radius.
It uses TCP or SCTP and not UDP.
It uses transport level security (IPSEC or TLS).
It has 32 bit identifier instead of 8 bit.
It supports stateless as well as stateful mode.
It supports application layer acknowledgement, define failover.
It offers better roaming support.
It uses AVPs.
Diameter allows to define new commands and attributes. It is easy to extend.
What is Next?
Now you have a basic understanding of Radius and Diameter. To gain more knowledge about these protocols, you need to go through various RFCs and other resources mentioned in the Resources section.