A novel robust fault tolerant scheme for hierarchical AAA in mobile networks

In order to avoid the problem caused by single point of failure of the root AAA (authentication, authorization, and accounting) server in hierarchical AAA mobility management (HAMM), a novel robust fault tolerant scheme for hierarchical AAA (RFT-HA) is proposed in Mobile IPv6. In this scheme, the period of detecting the root AAA server's (RAAAS) failure is decreased by adopting ICMPv6 and Diameter protocol. Furthermore, the procedure of recovering from the RAAAS's failure state is accelerated by using backup binding information. The performance of RFT-HA has been theoretically analyzed. As the consequence, the simulation results show that its performance is better than any other manners in terms of RAAAS's reliability, packet loss rate, and the period of discovery and recovery of RAAAS's failure in hierarchical AAA.