Nortel Nortel Bridgewater Systems Current Mobile IPv4 deployments use RADIUS based MIPv4 user authentication and authorization. Diameter Mobile IPv4 Application [RFC4004] offers another method for MIPv4 authentication, authorization, and dynamic mobility security association allocation, e.g. MN-HA SA allocation. Some SDOs are considering the use of Diameter Mobile IPv4 Application to replace RADIUS based mechanism. However, these SDos use a link layer access authentication mechanism, e.g., using an EAP application, to derive the related MIP4 shared keys and security association. This document an overview of these respected architectures and their handling to MIP4 security association and keys derivation and distribution. It presents an analysis of the performance and impact of Diameter MIPv4 Application and RADIUS based solutions on the time the mobile node uses during the initial session setup. Some common MIPv4 scenarios which require the mobile node to retransmit its initial RRQ message have been identified and used. The set of assumptions and requirements used for this study has been clearly documented under section 5.