Several architectures have been recently proposed to support IP mobility. Most studies, however, show that current protocols, in general, fall short from satisfying the performance requirements for audio applications. In this study, we propose a multicast-based protocol to reduce latency and packet loss during handoff and provide the base for IP mobility support. We use extensive simulation to evaluate our protocol's performance over a variety of real and generated topologies, and we compare it to several other mobility protocols, especially the Mobile IP protocols. We take handoff delay estimates and routing efficiency as metrics for our comparisons. We take a route analysis (as opposed to packet analysis) approach in our study, and we apply it in the context of wide-area networks. Our simulation results show significant improvement for our proposed protocol. On average, basic Mobile IP consumes almost twice as much network bandwidth, and experiences more than twice as much end-...