We use simulation to evaluate ROAM and Mobile IP with triangle routing,
bidirectional routing. We show
that routing efficiency and fault tolerance are proportional to the
amount of mobility infrastructure (either 
servers in or Home
Agents in Mobile IP) deployed. However, for moderate amounts of
infrastructure, ROAM provides higher routing efficiency and fault
tolerance than Mobile IP. In addition, ROAM's routing efficiency and
fault tolerance scale with the amount of infrastructure devoted to it.