Abstract: Despite the popularity of mobile computing platforms, appropriate system support for mobile operation is lacking in the Internet. This paper argues this is not for lack of deployment incentives, but because a comprehensive system architecture that efficiently addresses the needs of mobile applications does not exist. We identify five fundamental issues raised by mobility-location, preservation of communication, disconnection handling, hibernation, and reconnection-and suggest design guidelines for a system that attempts to support Internet mobility. In particular, we argue that a good system architecture should (i) eliminate the dependence of higher protocol layers upon lower-layer identifiers; (ii) work with any application-selected naming scheme; (iii) handle (unexpected) network disconnections in a graceful way, exposing its occurrence to applications; and (iv) provide mobility services at the mobile nodes themselves, rather than via proxies. Motivated by these principles, we propose a session-oriented, end-to-end architecture called Migrate, and briefly examine the set of services it should provide.