Transparent Mobility with Minimal Infrastructure

seeks to address the problems that arise when individ-ual users have dozens of machines sharing their data and services. This paper addresses one key problem in such environment: each machine’s IP addresses may of-ten change due to mobility, due to switching between different network connections (e.g., Ethernet, 802.11, and infrared), and due to dynamic IP assignment (e.g., DHCP). Because higher level protocols and applications often implicitly assume that IP addresses correspond to specific, unchanging hosts, changes in the physical IP address used to reach a host can cause failures in these protocols and applications. To address this problem, we introduce VIP, a virtual IP layer, that applies the principle of virtual addressing to Internet naming. VIP presents an abstraction in whic