Nokia Nokia This document specifies Mobile IP Regional Paging (MIRP), a small and link-layer independent extension to Mobile IP [2] with regional registrations [3], to support power-constrained operation in the mobile nodes and to reduce routing state information in the visited domain. The extension allows a mobile node to enter a power saving idle mode during which its location is known with the coarse accuracy defined by a paging area. Downlink routes to idle mobile nodes terminate in a paging foreign agent, which re-establishes them on demand by means of paging. This does not require snooping of data packets but is a natural extension to network-level routing. Optionally, the mobile node and the visited domain can agree on communication time slots used for Agent Advertisements and paging, to restrict link interface power-on time in the mobile node.