Cisco Systems Cisco Systems Flarion Technologies Birdstep Technology ASA An IP device requires basic host configuration to be able to communicate. For example, it will typically require an IP address and the address of a DNS server. This information is configured statically or obtained dynamically using Dynamic Host Configuration Protocol (DHCP) or Point-to-Point Protocol/IP Control Protocol (PPP/IPCP). However, both DHCP and PPP/IPCP provide host configuration based on the access network. In Mobile IPv4, the registration process boots up a Mobile Node at an access network, also known as a foreign network. The information to configure the host needs to be based on the home network. This document describes the Cisco vendor-specific extensions to Mobile IPv4 to provide the base host configuration in Registration Request and Reply messages. This memo provides information for the Internet community.