PHASE, a portable host access system environment

The portable host access system environment (PHASE) allows portable PCs to change their point of connection to the internet and continue to be accessible by a fully specified internet domain name. The author offers a solution to the problem of maintaining a proper mapping of internet protocol (IP) addresses to portable machines that have the ability to assume different IP addresses. The portable host access component (PHAC) of the PHASE provides a temporary IP address to each PC that connects to it. A modified internet domain name server, called the dynamic domain name server (DDNS), automatically manages the temporary IP addresses of PCs and provides a mechanism for other hosts to connect to the portable PC. The pros and cons of different methods used to ensure the integrity of the DDNS database are discussed. As a result of this technology, internet hosts can now initiate connections to portable hosts. This gives PCs connected to the PHAC the ability to run server protocols. An example military application of a mobile communications environment involving a portable PC connected to the PHAC, running an SMTP (simple mail transfer protocol) server protocol is portrayed