The purpose of the Dynamic Host Configuration Protocol (DHCP) service is that when a computer is attached to a particular network, it may enquire particular details of its environment, and be supplied with a temporary Internet Protocol (IP) address from a special pool. This meets two needs: as portable computers roam between different networks their IP addresses need to change accordingly, preferably without the need for user intervention; as the number of hosts connected to the Internet continues to grow, there is developing a shortage of available IP addresses. A web interface is provided for departmental and college Information Technology Officers to register the Media Access Control addresses of computers within their unit that wish to allow to use the service.