From the developer: DirectUpdate is a dynamic DNS client updater. It runs in the background on your machine and checks your public IP address periodically. When a new IP is detected, it udpates your dynamic dns accounts. It runs as an NT service, support remote administration, works behind a router/firewall, can send emails notification, can manage RAS (dial-up) connection... Dynamic DNS allows use of a permanent domain name with a dynamic Ip address changing every time you connect to your ISP.