Acts as both client and server program. IPUP sits quite happily on your system tray and can even email you when an IP notification is received, ideal if you are away from the office and need to easily get your clients IP address.By purchasing a single license you are entitled to run one server and one client. With an unlimited license you are free to distribute it within your company and to your clients. IPUP is provided as a 30 day trial with no nagscreens and no restrictions.