Knowledge of the Internet Protocol (IP) address is essential for connection establishment in certain classes of synchronous distributed applications, such as Internet telephony and video-conferencing systems. A problem of dynamic IP addressing arises when the connection to the Internet is through an Internet service provider, since the IP address is dynamically allocated only at connection time. Proposes and draws a contrast between a number of generic methods that can be classified as online and offline methods for the resolution of dynamic IP addressing. Online methods, which include the World Wide Web, exchange server and the dynamic Domain Name System, are only effective when both the caller and recipient are logged on to the Internet. On the other hand, offline methods, which include electronic mailing and directory service look-up, provide an additional means to allow the caller to leave messages when the recipient is not logged on to the Internet. Of these methods, the dynamic Domain Name System and directory service look-up appear to be the best for resolving dynamic IP addressing.