Abstract: An application programming interface (API) between user applications or other control applications and User to Network Interface (UNI) signaling software. The API provides an intelligent and flexible programming interface which enables higher layer software such as user application software to set up and tear down ATM connections more efficiently. The API provides an efficient method of activating the standard signaling procedures such as UNI signaling as compared to the prior art method. Shared sets of parameters defining the setting up and the tearing down of calls are predefined by the user or provided as defaults by the API itself. Instead of requiring a user application to specify every single call related parameter, only the set of predefined parameters needs to be identified which significantly increases the throughput of the underlying signaling stack. Since the predefined sets of parameters are already encoded, the time required to process the call parameters is greatly reduced.