The SCI provides a Smalltalk application with a set of classes and methods to construct tasks that use TCP/IP as a communication protocol. The functionality is a subset of the functionality found on a typical Unix network programming environment. The implementation model for the SCI is based on the Berkeley socket API specification as defined in Unix installation header files. The SCI is generic to the extent that any application that follows the SCI specification can be ported with minimal effort to any platform that runs SCI. Programmers wishing to use this interface should familiarize themselves with the Unix network programming environment.