1.1 Introduction

This document defines the Telephony Service Provider Interface (TSPI) for Telephony under Microsoft® WindowsTM, version 3.1. The Windows TSPI defines the external interface of a Service Provider to be implemented by vendors of Telephony equipment. A Telephony Service Provider provides access to vendor-specific equipment through a standard Device Driver interface. Installing a Service Provider allows Windows 3.1 applications that use elements of telephony to access the corresponding telephony equipment.