Apple Inc. Google Karlstad University University of Aberdeen University of Glasgow TU Berlin Apple Inc. This document describes an architecture for exposing transport protocol features to applications for network communication, the Transport Services architecture. The Transport Services Application Programming Interface (API) is based on an asynchronous, event-driven interaction pattern. It uses messages for representing data transfer to applications, and it assumes an implementation that can use multiple IP addresses, multiple protocols, and multiple paths, and provide multiple application streams. This document further defines common terminology and concepts to be used in definitions of Transport Services APIs and implementations.