Apple Inc. Apple Inc. This document provides a survey of commonly used or notable network security protocols, with a focus on how they interact and integrate with applications and transport protocols. Its goal is to supplement efforts to define and catalog transport services [RFC8095] by describing the interfaces required to add security protocols. It examines Transport Layer Security (TLS), Datagram Transport Layer Security (DTLS), Quick UDP Internet Connections with TLS (QUIC + TLS), MinimalT, CurveCP, tcpcrypt, and Internet Key Exchange with Encapsulating Security Protocol (IKEv2 + ESP). This survey is not limited to protocols developed within the scope or context of the IETF.