An incomplete list with RTC related standards and network protocols
SIP related
RFC 3261: SIP: Session Initiation Protocol
RFC 3262: Reliability of Provisional Responses in (SIP)
RFC 3263: Locating SIP Servers
RFC 3264: An Offer/Answer Model with the Session Description Protocol (SDP)
RFC 3265: Session Initiation Protocol (SIP)-Specific Event Notification
RFC 4566: SDP: Session Description Protocol
RFC 3581: An Extension to the Session Initiation Protocol (SIP) for Symmetric Response Routing
RFC 3605: Real Time Control Protocol (RTCP) attribute in Session Description Protocol (SDP)
RFC 3711: The Secure Real-time Transport Protocol (SRTP)
RFC 5763: Framework for Establishing a Secure Real-time Transport Protocol (SRTP)
RFC 4028: Session Timers in the Session Initiation Protocol (SIP)
RFC 4568: Session Description Protocol (SDP) Security Descriptions for Media Streams
RFC 5761: Multiplexing RTP Data and Control Packets on a Single Port
RFC 6189: ZRTP: Media Path Key Agreement for Unicast Secure RTP
WebRTC related
RFC 7118: The WebSocket Protocol as a Transport for the Session Initiation Protocol (SIP)
RFC 7478: Web Real-Time Communication Use Cases and Requirements
RFC 7874: WebRTC Audio Codec and Processing Requirements
RFC 7742: WebRTC Video Processing and Codec Requirements
ICE, STUN, TURN
RFC 8445: Interactive Connectivity Establishment (ICE): (NAT) Traversal
RFC 5389: Session Traversal Utilities for NAT (STUN)
RFC 7350: DTLS as Transport for Session Traversal Utilities for NAT (STUN)
RFC 5766: TURN Relay Extensions to Session Traversal Utilities for NAT (STUN)
TLS, DTLS
RFC 5246: TLS v1.2
RFC 8446: TLS v1.3
RFC 6347: DTLS
TCP/IP, UDP/IP
RFC 1180: A TCP/IP Tutorial
RFC 793: TCP - Old but Gold
RFC 768: UDP