retrotom 

Keryx: a from-scratch WebRTC stack for .NET. This package is the composition root - an RTCPeerConnection-style API over the Keryx STUN/ICE/SDP/DTLS/SRTP/RTP/SCTP layers.

DTLS 1.2 handshake state machine and record layer (built on System.Security.Cryptography primitives) with SRTP keying-material export, from the Keryx WebRTC stack.

ICE agent (host, server-reflexive and TURN-relayed gathering, connectivity checks, nomination) from the Keryx WebRTC stack.

STUN (RFC 5389) message encoding, decoding and a lightweight client, from the Keryx WebRTC stack.

TURN client (RFC 8656): allocations, permissions, channel bindings and relayed datagrams, from the Keryx WebRTC stack.

Keryx core primitives: binary readers/writers, transport and logging abstractions shared by every Keryx layer.

SCTP over DTLS and WebRTC data channels (DCEP) from the Keryx WebRTC stack.

SRTP/SRTCP protection (AES-CM + HMAC-SHA1, RFC 3711) from the Keryx WebRTC stack.

RTP and RTCP packet model, typed RTCP feedback (PLI/FIR/NACK/transport-cc) and media packetizers (H.264, Opus) from the Keryx WebRTC stack.

SDP parsing and generation (JSEP offer/answer subset) from the Keryx WebRTC stack.

Pure-managed SIMD H.264 baseline-profile encoder for real-time streaming. No native dependencies; NEON, AVX2 and SSSE3 accelerated.