GameNetworkingSockets is Valve's production-grade C++ networking library for real-time multiplayer games. In actual operation it provides connection-oriented and message-oriented transport over UDP, with reliable and unreliable message delivery, fragmentation, retransmission, AES-GCM-256 encryption, Curve25519/Ed25519 key exchange, certificate-based authentication, and a full connection state machine. The library also implements peer-to-peer connectivity through ICE/STUN/TURN, WebRTC transport integration, and Steam Datagram Relay (SDR) in Steam builds, plus custom signaling support for non-Steam rendezvous. It is not a standalone application; it is an embeddable SDK whose primary public surface is the Steamworks-compatible C++ interfaces in include/steam (ISteamNetworkingSockets, ISteamNetworkingMessages, ISteamNetworkingUtils) and a flat C ABI wrapper. The main implementation lives in src/steamnetworkingsockets/clientlib, where the SNP reliable protocol, socket thread, direct UDP transport, P2P routing, and connection state machines are implemented, supported by a substantial private utility layer (tier0/tier1 containers, serialization buffers, string utilities) and multiple interchangeable crypto backends.
This repository is a static website hosted on GitHub Pages that curates resources for multiplayer game networking. It provides a comprehensive list of articles, videos, libraries, and tools related to game netcode, including topics like latency compensation, deterministic simulation, and various networking libraries. The site is built using Jekyll, with the content primarily in the README.md file. The repository also includes a trivial C program that prints a description of the project. While the repository is classified as an application (a static web site), it also functions as a curated data resource. The content is regularly updated, as evidenced by the inclusion of upcoming events (e.g., Bali 2025, Orlando 2025) in the README.md, indicating active maintenance. However, the codebase itself lacks reusable components, consisting mainly of configuration files and trivial code.