Rebex WebSocket

WebSocket library for modern and legacy platforms

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// create an instance of WebSocket client
var client = new WebSocketClient();

// connect to a server
client.Connect("ws://echo.example.org");

// send a text message
client.Send("Hello!");

// receive a text message
string response = client.Receive();

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Rebex WebSocket is a WebSocket client library for .NET. It brings TLS 1.3, TLS 1.2, 1.1, SHA-2, SNI, AES/GCM and other modern security-related features to legacy platforms. Additionally, it supports TLS 1.3 on all mainstream platforms including .NET Framework 3.5 on Windows 7. Rebex WebSocket is designed to offer an easy-to-use API in addition to the advanced .NET ClientWebSocket API.

Why Rebex WebSocket?

Multiplatform WebSocket client

WebSockets are becoming increasingly popular, but support in .NET is far from perfect. Versions of .NET prior to 4.5 don't support WebSockets at all, and even .NET 4.5 only supports WebSockets on Windows 8 or higher.

Rebex WebSocket supports legacy platforms (including .NET Framework 2.0/3.5 and .NET Compact Framework 3.5/3.9) and works on legacy operating systems (Windows Vista SP1, Windows XP SP3, Windows Mobile 5/6, Windows CE, Pocket PC, Windows Embedded Compact). Of course, modern platforms such as .NET 5-10 are supported as well.

TLS 1.3 or TLS 1.2 on Windows XP, Windows 7, or Windows CE

Rebex WebSocket implements the following modern TLS features:

TLS 1.3, 1.2, 1.1, or 1.0 on Windows 7 or higher
TLS 1.3, 1.2, 1.1, or 1.0 on Windows XP SP3 or higher
TLS 1.3, 1.2, 1.1, or 1.0 on legacy .NET Compact Framework 3.5/3.9
Elliptic Curve DSA (ECDSA) digital signature algorithm
RSA digital signature algorithm
Ed25519 digital signature algorithm
ML-DSA post-quantum digital signature algorithm
Elliptic Curve Diffie-Hellman (ECDH) key exchange
ML-KEM post-quantum key exchange
Modular Diffie-Hellman key exchange
AES/GCM ciphers
ChaCha20/Poly1305 ciphers
SHA-2 certificates and hashing algorithms
OCSP stapling
Server Name Indication (SNI) extension
Renegotiation Indication extension
And more...

Note: ECDSA, ECDH require a plugin on very old systems. ML-KEM requires a plugin unless running on Windows 11 25H2. ML-DSA requires a plugin unless running on Windows 11 25H2 or up-to-date Linux with .NET 10.