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WebSocket Standards Tracker

Stay up-to-date with the evolving WebSocket ecosystem. This page tracks all WebSocket-related specifications, their current status, browser implementations, and upcoming changes that may affect your applications.

Current Standards Status

Core Specifications

📄 RFC 6455: The WebSocket Protocol

Status: Internet Standard Last Updated: December 2011 Stability: Stable ✅

The foundational WebSocket protocol specification defining the framing, handshake, and core protocol mechanics.

Read RFC 6455

🌐 WHATWG WebSockets Living Standard

Status: Living Standard Last Updated: Continuously updated Stability: Stable with ongoing improvements ✅

The browser API specification defining how WebSockets work in web browsers.

View Living Standard

🗜️ RFC 7692: Compression Extensions

Status: Proposed Standard Last Updated: December 2015 Stability: Stable with security considerations ⚠️

Defines permessage-deflate compression extension for WebSocket.

Read RFC 7692

⚡ RFC 8441: HTTP/2 WebSockets

Status: Proposed Standard Last Updated: September 2018 Stability: Experimental implementation 🚧

Bootstrapping WebSockets over HTTP/2 using Extended CONNECT.

Read RFC 8441

🚀 RFC 9220: HTTP/3 WebSockets

Status: Proposed Standard Last Updated: June 2022 Stability: Early implementation 🚧

Bootstrapping WebSockets over HTTP/3 and QUIC.

Read RFC 9220

⏩ W3C WebTransport

Status: Working Draft Last Updated: October 2024 Stability: Experimental 🔬

Next-generation bidirectional communication protocol built on HTTP/3.

View WebTransport Draft

Browser Implementation Status

Core WebSocket API (RFC 6455)

FeatureChromeFirefoxSafariEdge
Basic WebSocket✅ 16+✅ 11+✅ 7+✅ 12+
Binary data✅ 16+✅ 11+✅ 7+✅ 12+
Sub-protocols✅ 16+✅ 11+✅ 7+✅ 12+
Extensions✅ 16+✅ 11+✅ 7+✅ 12+
Secure WebSocket (WSS)✅ 16+✅ 11+✅ 7+✅ 12+

Compression (RFC 7692)

FeatureChromeFirefoxSafariEdge
permessage-deflate✅ 32+✅ 37+✅ 9+✅ 12+
Client context takeover✅ 32+✅ 37+✅ 9+✅ 12+
Server context takeover✅ 32+✅ 37+✅ 9+✅ 12+
Window bits negotiation✅ 32+✅ 37+✅ 9+✅ 12+

HTTP/2 WebSockets (RFC 8441)

FeatureChromeFirefoxSafariEdge
Extended CONNECT✅ 91+❌❌✅ 91+
pseudo-header		✅ 91+❌❌✅ 91+
SETTINGS_ENABLE_CONNECT_PROTOCOL✅ 91+❌❌✅ 91+

HTTP/3 WebSockets (RFC 9220)

FeatureChromeFirefoxSafariEdge
HTTP/3 WebSocket bootstrap🚧 Experimental❌❌🚧 Experimental
QUIC transport✅ 87+ (HTTP/3)✅ 88+ (HTTP/3)✅ 14+ (HTTP/3)✅ 87+ (HTTP/3)
Extended CONNECT over HTTP/3🚧 Flag required❌❌🚧 Flag required

WebTransport

FeatureChromeFirefoxSafariEdge
WebTransport API✅ 97+🚧 114+ (Nightly)❌✅ 97+
Datagrams✅ 97+🚧❌✅ 97+
Streams✅ 97+🚧❌✅ 97+
Connection pooling✅ 97+🚧❌✅ 97+

Server Implementation Status

Web Servers

ServerHTTP/1.1 WebSocketHTTP/2 WebSocketHTTP/3 WebSocket
Nginx✅ 1.3.13+✅ 1.25+🚧 Experimental
Apache✅ 2.4+ (mod_proxy_wstunnel)❌❌
Caddy✅ v1+✅ v2+✅ v2.6+
HAProxy✅ 1.4+✅ 2.0+🚧 2.6+
Node.js✅ All versions✅ 10.0+🚧 Experimental
IIS✅ 8.0+✅ 10+❌

CDN/Proxy Support

ProviderWebSocket SupportHTTP/2HTTP/3Notes
Cloudflare✅✅✅100-second timeout
AWS CloudFront✅✅✅Regional edge locations
AWS ALB✅❌❌4000-second timeout
Google Cloud LB✅✅🚧Global load balancing
Azure App Gateway✅✅❌Session affinity required
Fastly✅✅✅Real-time purging

What’s New - December 2024

Recent Updates

Browser Updates

  • Chrome 120: Improved WebSocket performance over HTTP/3
  • Firefox 120: Fixed WebSocket memory leak in Worker contexts
  • Safari 17.1: Enhanced WebSocket debugging in Web Inspector
  • Edge 120: Aligned with Chromium WebSocket implementation

Specification Updates

  • WHATWG Living Standard: Clarified binaryType behavior for ArrayBuffer
  • WebTransport: Added connection migration capabilities
  • HTTP/3 Draft: Refined SETTINGS negotiation for WebSocket

Security Advisories

  • CVE-2024-XXXX: WebSocket compression vulnerability in certain configurations
  • Best Practice Update: New recommendations for origin validation

Upcoming Changes - Q1 2025

Planned Browser Features

  • Chrome 121: WebSocket priority hints API
  • Firefox 122: HTTP/2 WebSocket support (experimental)
  • Safari 18: WebTransport implementation (preview)

Draft Specifications

  • WebSocket over QUIC: Direct QUIC transport without HTTP/3
  • WebSocket Priorities: QoS and stream prioritization
  • WebSocket Multipath: Connection migration and fallback

Implementation Guides

Detecting Feature Support

// Check basic WebSocket support
if ('WebSocket' in window) {
  console.log('WebSocket supported');
}


// Check for specific features function checkWebSocketFeatures() { const
features = { basic: 'WebSocket' in window, binaryType: false, compression:
false, protocols: false };


if (features.basic) { try { const ws = new
WebSocket('wss://echo.websocket.org'); features.binaryType = 'binaryType' in ws;
features.protocols = ws.protocol !== undefined;


      // Check for compression support
      ws.onopen = () => {
        features.compression = ws.extensions.includes('permessage-deflate');
        ws.close();
      };
    } catch (e) {
      console.error('WebSocket test failed:', e);
    }


}


return features; }


// Check WebTransport support if ('WebTransport' in window) {
console.log('WebTransport supported'); }

Protocol Negotiation

// Negotiate best available protocol
async function connectWithBestProtocol(url) {
  const caps = await ProtocolDetector.detectCapabilities();


  // Try WebTransport first (if available and supported)
  if (caps.webtransport && url.startsWith('https://')) {
    try {
      const transport = new WebTransport(url);
      await transport.ready;
      console.log('Connected via WebTransport');
      return transport;
    } catch (e) {
      console.log('WebTransport failed, falling back');
    }
  }


  // Fall back to WebSocket
  if (caps.websocket.secure) {
    const ws = new WebSocket(url.replace('https://', 'wss://'));
    await new Promise((resolve, reject) => {
      ws.onopen = resolve;
      ws.onerror = reject;
    });
    console.log('Connected via WebSocket');
    return ws;
  }


  throw new Error('No suitable protocol available');
}

Migration Guides

HTTP/1.1 to HTTP/2 WebSockets

# Nginx configuration for HTTP/2 WebSocket
server {
    listen 443 ssl http2;
    server_name example.com;


    # Enable HTTP/2 WebSocket support (Nginx 1.25+)
    http2_recv_timeout 300s;
    http2_idle_timeout 300s;


    location /ws {
        proxy_pass http://backend;
        proxy_http_version 1.1;


        # Standard WebSocket headers
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";


        # HTTP/2 specific settings
        proxy_set_header X-Forwarded-Proto $scheme;
        proxy_buffering off;


        # Extended CONNECT support
        proxy_set_header :protocol websocket;
    }
}

WebSocket to WebTransport Migration

// Abstraction layer for protocol migration
class RealtimeConnection {
  constructor(url, options = {}) {
    this.url = url;
    this.options = options;
    this.protocol = null;
  }


  async connect() {
    // Try WebTransport
    if ('WebTransport' in window && this.url.startsWith('https://')) {
      try {
        return await this.connectWebTransport();
      } catch (e) {
        console.log('WebTransport unavailable, using WebSocket');
      }
    }


    // Fall back to WebSocket
    return await this.connectWebSocket();
  }


  async connectWebTransport() {
    this.transport = new WebTransport(this.url);
    await this.transport.ready;
    this.protocol = 'webtransport';


    // Set up bidirectional stream
    const stream = await this.transport.createBidirectionalStream();
    this.reader = stream.readable.getReader();
    this.writer = stream.writable.getWriter();


    return this;
  }


  async connectWebSocket() {
    const wsUrl = this.url
      .replace('https://', 'wss://')
      .replace('http://', 'ws://');


    this.ws = new WebSocket(wsUrl);
    this.protocol = 'websocket';


    return new Promise((resolve, reject) => {
      this.ws.onopen = () => resolve(this);
      this.ws.onerror = reject;
    });
  }


  async send(data) {
    if (this.protocol === 'webtransport') {
      const encoded = new TextEncoder().encode(data);
      await this.writer.write(encoded);
    } else {
      this.ws.send(data);
    }
  }


  async receive() {
    if (this.protocol === 'webtransport') {
      const { value } = await this.reader.read();
      return new TextDecoder().decode(value);
    } else {
      return new Promise((resolve) => {
        this.ws.onmessage = (event) => resolve(event.data);
      });
    }
  }


  close() {
    if (this.protocol === 'webtransport') {
      this.transport.close();
    } else {
      this.ws.close();
    }
  }
}

Standards Participation

Working Groups

Contributing to Standards

  1. Report Issues: File bugs in specification repositories
  2. Join Discussions: Participate in mailing lists and GitHub issues
  3. Submit Proposals: Write Internet-Drafts for new features
  4. Implement Early: Test experimental features and provide feedback
  5. Document Use Cases: Share real-world requirements and constraints

Email Subscription

Stay informed about WebSocket standards updates with our monthly digest.

What You’ll Receive

  • Standards Updates: New RFCs and specification changes
  • Browser Releases: Implementation updates and new features
  • Security Advisories: Important vulnerability disclosures
  • Migration Guides: Best practices for adopting new standards
  • Matthew O’Riordan’s Analysis: Expert commentary on implications

📧 Subscribe to Standards Watch

Get monthly updates on WebSocket standards and implementations delivered to your inbox.

Coming Soon - Email subscription system under development.

Follow @mattyoriordan for updates.

Compliance Testing

Autobahn TestSuite Compliance

Track your WebSocket implementation’s compliance with the protocol specification:

Terminal window
# Run Autobahn TestSuite
docker run -it --rm \
  -v "${PWD}/config:/config" \
  -v "${PWD}/reports:/reports" \
  crossbario/autobahn-testsuite \
  wstest -m fuzzingclient -s /config/fuzzingclient.json

Current Compliance Levels

ImplementationRFC 6455RFC 7692Pass Rate
Chrome 120✅ 100%✅ 100%517/517
Firefox 120✅ 100%✅ 100%517/517
Safari 17✅ 100%✅ 100%517/517
Node.js ws✅ 100%✅ 100%517/517
Python websockets✅ 100%✅ 100%517/517
Go gorilla✅ 99.8%✅ 100%516/517

Resources

Official Specifications

Implementation Status