Network & Outside Network Broadcasting

CASTIUM provides built-in capabilities to broadcast your station over your local home network (Wi-Fi / LAN) and across the internet to remote listeners outside your local network.

How It Works

1. Dual-Mode HTTP Stream Server & Zero-Config Socket Bridge:

   • CASTIUM binds its embedded HTTP streaming server (HttpStreamServer) to serve on all network interfaces.
   • On Windows, kernel-level HTTP.sys URL reservations normally require administrative privileges to bind non-localhost IPs. CASTIUM incorporates an automatic, zero-permission TCP socket bridge (TcpListener) fallback on the configured port.
   • This ensures that standard non-elevated user runs work seamlessly out of the box on all local IPv4/IPv6 addresses (192.168.x.x, 10.x.x.x), custom domains, and Wi-Fi networks without requiring UAC prompts or returning HTTP 400 Bad Request - Invalid Hostname.
   • Listeners on the same Wi-Fi or LAN can connect immediately without special configuration by pointing their browser or media player to http://<Local-IP>:<Port>.

2. Outside of Local Network (Internet) Access:

   • Remote listeners outside of your local network can reach your stream using your public IP address: http://<Public-IP>:<Port>.
   • To route incoming traffic through your home router without manual router administration, CASTIUM includes native Windows UPnP NAT port mapping (HNetCfg.NATUPnP).
   • When UPnP Router Port Forwarding is enabled in CASTIUM, CASTIUM asks your router to automatically forward your station port to your local machine.

3. Custom Public Domain / Host / IP Override & Reverse Proxy Settings:

   • If you use Dynamic DNS (e.g. DuckDNS, No-IP) or run CASTIUM behind a reverse proxy (e.g. Caddy, Nginx, Apache, or Cloudflare Tunnel) with SSL/TLS, you can configure your host and connection options in the Network & Internet Broadcasting card:

     Custom Domain / Public Host (Optional)
     [ radio.mydomain.com ]
     [x] Use HTTPS (https://)     [x] Using Reverse Proxy (Remove Port)
     

   • Use HTTPS: Automatically switches generated outside URLs and playlists from http:// to https://.
   • Using Reverse Proxy: Automatically removes the local server port (e.g. :9696) from generated outside URLs and playlists, making it seamless to copy/paste and open addresses managed by reverse proxies on standard HTTP/HTTPS ports (80/443).
   • When configured, CASTIUM automatically formats and propagates these preferences across:
     • The Outside Network URL box and "Open ↗" button.
     • The Share Broadcast modal.
     • The VLC & Media Players Endpoint (/<mount>).
     • Live .m3u and .pls playlist generators.
   • Click ✕ Reset to revert immediately to your auto-detected public WAN IP.

4. Configurable Live Stream URL Mount Path:

   • The broadcaster can customize the audio streaming endpoint path (e.g. /live, /radio, /metal, or /station) directly in the Network & Internet Broadcasting console card.
   • Quick preset buttons (stream, live, radio, station) allow instant one-click switching.
   • For complete backwards compatibility with existing bookmarks, media player links, and PWAs, the default /stream path remains active as an automatic alias alongside the custom mount point.
   • Playlists (.m3u and .pls) automatically update to point to the configured mount point (e.g., /radio.m3u).

5. Restrict to Local Network Only (Private Stream Mode):

   • When Restrict to Local Network Only is enabled in the Network card:
     • Listeners on the local Wi-Fi or LAN (192.168.x.x, 10.x.x.x, 172.16.x.x, localhost) continue to have full broadcasting and playback capabilities.
     • External/remote visitors connecting over the public internet see a full-page "🔒 Private Stream" banner masking the player with no access to audio, track metadata, queue, or live chat.
     • Direct audio requests from non-local IPs return 403 Forbidden with a JSON explanation.

6. Direct Media Player Endpoints & Playlists:

   • In addition to the interactive web player at the root URL (/), CASTIUM exposes direct audio endpoints at /<mount> and /stream.
   • This endpoint delivers chunked HTTP audio streams natively compatible with desktop and mobile media players:
     • VLC Media Player: Media → Open Network Stream (Ctrl+N) → paste http://<Host>:<Port>/<mount>.
     • Winamp / foobar2000 / mpv: File → Open URL.
     • M3U / PLS Playlists: Direct download via http://<Host>:<Port>/<mount>.m3u or /listen.m3u.

7. Console Management & Share Controls:

   • Network & Internet Broadcasting Card: Allows broadcasters to toggle network access, toggle UPnP router forwarding, monitor UPnP forwarding status, configure live stream mount paths, toggle private LAN-only mode, enter custom domain overrides, and copy connection URLs with one click.
   • Top Bar Quick Share: When ON AIR, a "Share Stream" button in the top navigation bar opens a quick modal with direct links for local LAN and remote internet listeners.
   • Persistence: Network broadcasting, custom mount points, private LAN restriction, custom URLs, and UPnP preferences are persisted automatically to ~/.CASTIUM/<Profile>.json.