XLTD VPN

Stable Android and Windows VPN clients for olcRTC universal-carrier profiles and the XLTD-maintained mtsRTC MTS Link fork.

Current stable line:

Platform	Version	Notes
Android	1.10.0-universal-carrier	v3 graphite+blue+lime design, live download speed hero, single seichannel (multipath removed).
Windows	0.6.0-beta	v3 palette, 4-metric home grid, transport chips, rail footer, boot crash fix, multipath removed from YAML.

The isolated Xray work lives on branch alpha/xray-0.0.1 and is versioned as 0.0.x-alpha. The stable main branch stays focused on olcRTC and MTS Link.

Repository Layout

Path	Purpose
app/	Android application.
olcrtcbridge/	Android bridge module for the native olcRTC runtime.
windows/XLTD.Vpn.Windows/	Native Windows client.
scripts/	Android, Windows, olcRTC, packaging, and release helpers.
.external/olcrtc/	Local checkout/cache of l1ch666/mtsRTC, used for bundled olcRTC cores.

Generated outputs stay out of git: .tmp/, .external/ binaries, .gradle/, build/, app/build/, dist/, and generated app/libs/*.aar.

Supported olcRTC Profiles

olcrtc://<carrier>?<transport><params>@<roomId>#<64_hex_key>$<comment>

Accepted transports:

datachannel
vp8channel
seichannel
videochannel

Practical defaults:

• jitsi + datachannel is the fastest ordinary olcRTC path.
• telemost + vp8channel is the main stable Telemost path.
• mtslink + seichannel is the recommended MTS Link VPN path (single channel; multipath was removed as unstable).
• videochannel remains available for diagnostics and legacy visual transport profiles when an ffmpeg-backed core is bundled.

Old links with %clientId still parse. Copied server output that contains a uri: olcrtc://... line is accepted too.

MTS Link

The bundled MTS Link core comes from:

l1ch666/mtsRTC
branch: mtslink-universal-carrier

MTS Link joins a public room as a guest and negotiates the H.264/Opus media shape expected by the service. Normal VPN traffic should use seichannel, which carries data in H.264 SEI payloads. Single-channel mode is the only supported and tested configuration. videochannel is kept for diagnostics and legacy visible-video tests.

Android 1.10.0 brings the v3 graphite-dark + electric-blue + lime design: download-speed hero (live rate replaces session-bytes counter), lime signal bars, blue connect gradient, v3 palette throughout. Multipath (mc-lanes etc.) is removed; SEI runs single-channel.

Windows 0.6.0-beta mirrors the Android v3 palette, adds 4-metric cards and transport chips to the home page, adds a live rail footer (SOCKS / Route mode / Core state), and fixes the blank-UI bug when the boot API calls throw.

What changed since 1.9.5 / 0.5.5

• v3 design palette. Graphite-dark #0E1014, electric-blue #2D7DFF, lime #C9FF3D. Hero download-speed arrow is lime. Connect button is blue gradient. Signal bars glow lime when active.
• Single seichannel. mc-lanes, mc-control-lanes, mc-connect-parallel, mc-min-ready, mc-max-streams-per-lane and the traffic-shaping params are removed from all UI, defaultTransportSpec, saveSettings, and the Windows YAML builder. Multipath proved unreliable; single channel is stable.
• Home speed hero. The big 46 sp number now shows live download rate (Android) / is labelled with the speed value (Windows), not session bytes.
• Boot crash fix (Windows). boot() is now wrapped in try/catch so a failing api.* call no longer leaves the renderer blank.
• Rail footer (Windows). Shows SOCKS address, current route mode, and core running state at all times.

See MTSLINK.md for the server YAML, URI examples, and diagnostics.

Build

Android

From Git Bash or a Linux shell:

bash scripts/build_combo_aar.sh

Then build the debug APK:

powershell -ExecutionPolicy Bypass -File scripts/build_apk.ps1

The APK is copied to dist/ and the helper prints a SHA256 hash for release notes.

Windows

powershell -ExecutionPolicy Bypass -File scripts/build_windows.ps1

Output:

dist/windows/XLTD_Vpn-Windows-0.6.0-beta-win-x64.zip

The Windows package includes:

• XLTD_Vpn_Windows.exe
• tools/olcrtc.exe
• tools/ffmpeg.exe
• tools/tun2socks.exe
• tools/wintun.dll
• tools/data/names
• tools/data/surnames

Documentation

• MTSLINK.md - MTS Link setup and diagnostics.
• WINDOWS.md - Windows beta behavior and packaging.
• CHANGELOG.md - release history.
• MAINTENANCE.md - checks, versioning, publishing, and cleanup rules.

Naming Standard

• Product name: XLTD VPN.
• Android artifact prefix: XLTD_Vpn.
• Windows executable/package prefix: XLTD_Vpn_Windows / XLTD_Vpn-Windows.
• olcRTC fork repository: mtsRTC.
• MTS carrier name in links and configs: mtslink.
• Stable Android releases: v1.10.x.
• Windows beta releases: windows-v0.6.x-beta.