LabTetherProtocol Support Matrix
Desktop and terminal protocol compatibility across platforms. This reference covers which protocols work where and what each requires.
Desktop protocols
| Protocol | Latency | Clipboard | File Transfer | Recording | Multi-Monitor | Audio |
|---|---|---|---|---|---|---|
| WebRTC | Excellent (peer-to-peer) | Yes (direct) | Yes (data channel) | Yes (browser-local WebM) | Yes (stitched layout) | Yes |
| VNC | Good | Yes (agent-backed) | Yes (download, agent-backed) | Backend-dependent | Yes (display picker) | Yes (agent-backed) |
| RDP (via guacd) | Good | Limited (guacd-dependent) | No | No | Upstream-dependent | Upstream-dependent |
| SPICE | Good | No | No | No | Upstream-dependent | No |
Platform compatibility
| Protocol | Linux | macOS | Windows | Proxmox VMs | FreeBSD |
|---|---|---|---|---|---|
| WebRTC | Yes (agent required) | Planned | Planned | Via agent inside VM | Planned |
| VNC | Yes | Yes (Screen Sharing) | Yes (VNC server required) | Yes (default for Proxmox) | Yes (VNC server required) |
| RDP | No | No | Yes (native) | No | No |
| SPICE | No | No | No | Yes (SPICE display adapter required) | No |
Selection priority
LabTether selects the best available protocol automatically, but you can override the choice in the desktop protocol picker.
| Priority | Protocol | When to use |
|---|---|---|
| 1 | WebRTC | Default choice when agent supports it -- best latency and richest feature set |
| 2 | VNC | Fallback when WebRTC is unavailable -- broadest compatibility |
| 3 | RDP | Windows-targeted workflows where native RDP behavior is preferred |
| 4 | SPICE | Proxmox VMs with a SPICE-capable display adapter |
Auto-fallback: If WebRTC connection quality degrades (quality badge stays at poor), LabTether automatically reconnects using VNC. If conditions improve, it can recover back to WebRTC.
Terminal protocols
| Protocol | Use Case | Default Port |
|---|---|---|
| SSH | Primary terminal access for all platforms | 22 |
| Telnet | Legacy devices, network switches | 23 |
SSH is the default and recommended terminal protocol. Telnet is supported for legacy devices that do not support SSH (network switches, older appliances). Telnet traffic is unencrypted between the hub and the target -- only use it on trusted networks.
Protocol dependencies
| Protocol | Required on target | Required on hub |
|---|---|---|
| WebRTC | Agent with WebRTC capability, GStreamer runtime | Signaling path (hub relays) |
| VNC | VNC server (x11vnc + Xvfb on Linux, Screen Sharing on macOS) |
WebSocket proxy |
| RDP | RDP enabled with valid credentials | guacd sidecar service |
| SPICE | Proxmox VM with SPICE display adapter | Proxmox connector, WebSocket proxy |
| SSH | SSH server | Agent connection or direct SSH access |
| Telnet | Telnet server | Direct network access |
For detailed protocol setup and troubleshooting, see Remote Desktop and Desktop Issues.