Trezor Bridge — Secure Connection for Your Trezor

1. What Is Trezor Bridge?

Trezor Bridge is a lightweight background service (daemon) that runs locally on your computer. It enables your browser or application (for example, Trezor Suite or other Web3-compatible tools) to communicate with your Trezor hardware wallet over USB in a secure, controlled manner. :contentReference[oaicite:0]{index=0}

Because modern browsers restrict direct USB access for security, Bridge acts as the mediator or translator, forwarding commands and responses between the host software and your device—without exposing your secrets. :contentReference[oaicite:1]{index=1}

2. Why Bridge Is Necessary

• USB & browser restrictions: Browsers often block or sandbox USB device access; Bridge helps navigate those constraints. :contentReference[oaicite:3]{index=3}
• Cross‑platform consistency: It handles OS-specific quirks, drivers, and permissions to provide a smoother user experience. :contentReference[oaicite:4]{index=4}
• Security layering: Bridge forwards commands but private keys never leave the Trezor. All sensitive actions (e.g. transaction signing) require confirmation on the hardware itself. :contentReference[oaicite:5]{index=5}
• Advanced features: Firmware updates, passphrase handling, and certain integrations are more reliably supported via Bridge. :contentReference[oaicite:6]{index=6}

3. Supported Platforms & Requirements

Trezor Bridge supports the major desktop operating systems and works with popular browsers. :contentReference[oaicite:7]{index=7}

• Windows (10, 11, and newer) :contentReference[oaicite:8]{index=8}
• macOS (modern releases) :contentReference[oaicite:9]{index=9}
• Linux distributions (Ubuntu, Debian, Fedora, etc.) :contentReference[oaicite:10]{index=10}

Hardware / connectivity requirements: A direct USB connection (avoid unverified hubs/extenders), and a browser or app that supports Trezor interfaces (e.g. Chrome, Firefox, Edge). :contentReference[oaicite:11]{index=11}

4. Installation & Setup Guide

Follow these steps to install and configure Trezor Bridge:

1. Download official Bridge: Go to the official Trezor site (e.g. via trezor.io/start) to fetch the correct Bridge installer. Avoid third-party or unverified sources. :contentReference[oaicite:12]{index=12}
2. Install for your OS:
   • Windows: Run the `.exe` or `.msi` installer, allow permissions. :contentReference[oaicite:13]{index=13}
   • macOS: Open `.dmg`, drag to Applications, approve any security prompts. :contentReference[oaicite:14]{index=14}
   • Linux: Use `.deb`, `.rpm`, or package manager. e.g. `sudo dpkg -i trezor-bridge‑x.x.x.deb`. :contentReference[oaicite:15]{index=15}
3. Launch/enable Bridge: After install, Bridge often runs silently in the background. Check system tray (Windows) or menu bar (macOS) to confirm it’s active. :contentReference[oaicite:16]{index=16}
4. Allow firewall / OS permissions: If your OS or security software blocks localhost or USB access, grant Bridge necessary permissions. :contentReference[oaicite:17]{index=17}
5. Connect Trezor: Plug your hardware wallet via USB. Then launch Trezor Suite or navigate to a supported web interface. The software should detect Bridge and prompt further setup. :contentReference[oaicite:18]{index=18}
6. Confirm device detection: The UI should show “Bridge detected” or “Device connected via Bridge.” At this point, you can proceed with transactions, firmware upgrades, etc. :contentReference[oaicite:19]{index=19}

5. How Bridge Communication Works (Architecture)

Here’s a simplified view of the communication flow:

1. Your browser or application (e.g. Trezor Suite Web) makes a request (e.g. “get addresses” or “sign transaction”).
2. The request is sent locally to Bridge (running on `localhost`). :contentReference[oaicite:20]{index=20}
3. Bridge receives it and forwards it (via encrypted channels) to the Trezor device connected over USB. :contentReference[oaicite:21]{index=21}
4. The Trezor device displays the request (amount, destination, options) and prompts you to confirm or reject. :contentReference[oaicite:22]{index=22}
5. If you confirm, the device signs or executes the operation (e.g. transaction), then returns a response. :contentReference[oaicite:23]{index=23}
6. Bridge relays that response back to the browser/application, which continues execution (e.g. broadcasts transaction). :contentReference[oaicite:24]{index=24}

Note: Bridge does **not** have access to private keys, seed, or PIN. It merely forwards commands. All security-sensitive decisions are enforced by the hardware wallet itself. :contentReference[oaicite:25]{index=25}

6. Security & Best Practices

While Bridge is designed with security in mind, your environment and behavior also matter. Observe these best practices:

• Always download Bridge from the official Trezor site (e.g. trezor.io/start) to avoid malicious copies. :contentReference[oaicite:26]{index=26}
• Verify the installer’s checksum or signature if provided. :contentReference[oaicite:27]{index=27}
• Keep Bridge, Trezor Suite, and your device firmware up to date. :contentReference[oaicite:28]{index=28}
• Avoid running multiple conflicting Bridge or similar software simultaneously. :contentReference[oaicite:29]{index=29}
• Whitelist localhost / USB permissions, but do not expose Bridge to external networks. :contentReference[oaicite:30]{index=30}
• Always verify transaction details (amount, address) on the device display before approving. :contentReference[oaicite:31]{index=31}
• Be cautious with browser extensions or third-party apps that might interfere or attempt to bypass Bridge. :contentReference[oaicite:32]{index=32}

7. Troubleshooting Common Issues

“Bridge not detected” or “Bridge is not running” errors

Make sure the Bridge service is active (check system tray / status). Restart your computer or reinstall Bridge. :contentReference[oaicite:33]{index=33}

Browser cannot connect even though Bridge is running

Restart the browser, clear cache, or try a different browser. Verify that the browser is allowed to connect to localhost. :contentReference[oaicite:34]{index=34}

USB / device not recognized

Use a different, high-quality USB cable. Avoid hubs or extensions. Try different USB ports. On Linux, check udev rules. :contentReference[oaicite:35]{index=35}

Permission / security restrictions (macOS, firewall, antivirus)

Grant Bridge the necessary permissions in OS settings or security prompts. Ensure your firewall allows localhost communication. :contentReference[oaicite:36]{index=36}

Update / installation failures

Download fresh installer, uninstall previous versions, and reinstall. Don’t resume partial installs. :contentReference[oaicite:37]{index=37}

Version mismatch between Bridge and client

Ensure your Trezor Suite or host app supports the installed Bridge version. Update or revert as needed. :contentReference[oaicite:38]{index=38}

8. Advanced & Developer Usage

If you are a power user or developer, you can interact with Bridge more directly:

• API / SDK usage: Bridge exposes a local API (e.g. JSON‑RPC) for host applications to talk to the device. Ensure you respect origin checks and security rules. :contentReference[oaicite:40]{index=40}
• Custom host apps: You may build apps that interface with Bridge, but they must be properly registered / trusted so Bridge does not reject them. :contentReference[oaicite:41]{index=41}
• Debug & logs: Bridge can produce logs for troubleshooting. Use verbose logging sparingly and avoid leaking sensitive data. :contentReference[oaicite:42]{index=42}
• Open source & audits: Key components of Bridge are open for review. You may review code, audit security, or contribute patches. :contentReference[oaicite:43]{index=43}

9. Example Walkthrough: Connecting & Transaction

Here’s a sample flow from “first connect” to sending funds, with Bridge in play:

1. Install Bridge and launch it.
2. Open your browser and navigate to Trezor Suite (web) or a supported Web3 interface.
3. Plug your Trezor device via USB.
4. The browser app contacts Bridge (via localhost). Bridge recognizes the device and forwards communication. :contentReference[oaicite:44]{index=44}
5. The app requests, say, “show receive address.” That request gets forwarded to your Trezor.
6. Your Trezor displays the address; you confirm it. The signed address is returned. :contentReference[oaicite:45]{index=45}
7. Later, when sending funds, the app requests “sign transaction.” Bridge forwards to device, which displays transaction details. You confirm on hardware. Signed transaction returns and is broadcast. :contentReference[oaicite:46]{index=46}