H1 — Introduction

Trezor Bridge historically served as the secure background service that allowed Trezor hardware wallets to communicate with desktop browsers and applications. It acted as a trusted bridge (a small local server/daemon) between the hardware device and higher-level wallet software such as Trezor Suite or web apps that wanted to talk to the device. This presentation lays out the technical role, security model, deployment steps, migration notes, and practical best practices for users, developers, and system administrators.

H2 — Why a Bridge layer?

Many modern browsers implement security constraints that make direct USB or HID access for websites non-trivial. A local bridge (a lightweight daemon) provides a consistent API surface, handles authentication, and offers a small, auditable codebase that mediates requests going to the hardware device. Put simply: the bridge minimizes attack surface on web-facing code and isolates device I/O behind a trusted local component.

H3 — Security model & trust assumptions

Trezor Bridge is designed under these core assumptions:

• Local trust boundary: only processes on the same host are allowed to connect to the bridge endpoint.
• Explicit user confirmations always required on the hardware device for sensitive actions (signing transactions, revealing keys).
• Open-source and auditable: the bridge codebase is available for review, enabling the security community to inspect and verify behavior.

H4 — High-level architecture

At runtime, Trezor Bridge runs as a small HTTP server bound to a localhost port (or similar IPC). Wallet software opens a local connection and sends well-defined API calls (enumerate devices, open device, send APDU/commands). The hardware device requires a physical confirmation for critical operations, which prevents silent remote extraction of secrets.

H5 — Lifecycle & updates

Bridge releases are provided as signed installers. Users should always install Bridge or Suite from official sources and verify signatures where available. Over time, Trezor Suite has integrated many Bridge capabilities directly; refer to the official guidance on deprecation and migration.

H1 — Installation & setup (practical)

H2 — Where to get Bridge

Only download Trezor Bridge (or Trezor Suite) from official sources listed below. Do not trust third‑party mirrors or random search results — many phishing sites try to imitate official pages. The list of verified, authoritative resources is embedded inside this presentation for quick access.

H3 — Quick install

1. Go to the official Trezor download page or the data.trezor.io mirror for the bridge package.
2. Download the installer appropriate for your OS (Windows, macOS, Linux).
3. Verify the digital signature if provided (PGP/sha256 checksums).
4. Run the installer and follow the on-screen instructions. The bridge runs as a background process called trezord or trezord-go.

Troubleshooting

Common issues and solutions:

• If the host app cannot find the Trezor device, ensure Bridge is running and that your OS drivers permit USB/HID access.
• On some platforms, prior Bridge installations may conflict with integrated Suite versions — follow the deprecation instructions to remove old standalone Bridge installations.
• Use the official guide pages (links below) to validate versions and signature files.

H1 — For developers

H2 — Integration patterns

Developers typically communicate to the device via one of two routes: Trezor Connect (a higher-level JS library) or direct calls to the Bridge API (a lower-level HTTP/hid interface). For web integrations, prefer the official Trezor Connect library which handles API versioning, user prompts, and error handling.

H3 — Security best practices for integrators

• Never request private keys from the device — use signing-only flows and keep raw keys on hardware.
• Validate library versions and pin dependencies to avoid supply-chain issues.
• Inform users about where to download official Bridge/Suite so they can verify authenticity.

H4 — Open-source resources

The primary repositories and release pages are maintained under the Trezor GitHub organization; developers can inspect the trezord-go sources or Suite release artifacts for deeper understanding.

H1 — Deprecation & modern alternatives

H2 — Moving away from standalone Bridge

Over time, browser APIs (e.g., WebUSB) and tighter integration inside Trezor Suite have reduced the need for a standalone Bridge. Trezor has published guidance for deprecation and recommended migration paths; users should follow those instructions carefully — especially when upgrading major OS or Suite versions.

H3 — When Bridge is still needed

Edge cases may require a standalone bridge: older browsers, specific third‑party wallet integrations, or systems where WebUSB is blocked. Carefully follow the official troubleshooting and removal instructions when migrating.

H1 — Best practices & trust checklist

H2 — User checklist

• Always download from the official domain: trezor.io.
• Verify checksums / PGP signatures where provided before running installers.
• Keep the firmware on the device and the host software updated.
• Beware of phishing: attackers may use fake "download" sites that look similar.

H3 — System administrators

On managed devices, prefer distributing signed Suite/Bridge packages and pinning versions in your package manager. For macOS and Linux, bridge artifacts are often packaged via OS-native formats (DEB/RPM/Homebrew) — check the official release channels before deploying at scale.

H1 — Official resources (10 authoritative links)

The HTML below includes 10 carefully selected official resources. Use these as your primary references and download sources.

H2 — How to cite these links

If you share this document, encourage recipients to verify domain names (trezor.io, github.com/trezor, data.trezor.io) and avoid copycat domains. Trust is earned by reproducible signatures and official release pages.