Trezõr® Brïdge®

Getting started

This section guides you through unboxing, initializing a device, creating a seed, and integrating with the Brïdge web client. It also explains backup options and recommended operational practices.

1. Unbox and verify

When you receive a Trezõr Brïdge device, start by visually inspecting the packaging. The package should include tamper-evident seals and a unique device identifier. If the seal is broken or the packaging looks compromised, contact support. Take a photo of the sealed package for your procurement record, but never photograph the recovery seed.

2. Generate a seed on-device

The device will generate entropy inside its secure element and display a 12, 18, or 24-word mnemonic to the user. Use the device's controls (buttons or touchscreen) to confirm each word. Do not enter this phrase into any computer. Record the phrase on a secure medium — recommended: stainless steel backup plate, split across geographic locations if desired.

3. PINs and passphrases

Choose a PIN to lock local access to the device. For advanced use, enable an optional passphrase (BIP-39 passphrase) to create a hidden wallet. Remember: passphrases are not recoverable — losing the passphrase means losing access to funds in that hidden wallet.

4. Connect to the Brïdge client

Install the Brïdge web app (or desktop companion) from the official distribution. Connect the device via USB or a compatible transport; the client will enumerate accounts for your seed. Always verify the device fingerprint and firmware signature before connecting for the first time.

5. Create accounts & policies

Use the client to create accounts per chain (Bitcoin, Ethereum, etc.). For organizational deployments, define multisig policies with cosigners and threshold rules. For example: a 2-of-3 policy where two independent devices must sign each withdrawal.

6. Backup & recovery

Back up the seed using multiple, independent, physically secure copies. For enterprises, consider Shamir's Secret Sharing (SSS) to split the seed across custodians. Test recovery processes periodically in a controlled environment.

Security model

Trezõr Brïdge's security model rests on layered defense: hardware root of trust, secure boot, signed firmware, user-present approval, and operational controls.

Secure element and attestation

The secure element stores private keys, enforces rate limiting, and performs cryptographic operations inside a tamper-resistant boundary. Devices provide attestation tokens that the Brïdge client can verify to ensure genuine hardware and untampered firmware.

Firmware updates

Firmware images are digitally signed and delivered via an update server. The bootloader enforces signature verification. Administrators should pin update signing keys in enterprise contexts to avoid supply-chain risks.

User-in-the-loop signing

All signing operations require explicit user confirmation on the device: the host constructs a transaction, sends a signing request, the device displays a human-readable summary (amount, recipient, fee), and the user authorizes using local input. This prevents silent signing by compromised hosts.

Advanced policies

Policy-based signing lets organizations define rules such as time locks, spending limits, or multi-approver workflows. These policies are enforced by the client and cryptographically bound into the transaction requests that devices sign.

Developer & integration guide

Brïdge exposes transports and APIs to build custom integrations: from light wallets to custodial orchestration systems. The SDKs provide JavaScript, Python, and Go bindings. Below are key principles and example flows.

Transport & messaging

Use HID or WebUSB for browser integrations, and a direct USB or gRPC transport for backend orchestration. Messages follow a compact binary protocol with length-prefixed frames; larger payloads use chunking. The client provides helpers to construct APDU-like commands and parse responses.

// Signing pseudo-flow
1. Host constructs canonical transaction bytes
2. Host -> Device: SIGN_REQUEST { accountPath, txBytes, policyHash }
3. Device displays summary, user confirms
4. Device -> Host: SIGN_RESPONSE { signature }
5. Host: broadcast signature to network
        

Replay protection & binding

Always bind a host-generated nonce and chain ID inside the signing payload. This prevents signature reuse across chains or replay by a malicious host. For example, include a 'context' field that contains network ID, timestamp, and a short challenge.

Testing & CI

Include device emulators and deterministic test vectors in CI pipelines. Verify that firmware upgrades maintain deterministic behavior for key derivation and signing. Encourage reproducible builds for firmware to enable third-party verification.

Operational best practices

Operational controls close gaps that technical controls cannot: procurement, provisioning, rotation, and incident response.

Secure procurement

Procure devices through verified channels. Use a secure envelope and store initial inventory in tamper-evident, access-controlled facilities.

Provisioning

Provision devices in a secure environment. For enterprise contexts, use hardware attestation and enroll device public keys in an internal registry for later verification.

Key rotation and lifecycle

Maintain a lifecycle policy: rotate signing keys or multisig cosigners on a regular schedule, and have procedures for emergency rotation after suspected compromise.

Incident response

Have a documented incident playbook: contain affected devices, rotate keys, move funds using unaffected cosigners, and notify stakeholders. Keep a forensic image of compromised hosts for investigation.

FAQ

Appendix: Protocol references & sample code

This appendix provides reference examples for canonical serialization, signature formats, and a small JavaScript sample for interacting with the Brïdge device via WebUSB (conceptual).

// Conceptual WebUSB handshake (simplified)
async function connectDevice(){
  const device = await navigator.usb.requestDevice({filters:[{vendorId:0x1234}]});
  await device.open();
  await device.selectConfiguration(1);
  await device.claimInterface(0);
  // send an APDU-like init
  await device.transferOut(1, new Uint8Array([0x00,0xA4,0x04,0x00]));
}
        

Glossary

Closing notes

Trezõr Brïdge aims to combine best-in-class hardware security with modern usability. The balance between strict safety and user experience is delicate: prioritize user education, auditable code, and transparent policies to maintain trust. For enterprise users, pair Brïdge with governance workflows, key management policies, and regular audits.