What are the best backup methods for mnemonic words?

For maximum security, consider a combination of cold storage with Shamir's Secret Sharing, GPG encryption, and a multi-sig hardware wallet.

Feb 21, 2025 at 04:54 pm

Key Points

• Cold Storage with Shamir's Secret Sharing
• Seed Phrase Encryption with GPG
• Multi-Sig Hardware Wallets with Shamir's Secret Sharing
• Vault Storage with Trusted Entities

Backup Methods for Mnemonic Words

Cold Storage with Shamir's Secret Sharing

Description:

Shamir's Secret Sharing (SSS) is a cryptographic technique that divides a secret (mnemonic words) into multiple shares. To reconstruct the secret, a threshold number of shares must be combined.

Steps:

• Generate Shares: Use a SSS tool to generate multiple shares (e.g., 5 shares) from the mnemonic phrase.
• Store Shares Securely: Divide the shares across multiple cold storage locations (e.g., USB drives, paper wallets) in physically secure places.
• Reconstruction: To restore the mnemonic phrase, combine a threshold number of shares using the SSS tool.

Seed Phrase Encryption with GPG

Description:

GPG (GNU Privacy Guard) is a software package for encryption and digital signing. It can be used to encrypt the mnemonic phrase before storing it.

Steps:

• Install GPG: Download and install GPG software.
• Generate PGP Key: Create a PGP key for encryption and decryption.
• Encrypt Seed Phrase: Encrypt the mnemonic phrase using the PGP key and save the encrypted file to a secure location.
• Decryption: To recover the mnemonic phrase, import the PGP key and decrypt the encrypted file.

Multi-Sig Hardware Wallets with Shamir's Secret Sharing

Description:

Multi-sig hardware wallets allow for multiple parties to approve transactions. In combination with SSS, this provides redundant security for mnemonic words.

Steps:

• Create Multi-Sig Wallet: Purchase a multi-sig hardware wallet and set up a wallet with multiple owners (e.g., 2 out of 3).
• Generate SSS Shares: Divide the mnemonic phrase into multiple shares using SSS.
• Store Shares with Owners: Distribute the shares to the designated owners for safekeeping.
• Transaction Approval: When making a transaction, the wallet requires approval from a threshold number of owners.

Vault Storage with Trusted Entities

Description:

Vault storage involves storing the mnemonic words with a trusted third-party custodian in a physically secured facility.

Steps:

• Choose a Trusted Custodian: Research and select a reputable custodian with high-level security measures.
• Encrypt Seed Phrase: Encrypt the mnemonic phrase using a strong encryption algorithm (e.g., AES-256).
• Deposit in Vault: Deliver the encrypted seed phrase to the custodian and store it in their vault facility.
• Recovery: To retrieve the mnemonic phrase, contact the custodian and provide proof of identity to unlock the vault.

FAQs

What is the most secure method for storing mnemonic words?

Answer: The most secure method depends on individual circumstances but generally involves a combination of methods, such as cold storage with SSS, GPG encryption, and multi-sig hardware wallets.

Why is Shamir's Secret Sharing considered so secure?

Answer: SSS provides redundancy by distributing the secret across multiple shares, making it difficult to compromise the entire secret even if some shares are lost or stolen.

What are potential risks associated with vault storage?

Answer: Potential risks include the custodian's security measures being compromised, loss or damage of the vault, and trust issues with the custodian.

How can I protect my mnemonic words from phishing attacks?

Answer: Never share your mnemonic words with anyone, including exchange support or wallet developers. Always verify the source of any requests for your seed phrase.

How often should I backup my mnemonic words?

Answer: It is recommended to backup your mnemonic words immediately after generating them and regularly thereafter, especially if you are making changes to your wallet or recovering a wallet from backup.