If you have a valuable amount of cryptocurrency then one of the safest ways to store it is on an industry standard BIP39 hardware wallet and use the optional passphrase feature.
Most modern cryptocurrency wallets use a protocol known as BIP39 which generates a set of easy to remember words during the wallet initialisation process. These words are commonly referred to as the wallet’s ‘seed phrase’ or ‘recovery seed’ and usually consist of either 12 or 24 words that should be safely stored as they enable you to recover your wallet if it becomes inaccessible.
Additionally, BIP39 allows for the creation of an optional passphrase that generates an additional hidden wallet that provides an extra layer of security. This hidden wallet will only be accessible if the passphrase is known and will remain hidden at all other times. If the passphrase is not known only the regular wallet will be visible and accessible. This is an extremely handy and powerful feature to securely store your funds. However, if this feature is used it is essential that the passphrase is remembered as losing it will result in loss of access to the hidden wallet and its contents.
Using the BIP39 passphrase feature means
- The contents of the hidden wallet remain secure even if the seed phrase is discovered
- Storing a small amount of funds to the main wallet should be sufficient to distract an attacker
- There is literally no way to brute force a hidden wallet – the mathematics for success are 1 in 2^512.