Users who have used the wallet know that before using the wallet, you will be asked to back up 12 words. During the backup period, screenshots are not allowed, and it is constantly emphasized that these 12 words are very important. It is best to back them up in a physical way. anyone.

For ordinary users, if you just blindly emphasize the conclusion of the importance of mnemonics to them without telling the reasons behind it, it will be difficult to mobilize the underlying motivation of people, and it is very likely that they will forget the mnemonic in a few days The importance of words (I have seen many disasters in the group calling myself bankrupt because of the loss of mnemonics).

As the security ambassador of Cheetah Blockchain, Xiaobao will come to talk to you today about the mnemonic and the story behind it.

secondary title

Multiple account requirements

Let’s take a real-life example as an analogy. Generally speaking, we have many accounts for the money we store in the bank. Some accounts are used to buy pancakes and fruit change accounts, some are used for corporate business accounts, and some are large deposits. asset account. These accounts can be handled with only one ID card. We can log in many accounts in online banking with one ID card. If the bank card is accidentally lost, it can also be reissued through the ID card. In real life, identity cards are extremely important.

secondary title

Reduce the probability of error

secondary title

privacy protection

Due to the open nature of the blockchain public chain, anyone can check all the transfer records on the chain. If there are too many income and expenses associated with the same account, some clues can be found in the end, and you and some transactions will be sent to you. Therefore, for the sake of privacy, many of our privacy businesses usually create new accounts for transactions.

In order to solve the above problems, smart developers proposed the Bip39 protocol. The full name of the Bip39 protocol is Bitcoin protocol, which was originally proposed by the developers of the Bitcoin community, and later recognized by other mainstream blockchain projects, and then became the consensus and norm of the entire industry.

The core of the BIP39 protocol is to determine your own account by 12 words. 12 words will generate a large seed, and a number is selected from the 256th power. Since the randomly generated number is very large, it is not used at all. Worried that the generated 12 words will be repeated.

The account generated by 12 words is fixed, and the 12 words obtained can create countless private keys, public keys and addresses.

Expressing the relationship between them with a formula can be written as follows:

Private key = Algorithm 1 (mnemonic)

public key = algorithm 2 (private key)

Public Key Hash = Algorithm 3 (Public Key)

so,

so,Address = Algorithm 4 (Algorithm 3 (Algorithm 2 (Algorithm 1 (mnemonic))))

Of course, Algorithms 1, 2, 3, and 4 are all public algorithms.

Through the guarantee of cryptography, the order and content of the generated words cannot be repeated. Through the mnemonic, we can generate any public chain address, and we can generate as many addresses as we need.

You can generate a mnemonic or view the private key, public key, and address corresponding to the mnemonic through https://iancoleman.io/bip39/.

Moreover, the BIP39 protocol supports almost all public chains.

Xiaobao did an experiment with Xiaobao's private Matemask mnemonic:

first level title

Understanding mnemonics from a technical perspective

From a technical point of view, BIP39 uses a sequence of 12 mnemonic words to create a random seed as a BIP32 seed (usually in hexadecimal) through the PBKDF2 and HMAC-SHA512 functions.

Compared with the BIP32 protocol, we can see which one is more friendly for backup:

//BIP32 random number seed

090ABCB3A6e1400e9345bC60c78a8BE7  

//BIP39 mnemonic seed

candy maple cake sugar pudding cream honey rich smooth crumble sweet treat

secondary title

generate mnemonic

secondary title

Seed derived from mnemonic

This process uses the Key stretching function, which is used to enhance the security of weak keys. PBKDF2 is one of the commonly used key stretching algorithms.
The basic principle of PBKDF2 is to use a random function (such as HMAC function), take the mnemonic plaintext and salt value as input parameters, and then repeat the operation to finally generate a longer (512-bit) key seed. This seed then builds a deterministic wallet and derives its keys.
The key stretch function takes two parameters: mnemonic and salt. Salt can increase the difficulty of brute-forcing. salt by constant string"mnemonic"first level title

Mnemonic Phrase Drives Blockchain Popularity

With the mnemonic, we can create a new account for any transaction, and the money in the account can also be freely transferred.

In the blockchain world, you only need to remember 12 simple mnemonic words to indirectly remember all the assets on the blockchain, which is as convenient and efficient as an ID card in real life.

With the mnemonic, the use cost of ordinary users is greatly reduced, and it is very user-friendly in terms of experience, which shortens the distance between the blockchain and the general public, and at the same time satisfies the privacy issues of high-end users.It can be said that the BIP39 protocol has greatly promoted the popularization of the blockchain.

Some people may say, "I hate English the most. Asking me to memorize 12 English words is killing me!"

I will not comment on these users, but smart developers have already thought of this. The BIP39 protocol currently supports several major languages, such as English, Japanese, Spanish, Korean, French, and of course Chinese. So you can use 12 Chinese characters as mnemonics.

If you don’t even bother to memorize 12 Chinese characters, then I can only say, benefactor, the blockchain world is really not for you, just find a good person and marry.

Of course, everything has two sides. Although the mnemonic brings a lot of convenience, it also creates another security risk, that is, once the 12 words are leaked or obtained by hackers, the mnemonic is an unencrypted private key,secondary title

Here are some suggestions for you:

(1) The mnemonic is the lifeblood of your digital world, and you cannot tell others if you die.

(2) Be sure to verify the correctness of the backup mnemonic multiple times. Once one or two letters are copied incorrectly, it will bring great difficulties to retrieve the correct mnemonic in the future.

(3) It is best to use the human brain to memorize the mnemonic. If you are afraid of forgetting it, back it up in a physical way.

Ratingtoken official website: https://www.ratingtoken.io/?from=z