What is BIP39

[letteredhub]

Since I became a member of the bitcointalk community and have been taking time to read through some few posts I have been seeing some posts whose questions are wallet related questions, and going through a few comments in those posts they made mention of something "BIP39 seed phrase", and I have been wanting to know what is this BIP39 and it's significant or is it just an acronym about a wallet?

[Charles-Tim]

Read more about it from here: https://github.com/bitcoin/bips/blob/master/bip-0039.mediawiki

To know more about hierarchical deterministic (HD) wallet: https://github.com/bitcoinbook/bitcoinbook/blob/develop/ch05.asciidoc

BIP39 is the mnemonic code or seed phrase that was introduced which can be used to generate keys and addresses which gives rise to child keys. Before in non HD wallets, only the individual child keys are used individually as backup, unlike the 12 to 24 words (the seed phrase) that can be used now to generate the child keys.

[o_e_l_e_o]

BIP39 is the mnemonic code or seed phrase that was introduced which can be used to generate keys and addresses which gives rise to child keys.

A small correction - BIP39 did not introduce this concept. Seed phrases existed for a number of years before BIP39 was published. The aim of BIP39 was to standardize the process of generating the seed phrase and turning the seed phrase in to a wallet. It has largely achieved that given that the majority of wallets now follow BIP39, but there remains one notable exception being Electrum seed phrases (which predate BIP39 seed phrases).

[Pmalek]

What o_e_l_e_o said about Electrum being an exception shouldn't put you off from using that software if you want to. There is nothing wrong with Electrum or its native seeds. In fact, they have slightly more entropy (call it security) than a BIP39 seed. Either standard is fine. The difference is you have fewer options to recover an Electrum-native seed outside of Electrum, while BIP39 seeds are accepted by most wallets.

Electrum seeds have one advantage when you recover a wallet (in Electrum). By entering your seed words, the software automatically knows what type of wallet it needs to recover (legacy, nested, or native segwit). With a BIP39 seed, you need to point the software towards the correct derivation path and provide information about the type of addresses you want to recover. If you do it wrongly, the software can recover what looks like an empty wallet, making you think you don't have any coins or you made a mistake backing up your recover phrase. 

[DireWolfM14]

Make sure to learn the differences between the common uses of the term "Bip39."  As has been pointed out, the mnemonic seed is called a "Bip39 seed phrase," but you'll also run into the term "Bip39 passphrase."  The two are not the same; a Bip39 passphrase is an extension to a Bip39 seed phrase.

[nc50lc]

-snip- , and going through a few comments in those posts they made mention of something "BIP39 seed phrase", and I have been wanting to know what is this BIP39 and it's significant or is it just an acronym about a wallet?

If you're wondering what "BIP" means, yes it's an acronym but not of a wallet.
It's one of the many "Bitcoin Improvement Proposals" (github link), the number next to it is set by the author, usually in numeric order or already reserved.

So if you see another "BIP-XX" in a comment, the author is talking about a proposal from the list above.

[witcher_sense]

Since I became a member of the bitcointalk community and have been taking time to read through some few posts I have been seeing some posts whose questions are wallet related questions, and going through a few comments in those posts they made mention of something "BIP39 seed phrase", and I have been wanting to know what is this BIP39 and it's significant or is it just an acronym about a wallet?

For the sake of simplicity, let's assume that you use a long password consisting of multiple words separated by whitespace to access your "account" in the blockchain. But the password itself is not enough to communicate with the blockchain, you need a piece of software or a wallet to facilitate this task. The magic is that your "password" or seed phrase is universally accepted by all these different types of wallets, which means you can use almost whatever wallet you wish to interact with the bitcoin blockchain. At the very least, it is very convenient for the end user since he doesn't need to care for compatibility issues. What makes compatibility possible in the first place? BIP39. It describes an approach to key creation, how and why wallets should interpret the set of words you feed them, and wallets follow it to be compatible with the standard and one another.

[Saint-loup]

Read more about it from here: https://github.com/bitcoin/bips/blob/master/bip-0039.mediawiki

To know more about hierarchical deterministic (HD) wallet: https://github.com/bitcoinbook/bitcoinbook/blob/develop/ch05.asciidoc

BIP39 is the mnemonic code or seed phrase that was introduced which can be used to generate keys and addresses which gives rise to child keys. Before in non HD wallets, only the individual child keys are used individually as backup, unlike the 12 to 24 words (the seed phrase) that can be used now to generate the child keys.

Actually before BIP39 there was BIP32 https://github.com/bitcoin/bips/blob/master/bip-0032.mediawiki
BIP32 has been created in February 2012 while BIP39 has been created in September 2013 precisely. And it's BIP32 which introduced/standardized Hierarchical Deterministic Wallets, BIP39 only allowed them to be more easily usable and memorizable by humans. But Bitcoin Core still doesn't use BIP39 seeds for example, only BIP32 ones in WIF format.

[bitmover]

Read more about it from here: https://github.com/bitcoin/bips/blob/master/bip-0039.mediawiki

To know more about hierarchical deterministic (HD) wallet: https://github.com/bitcoinbook/bitcoinbook/blob/develop/ch05.asciidoc

BIP39 is the mnemonic code or seed phrase that was introduced which can be used to generate keys and addresses which gives rise to child keys. Before in non HD wallets, only the individual child keys are used individually as backup, unlike the 12 to 24 words (the seed phrase) that can be used now to generate the child keys.

Just to add to this answer,  there are many bip 39 translations which can be seen here:

https://github.com/bitcoin/bips/tree/master/bip-0039

The portuguese version was a community effort from the bitcointalk.org portuguese  board, and you can see many usernames of this forum in the contributors of this github repository.

[Sarah Azhari]

Actually before BIP39 there was BIP32 https://github.com/bitcoin/bips/blob/master/bip-0032.mediawiki
BIP32 has been created in February 2012 while BIP39 has been created in September 2013 precisely. And it's BIP32 which introduced/standardized Hierarchical Deterministic Wallets, BIP39 only allowed them to be more easily usable and memorizable by humans. But Bitcoin Core still doesn't use BIP39 seeds for example, only BIP32 ones in WIF format.

is BIP39 is a development from BIP32?, if yes, why they don't continue their development about vulnerability or weakness which was shown by electrum?.

A fixed wordlist is still required. Following our recommendation, BIP39 authors decided to derive keys and addresses in a way that does not depend on the wordlist. However, BIP39 still requires the wordlist in order to compute its checksum, which is plainly inconsistent, and defeats the purpose of our recommendation. This problem is exacerbated by the fact that BIP39 proposes to create one wordlist per language. This threatens the portability of BIP39 seed phrases.

BIP39 seed phrases do not include a version number. This means that software should always know how to generate keys and addresses. BIP43 suggests that wallet software will try various existing derivation schemes within the BIP32 framework. This is extremely inefficient and rests on the assumption that future wallets will support all previously accepted derivation methods. If, in the future, a wallet developer decides not to implement a particular derivation method because it is deprecated, then the software will not be able to detect that the corresponding seed phrases are not supported, and it will return an empty wallet instead. This threatens users funds.

https://electrum.readthedocs.io/en/latest/seedphrase.html

[hosseinimr93]

why they don't continue their development about vulnerability or weakness which was shown by electrum?.

There is no vulnerability in BIP39 seed phrase and that's safe enough.
Electrum's seed phrase includes a version number which makes each seed phrase generate only 1 type of addresses. Unlike electrum's seed phrase, BIP39 seed phrase doesn't include a version number and that's why electrum developers don't like BIP39 seed phrase.

[o_e_l_e_o]

Just to add to this answer,  there are many bip 39 translations which can be seen here:

It is highly recommend not to use a local wordlist since the majority of wallets only support the English wordlist.

This is another drawback of BIP39, in that you must know the wordlist used. Electrum seeds can be used with an unknown wordlist.

is BIP39 is a development from BIP32?, if yes, why they don't continue their development about vulnerability or weakness which was shown by electrum?

The weaknesses shown by Electrum were apparent before the creation of BIP39. The developers of BIP39 decided they were not severe enough to need addressed, but now we frequently see users unable to track down their wallets due to unknown derivation paths or script types.

And now that BIP39 is so ubiquitous, they cannot address them without introducing an entire new seed phrase system which would be incompatible with existing seed phrases.

[bitmover]

Just to add to this answer,  there are many bip 39 translations which can be seen here:

It is highly recommend not to use a local wordlist since the majority of wallets only support the English wordlist.

I understand your point of view, and I use english keywords as well.

However,  any keyword list from any language can just be "translated" to english just by converting the respective word number to the english equivalent.

some good tools such as ian coleman use it was well.
https://iancoleman.io/bip39/#portuguese

[o_e_l_e_o]

However,  any keyword list from any language can just be "translated" to english just by converting the respective word number to the english equivalent.

That's not how it works.

It is the words themselves, not the bit string they represent, which is fed in to PBKDF2 in order to generate your seed number, master keys, and entire wallet. Translating the words will result in an entirely different wallet being generated, even if the words represent the same underlying entropy.

You can try this yourself in Ian Coleman. Open it up and generate a seed phrase in any language. Then click "Show entropy details". Then choose a different language. It will "translate" your seed phrase while keeping the same word index numbers, but the resulting keys and addresses will be completely different.

[Sarah Azhari]

Just to add to this answer,  there are many bip 39 translations which can be seen here:

It is highly recommend not to use a local wordlist since the majority of wallets only support the English wordlist.

Seem like, Electrum wallet is supported for that 10 BIP39 different language lists ( I tried it and got the correct address). so we haven't to worry about using the local language list.

I just watch my local list - https://github.com/bitcoin/bips/pull/621
that isn't updated.

[NotATether]

Just to add to this answer,  there are many bip 39 translations which can be seen here:

It is highly recommend not to use a local wordlist since the majority of wallets only support the English wordlist.

Seem like, Electrum wallet is supported for that 10 BIP39 different language lists ( I tried it and got the correct address). so we haven't to worry about using the local language list.

I just watch my local list - https://github.com/bitcoin/bips/pull/621
that isn't updated.

Wordlists don't go inside BIP39 anymore. They go into a separate standard that is called "WLIPs" (WordList Improvement Proposals).

For now, the author(s) of BIP 39 have decided not to accept any further word lists into BIP 39 itself, and encourage adding new ones to the WLIPs repo here: https://github.com/p2w34/wlips

That repo seems to have only english and polish lists for now, but a lot of the proposed wordlists are missing from there, and they can be seen in the pull request I linked.

[o_e_l_e_o]

Seem like, Electrum wallet is supported for that 10 BIP39 different language lists ( I tried it and got the correct address). so we haven't to worry about using the local language list.

Again, that's not how it works.

If you import a non-English BIP39 seed phrase in to Electrum, it will show the error "Unknown wordlist". Because the wordlist is unknown, Electrum is unable to tell you if any of the words are incorrect or if the checksum is invalid. Since it is the words themselves which are fed in to PBKDF2, then if everything is correct then yes, you will still generate the same wallet. But you lose all the safety of unique words and a checksum, since these things cannot be checked without knowing the wordlist being used.

And, as always, Electrum have never offered any guarantee that they will continue to support BIP39 seed phrases.

[bitmover]

Seem like, Electrum wallet is supported for that 10 BIP39 different language lists ( I tried it and got the correct address). so we haven't to worry about using the local language list.

Again, that's not how it works.

If you import a non-English BIP39 seed phrase in to Electrum, it will show the error "Unknown wordlist". Because the wordlist is unknown, Electrum is unable to tell you if any of the words are incorrect or if the checksum is invalid. Since it is the words themselves which are fed in to PBKDF2, then if everything is correct then yes, you will still generate the same wallet. But you lose all the safety of unique words and a checksum, since these things cannot be checked without knowing the wordlist being used.

And, as always, Electrum have never offered any guarantee that they will continue to support BIP39 seed phrases.

Curiously, there are some different wordlists in electrum repo.

They are not the same in the BIP39 wordlists, but there are many languages.
https://github.com/spesmilo/electrum/tree/master/electrum/wordlist

Some of them are somehow related to Monero Projects (like the portuguese one, which has a text in the start "# Copyright (c) 2014, The Monero Project")

[o_e_l_e_o]

Curiously, there are some different wordlists in electrum repo.

You can see why here: https://github.com/spesmilo/electrum/issues/7956. They are not used.

Some of them are somehow related to Monero Projects (like the portuguese one, which has a text in the start "# Copyright (c) 2014, The Monero Project")

The Portuguese one is a good example - you'll notice it has 1626 words. This is the same number of words as old style Electrum seed phrases, which also used an English word list with 1626 words: https://github.com/spesmilo/electrum/blob/18cf546aab7d1a4d122a85ae2b49935cf64c9510/electrum/old_mnemonic.py#L31

Such phrases have not been used in many years, however.

[nc50lc]

-snip-
Curiously, there are some different wordlists in electrum repo.

...and to satisfy that curiosity, it'll still work if they decided to use it even if the words aren't included in BIP39 wordlist nor for having 1626 words.

Electrum's seed doesn't actually need a fixed wordlist, you can even edit the english.txt with your own set of words
and it will produce a valid seed (given that there's enough to produce a valid one).
e.g. (SegWit - Can be imported to Electrum):

Code:

banana110206 banana110312 banana021413 banana061112 banana030713 banana130608 banana020311 banana010311 banana010306 banana101112 banana020705 banana091106