📅 Original date posted:2021-08-29
📝 Original message:On Thursday, August 19th, 2021 at 1:02 PM, ts via bitcoin-dev <bitcoin-dev at lists.linuxfoundation.org> wrote:
> > In any case --- the last 5 characters of a bech32 string are already a human-readable 5-digit code, with fairly good properties, why is it not usable for this case?
Side note: it's actually the last six characters.
>
> Well, because
>
> a) most people don't know that
>
> b) it is specific to bech32
>
> c) it is not easily readable being the last digits of a long address (although this could be
I think this is a misconception. For the purpose of verifying that you have the *right* address (rather than just a valid one), the checksum, or even the knowledge that a checksum is present, is completely irrelevant.
In honestly-generated addresses, every character except the prefix (the ~2 first characters for P2PKH and P2SH, and the ~4 first characters for BIP173/BIP350 native segwit addresses) has exactly the same amount of entropy. Instead of adding say a 4 character code, just tell people to compare any 4 characters of their choosing. Or more - I would hope people are already comparing (much) more than 4 characters already.
It doesn't matter if the characters being compared are checksum characters or data characters. In honestly-generated addresses, both are equally random.
Adding a special 4 character "external" checksum IMO would instead encourage people to perhaps just compare those 4 characters instead of the rest (or at least, focus mostly on those). That could easily worsen how well comparisons are done in practice...
Cheers,
--
Pieter
Pieter Wuille [ARCHIVE] /
npub1tj…jtl6r
2023-06-07 22:58:09
in reply to nevent1q…vvqx
Author Public Key
npub1tjephawh7fdf6358jufuh5eyxwauzrjqa7qn50pglee4tayc2ntqcjtl6rPublished at
2023-06-07 22:58:09Event JSON
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"content": "📅 Original date posted:2021-08-29\n📝 Original message:On Thursday, August 19th, 2021 at 1:02 PM, ts via bitcoin-dev \u003cbitcoin-dev at lists.linuxfoundation.org\u003e wrote:\n\n\u003e \u003e In any case --- the last 5 characters of a bech32 string are already a human-readable 5-digit code, with fairly good properties, why is it not usable for this case?\n\nSide note: it's actually the last six characters.\n\n\u003e\n\u003e Well, because\n\u003e\n\u003e a) most people don't know that\n\u003e\n\u003e b) it is specific to bech32\n\u003e\n\u003e c) it is not easily readable being the last digits of a long address (although this could be\n\nI think this is a misconception. For the purpose of verifying that you have the *right* address (rather than just a valid one), the checksum, or even the knowledge that a checksum is present, is completely irrelevant.\n\nIn honestly-generated addresses, every character except the prefix (the ~2 first characters for P2PKH and P2SH, and the ~4 first characters for BIP173/BIP350 native segwit addresses) has exactly the same amount of entropy. Instead of adding say a 4 character code, just tell people to compare any 4 characters of their choosing. Or more - I would hope people are already comparing (much) more than 4 characters already.\n\nIt doesn't matter if the characters being compared are checksum characters or data characters. In honestly-generated addresses, both are equally random.\n\nAdding a special 4 character \"external\" checksum IMO would instead encourage people to perhaps just compare those 4 characters instead of the rest (or at least, focus mostly on those). That could easily worsen how well comparisons are done in practice...\n\nCheers,\n\n--\nPieter",
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