Hello, I just wanted to put my two cents in, on the metal backup aspect. We make the Bitcoin Recovery Tag for a similar purpose. We use a fixed font, so using ' (apostrophe) or H/h are both acceptable. Most metal stamping tools are fixed width fonts.
You can see a picture here... [ https://cyphersafe.io/product/bitcoin-recovery-tag/ | https://cyphersafe.io/product/bitcoin-recovery-tag/ ] Thanks, Daniel -- Daniel Bayerdorffer, VP dani...@numberall.com Numberall Stamp & Tool Co., Inc. www.numberall.com Reuleaux Models www.reuleauxmodels.com CypherSafe www.cyphersafe.io PO BOX 187, Sangerville, ME 04479 USA TEL: 207-876-3541 FAX: 207-876-3566 From: "Craig Raw via bitcoin-dev" <bitcoin-dev@lists.linuxfoundation.org> To: "David A. Harding" <d...@dtrt.org> Cc: "Bitcoin Protocol Discussion" <bitcoin-dev@lists.linuxfoundation.org> Sent: Saturday, July 3, 2021 10:00:51 AM Subject: Re: [bitcoin-dev] BIP Proposals for Output Script Descriptors It's a consideration, not a serious concern. When I made the point around alphanumeric characters being similar to the path numbers, I was actually thinking of the output descriptor appearing in a fixed character width font, which I prefer as more appropriate for displaying hexidecimal values. In this case, the apostrophe provides more whitespace which makes the path easier to parse visually. It's difficult to reduce this to a mathematical argument, as is true for many UX considerations. Your example in fixed width here: [ https://gist.github.com/craigraw/fc98b9031a7e01e1bc5d75a77bdb72e5 | https://gist.github.com/craigraw/fc98b9031a7e01e1bc5d75a77bdb72e5 ] That said you make good arguments around the shell quoting and stamps for metal backups, and therefore I agree it is preferable to use the lowercase "h". Thanks for the detailed reply. Craig On Sat, Jul 3, 2021 at 12:11 PM David A. Harding < [ mailto:d...@dtrt.org | d...@dtrt.org ] > wrote: On Sat, Jul 03, 2021 at 10:35:48AM +0200, Craig Raw wrote: > There is a downside to using "h"/"H" from a UX perspective - taking up more > space Is this a serious concern of yours? An apostrophe is 1/2 en; an "h" is 1 en; the following descriptor contains three hardened derivations in 149 characters; assuming the average non-'/h character width is 1.5 en, the difference between 207 en and 208.5 en is barely more than half a percent. pkh([d34db33f/44h/0h/0h]xpub6ERApfZwUNrhLCkDtcHTcxd75RbzS1ed54G1LkBUHQVHQKqhMkhgbmJbZRkrgZw4koxb5JaHWkY4ALHY2grBGRjaDMzQLcgJvLJuZZvRcEL/1/*)#ml40v0wf Here's a direct visual comparison: [ https://gist.github.com/harding/2fbbf2bfdce04c3e4110082f03ae3c80 | https://gist.github.com/harding/2fbbf2bfdce04c3e4110082f03ae3c80 ] > appearing as alphanumeric characters similar to the path numbers First, I think you'd have to be using an awful font to confuse "h" with any arabic numeral. Second, avoiding transcription errors is exactly why descriptors now have checksums. > they make derivation paths and descriptors more difficult to read. The example descriptor pasted above looks equally (un)readable to me whether it uses ' or h. > Also, although not as important, less efficient when making metal > backups. I think many metal backup schemes are using stamps or punch grids that are fixed-width in nature, so there's no difference either way. (And you can argue that h is better since it's part of both the base58check and bech32 character sets, so you already need a stamp or a grid row for it---but ' is otherwise unused, so a stamp or grid row for it would be special). But even if people are manually etching descriptors into metal, we're back to the original point where we're looking at something like a 0.7% difference in "efficiency". By comparison, the Bitcoin Core issue I cited in my earlier post contains several examples of actual users needing technical support because they tried to use '-containing descriptors in a bourne-style shell. (And I've personally lost time to that class of problems.) In the worst case, a shell-quoting accident can cause loss of money by sending bitcoins to the descriptor for a key your hardware signing device won't sign for. I think these problems are much more serious than using a tiny bit of extra space in a GUI or on a physical backup medium. -Dave _______________________________________________ bitcoin-dev mailing list bitcoin-dev@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
_______________________________________________ bitcoin-dev mailing list bitcoin-dev@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
