5 ms·

Hexadecimal dumps of binary data are the worst of all worlds if used as keys/references. Hard to memorize, hard to type, look ugly, aren't compact. Better alte

Hexadecimal dumps of binary data are the worst of all worlds if used as keys/references. Hard to memorize, hard to type, look ugly, aren't compact. Better alternatives: Base64 without padding: compact. Grouped decimals: slightly less compact than hexadecimal, but extremely easy to type and pronounce. E.g. 577-467-341-467

contingencies 10y ago
Still better is grouped alphanumeric without potentially ambiguous characters (ie. generate number-1's but not letter-I's, generate number-0's but not letter-O's). I wrote a disambiguation library based upon the checksums present in IBAN @ https://github.com/globalcitizen/php-iban https://github.com/globalcitizen/php-iban .. it's surprising how accurate the mistranscription suggestions are. In general, pure-number systems are better if possible, but where you have issues squashing in enough data in suitably compact form, transitioning to alphanumeric is better. You can also consider the use prefix-based systems, either utilizing temporal epochs or node-specific prefixes, both of which can utilize readable aliases. Finally, for anything expecting human transcription, checksum systems are awesome!
- qznc 10y ago
  Afaik the Damm algorithm is the best for checksums https://en.wikipedia.org/wiki/Damm_algorithm https://en.wikipedia.org/wiki/Damm_algorithm
- saghm 10y ago
  > Still better is grouped alphanumeric without potentially ambiguous characters (ie. generate number-1's but not letter-I's, generate number-0's but not letter-O's) git license-plate?
gabrielhn 10y ago
Being able to easily copy/paste the string is important. The string should be a word so double clicking selects the full string. Maybe base62?
joallard 10y ago
Case-insensivity is important for some to be able to reliably remember a string. I won't easily retain the difference between 'b4dQbFs31' and 'b4DqBfs31'. Same thing when speaking it out loud. 'B four D capital Q B capital F s thirty-one' is way more convoluted and error-prone than 'B four D Q B F S thirty-one'. The best thing I've found that fits this criterion is Crockford's Base 32 [1], basically the extension of hex digits, removing letters ILOU. But Base 32 (case-insensitivity by proxy) constrains us to 5 bits, which is only a 20% reduction over the 4 bits of base 16. So instead of the 20 bits `1ab2f` we could express them with something like `1qm3`. Or we could be using words... [1]: http://www.crockford.com/wrmg/base32.html http://www.crockford.com/wrmg/base32.html
- eridius 10y ago
  Regarding Base 32, I love the justification used for removing U. I, L, and O all have potential confusion with digits, but U was removed because of "Accidental obscenity".
  - pitaj 10y ago
    That's actually pretty brilliant
  - mikeash 10y ago
    I once had a moment of panic after coming up with and shipping a custom scheme along these lines, when I realized there was a decent probability of generating accidental profanity. Afterwards I came up with a filter, and we spent a fun day filling it with every nasty word we could think of.
  - OJFord 10y ago
    I'm surprised it wasn't just "and all vowels" with the same reasoning, or at least 'a' (because I can more readily think of examples than for, say, 'e'). I suppose, though, there's an attraction in using b32 rather than b29... (Though I notice mid-word apostrophes are double-tap-selectable at least on macOS, so perhaps swapping 'a' for ''' would be advantageous, if more complicated to explain.)

contingencies 10y ago

Still better is grouped alphanumeric without potentially ambiguous characters (ie. generate number-1's but not letter-I's, generate number-0's but not letter-O's). I wrote a disambiguation library based upon the checksums present in IBAN @ https://github.com/globalcitizen/php-iban https://github.com/globalcitizen/php-iban .. it's surprising how accurate the mistranscription suggestions are. In general, pure-number systems are better if possible, but where you have issues squashing in enough data in suitably compact form, transitioning to alphanumeric is better. You can also consider the use prefix-based systems, either utilizing temporal epochs or node-specific prefixes, both of which can utilize readable aliases. Finally, for anything expecting human transcription, checksum systems are awesome!

qznc 10y ago
Afaik the Damm algorithm is the best for checksums https://en.wikipedia.org/wiki/Damm_algorithm https://en.wikipedia.org/wiki/Damm_algorithm
saghm 10y ago
> Still better is grouped alphanumeric without potentially ambiguous characters (ie. generate number-1's but not letter-I's, generate number-0's but not letter-O's) git license-plate?

gabrielhn 10y ago

Being able to easily copy/paste the string is important. The string should be a word so double clicking selects the full string. Maybe base62?

joallard 10y ago

Case-insensivity is important for some to be able to reliably remember a string. I won't easily retain the difference between 'b4dQbFs31' and 'b4DqBfs31'. Same thing when speaking it out loud. 'B four D capital Q B capital F s thirty-one' is way more convoluted and error-prone than 'B four D Q B F S thirty-one'. The best thing I've found that fits this criterion is Crockford's Base 32 [1], basically the extension of hex digits, removing letters ILOU. But Base 32 (case-insensitivity by proxy) constrains us to 5 bits, which is only a 20% reduction over the 4 bits of base 16. So instead of the 20 bits `1ab2f` we could express them with something like `1qm3`. Or we could be using words... [1]: http://www.crockford.com/wrmg/base32.html http://www.crockford.com/wrmg/base32.html

eridius 10y ago
Regarding Base 32, I love the justification used for removing U. I, L, and O all have potential confusion with digits, but U was removed because of "Accidental obscenity".
- pitaj 10y ago
  That's actually pretty brilliant
- mikeash 10y ago
  I once had a moment of panic after coming up with and shipping a custom scheme along these lines, when I realized there was a decent probability of generating accidental profanity. Afterwards I came up with a filter, and we spent a fun day filling it with every nasty word we could think of.
- OJFord 10y ago
  I'm surprised it wasn't just "and all vowels" with the same reasoning, or at least 'a' (because I can more readily think of examples than for, say, 'e'). I suppose, though, there's an attraction in using b32 rather than b29... (Though I notice mid-word apostrophes are double-tap-selectable at least on macOS, so perhaps swapping 'a' for ''' would be advantageous, if more complicated to explain.)