Hacker News Reader

Hacker News

Comment by wp381640 | Hacker News Reader

Full thread

wp381640

Microsoft product keys were base-24 with the following alphabet:

> B C D F G H J K M P Q R T V W X Y 2 3 4 6 7 8 9

they were 115 bits encoded in 24 characters

see also human-oriented base32 encoding:

https://philzimmermann.com/docs/human-oriented-base-32-encod...

which includes this nice trick:

> We have permuted the alphabet to make the more commonly occuring characters also be those that we think are easier to read, write, speak, and remember.

edit: to add, an interesting human-readable and memorable base52 alphabet that I've never found a use for is to use playing cards

View on HN

See also Bech32 which includes error correction and detection:

https://github.com/bitcoin/bips/blob/master/bip-0173.mediawi...

> Why not use an existing character set like RFC3548 or z-base-32? The character set is chosen to minimize ambiguity according to this visual similarity data, and the ordering is chosen to minimize the number of pairs of similar characters (according to the same data) that differ in more than 1 bit. As the checksum is chosen to maximize detection capabilities for low numbers of bit errors, this choice improves its performance under some error models.

Brings me back to the trusty old FCKGW-RHQQ2-YXRKT-8TG6W-2B7Q8

I wonder who owns that license. Some people allegedly used this as their password...

It was a special volume license key that didn't require online or phone activation, so presumably an OEM that got a release version couple weeks early

I never heard of this before. At first I thought it's some kind of joke with the "FCK" at the beginning.

> We have permuted the alphabet to make the more commonly occuring characters also be those that we think are easier to read, write, speak, and remember.

Basically they removed vowels (except for y, if it counts as one) as non-vowels often include a vowel in their sound. A fact reinforced while teaching my toddler daughter letters, words, and numbers. On top of that, they removed l/1(/i, and also o/0), m/n, s/5, z. Not sure why they removed z. Perhaps because of 2?

I'm not sure this is universal either, sound-wise. I suppose it does count for English. Because 7 ("zeven") and 9 ("negen") in Dutch get confused when spoken, some people say "zeuven" instead of "zeven".

> Not sure why they removed z. Perhaps because of 2?

My guess would be because of C, since Z can be pronounced as "zee"

> edit: to add, an interesting human-readable and memorable base52 alphabet that I've never found a use for is to use playing cards

The most famous example is Schneier's Solitaire [1]. It was a common encoding I liked to play with in HS classes even before reading Cryptonomicon. I still think about it sometimes when I read through a Duplicate Bridge story in that long syndicated newspaper column. (One of these days I will actually learn Bridge, maybe.)

[1] https://www.schneier.com/academic/solitaire/

> edit: to add, an interesting human-readable and memorable base52 alphabet that I've never found a use for is to use playing cards

I encountered something similar to this a while ago when watching a multiplayer mod of Ocarina of Time[0]. They use a string of inventory item symbols to denote the identity of the server to connect to. “Hook shot, hook shot, master sword, deku nut” is a whole lot easier to remember than a long string of ascii.

I guess it’d be something like a Base62 encoding.

[0]https://youtu.be/FLjIiVGPo_0

Microsoft's Base24 has a much saner alphabet as it avoids ambiguities between 5 and S, 7 and Z symbols while the alphabet suggested by the OP falls into pitfall.

It would make all sense to ensure that you don't have B and 8 in the same alphabet. Just as you don't want 1 and I, and 0 and O - pick any one of them, but not both.

Reply on news.ycombinator.com