[WO] Permutations of precious washers, and recovery of losses thereof
ROFL !!! ... Tomorrow I will go buy and make my own! <3
But what happens if you lose 1 or the order of them?
... I guess its a guessing game then...O(n!) for the order. If you totally lose the order, it depends on how many of those precious washers there are to permute.
12! is only 479,001,600, easy for a computer to bruteforce search. 24! is an awful lot bigger, and would require over 279 work to bruteforce. For BIP 39 (not Electrum), the checksum bits can help to optimize the work that you do when searching; but you will still need to do the search.
(For comparison, the ordering of a deck of cards has 52! permutations, about 2225.)
If you lose only a part of the ordersay, if just a few washers fall off the end and scatter across the floorthen recovery will accordingly be easier.
What about dealing with a "losing one" scenario that STRF had mentioned?
You suggesting that "cool" people do not have the right (if that's an appropriate word choice?) to lose any of those 12, 18 or 24 washers?
You suggesting that "cool" people do not have the right (if that's an appropriate word choice?) to lose any of those 12, 18 or 24 washers?
Each washer that you totally lose means 2048 trial-and-error attempts to replace it, if you still know the ordering of all washers (including the blank spots). Thats exponential, to the power of the number of lost washers.
Losing one is easy to fix!
If you lose up to 4 washers, it should be feasible to recover your coins with a home PC and some patience. If you lose 6, recovery will be awfully expensive; it may still be worthwhile for a whale wallet. If you lose 7 or 8, I would guess that the NSAs supercomputers could still recover your coinsmaybe. If you lose 12, recovery will be far beyond the combined capability of all computers on earth; that is why 12 words is the minimum seed length.
I myself use 24-word seeds, for to protect even against superintelligent space aliens with star-sized computers and a few billion years of spare time. But note that Bitcoins public-key security level is the same level as a 12-word seed, i.e. 128 bits. (Bitcoin uses 256-bit elliptic curve keys, but brute force is not the best known way to attack that class of cryptography; this is many orders of magnitude faster.)
If you lose the ordering and lose some washers, theneh, good luck, LOL!