Re: My technique to split seed for cold storage

Quote from: dunand on August 17, 2017, 04:08:20 AM

I was looking for a technique to store a wallet seed. Because if somebody find your seed that person can steal the bitcoins. I found a way to split the seed in two parts for cold storage.
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Finally to obtain "encryption seed B" for each word you need to calculate index(word_seed) - index(word_encryption_a) % 2048.

Your method is similar to this one: XOR Seed Splitting: Theory and Practice[/quote]

I've looked into that one and Shamir's Secret Sharing, and the major drawback with regards to seeds is that the BIP-39 error detection is not very compatible with these methods. The problem is that you want the shared seeds to have BIP-39 error detection, and ideally to have the joined seed with BIP-39 error detection, too. But that is difficult to do because BIP-39 requires 32-bit data and BIP-39 adds extra bits.