BitShares Forum
Main => General Discussion => Topic started by: Ray P. on July 17, 2015, 01:20:13 pm

Hello, members of bitsharestalk!
My name is Ray and lately I've finished an article about the history of ProofofWork, where I've tried to mention every algorithm that shifted the development and adoption of cryptocurrencies, such as:
 The Hashcash project
 Moderately hard, memorybound functions
 Secure hash algorithms (SHA2, SHA3)
 Scrypt and its versions
 X11
 Momentum
 Cuckoo Cycle
 CryptoNight
Of course, the tech under the Bitshares was mentioned as well
Another memorybound PoW function based on different principles was Momentum, implemented in BitShares. It is very simple:
For example, we want to sign data D. First we get H = Hash(D), where Hash()  is some cryptographic hashfunction
Let us find such values A and B that BirthdayHash(A + H) = BirthdayHash(B + H), with BirthdayHash() being a memorybound function, as scrypt.
Now, if Hash(H + A + B) < TargetDifficulty (read: begins with n zeros), than it is finished. Victory! Otherwise, go back to step 2.
I'll be happy if you take a look at it and share your thoughts in the comments!
The article is divided in two parts:
Part 1: https://bytecoin.org/blog/proofofwork/
Part 2: https://bytecoin.org/blog/proofofworkpart2/

Momentum was used in PTS (protoshares), not BTS :)

There are also multialgo schemes with several rounds of hashing with different hashing schemes