Some cryptocurrencies use fixed values in some positions in the resulting hash, like a fixed amount of initial zeros. What fixed positions and fixed values are Facebook Diem using?
4
-
1$\begingroup$ Are you speaking about proof-of-work? $\endgroup$– IevgeniCommented Jul 5, 2021 at 13:36
-
$\begingroup$ I wan't to know more about how secure it is. The more fixed values the less variation and less security in the algorithm. $\endgroup$– David JonssonCommented Jul 5, 2021 at 13:49
-
$\begingroup$ @Ievgeni Yes this is what is commonly called proof-of-work. I am interested in general how proof-of-work limits the hash function. $\endgroup$– David JonssonCommented Jul 5, 2021 at 15:05
-
1$\begingroup$ Actually the leading zeros are more of a side-effect. Mostly it's just that the hash value must be less than a specific value (like $2^{256}/difficulty$). Of course that results in the first digits beeing zero. (but allows for smoother steps) $\endgroup$– jjjCommented Jul 11, 2021 at 23:06
Add a comment
|
1 Answer
$\begingroup$
$\endgroup$
2
As far as I understood, you are speaking about proof-of-work. But contrarily to what your question said :
Some Crypto currencies use fixed values in some positions in the resulting hash.
It corresponds to proof-of-work. The idea is the following, to guarantee that people which valid a transaction are "real", the have to solve a puzzle, which is basically a preimage of $\{0\}^\lambda\times\{0,1\}^{256-\lambda}$ for a specific hash function (parametrized by the transaction) (you can look this to have more precision : Complexity of Hash mining/signing)
But not all the cryptocurrency are using proof-of-work. And in particular, as far as I understood it's not the case for DIEM
Citation in the white-paper: "Second, this class of consensus protocols enables high transaction throughput, low latency, and a more energy-efficient approach to consensus than “proof of work” "
Link : https://www.diem.com/en-us/white-paper/#the-libra-blockchain
Citation in "The Libra Blockchain" paper:
"To do this, we plan to gradually transition to a proof-of-stake":
https://diem-developers-components.netlify.app/papers/the-diem-blockchain/2020-05-26.pdf
-
$\begingroup$ The second link does not point to a page anymore. $\endgroup$ Commented Mar 11, 2022 at 17:15
-
$\begingroup$ @DavidJonsson I didn't find anymore the whitepaper. But I've added another relevant link. $\endgroup$– IevgeniCommented Mar 11, 2022 at 19:32