Bitcoin Forum

Alternate cryptocurrencies => Altcoin Discussion => Topic started by: PixL on May 16, 2019, 08:53:37 AM



Title: PoW Algorithms
Post by: PixL on May 16, 2019, 08:53:37 AM
Hi everyone,

For a study purpose, I would like to know which algorithm are compatible with the Proof of Work.
If you know an existing list of it or if you know some of it, your knowledge would be much appreciated.

Thank you for your help,

PixL


Title: Re: PoW Algorithms
Post by: bob123 on May 16, 2019, 09:03:58 AM
This is not that easy to answer.

You need to elaborate what exactly you want to know.

PoW just describes some soft of a crystallographic puzzle which has to be solved.
There are 2 types of PoW:
  • Challenge-Response
  • Solution-verification

Moreover, these variants can be either CPU-bound, memory-bound or network-bound.


If you are now talking about the 2nd type of PoW with CPU-bound functions (like it is the case in bitcoin), you can basically use any hashing algorithm (is this what you meant by "which algorithm"?) you want.


PoW in a centralized environment (e.g. network login via RADIUS server etc.) always uses challenge-response.
Obviously this is completely different from bitcoin mining.

So you really need to be more detailed about what you want to know and the precise use case.


Title: Re: PoW Algorithms
Post by: NeuroticFish on May 16, 2019, 09:40:28 AM
Since the question is unclear, I'll go on another direction.

If you are interested in which coins' algorithms are PoW and how many mining PoW algorithms exist, you should look at pages like

https://en.bitcoinwiki.org/wiki/Mining_algorithms
http://cryptomining24.net/list-of-cryptocurrencies/
https://www.crocosource.com/coins/algo/

The last list seems more comprehensive, but it also contains PoS mining algorithms, so you'll have to check them and "keep" only the PoW ones.


Title: Re: PoW Algorithms
Post by: HeRetiK on May 16, 2019, 09:49:11 AM
Here's a list of cryptographic hashes that are currently employed by various PoW coins:

https://en.bitcoinwiki.org/wiki/Mining_algorithms

This list is far from complete and to be honest I'm not even sure how current it is, but it should serve as a good starting point.

In general any cryptographic hash function can serve as the basis for a PoW scheme, however not all may be equally suitable. Additionally some coins cycle through cryptographic hash functions (if my memory serves me right, may also have just been a concept) and some coins shift between cryptographic hash functions depending on their emission lifecycle (eg. Grin will be shifting from CuckARoo to CuckAToo [1]).

[1] https://github.com/mimblewimble/docs/wiki/how-to-mine-grin


Title: Re: PoW Algorithms
Post by: DooMAD on May 16, 2019, 05:24:07 PM
Additionally some coins cycle through cryptographic hash functions (if my memory serves me right, may also have just been a concept)

Your memory serves you well.  There was a coin with 6 different hash functions and I had the distinct impression it was mostly a gimmick, as cycling hash functions doesn't guarantee that it's more secure, because security is dependent on other factors too.  But since it sounded like the kind of gimmick others might buy into, I still went ahead and bought some.  Naturally, it tanked and I invested poorly.   :D

As far as I know, it's still traded.  And, chances are, it's likely they're not the only coin doing stuff like that now.  So yep, the on-topic part of the story is that it's definitely possible to cycle hash functions.


Title: Re: PoW Algorithms
Post by: bob123 on May 17, 2019, 07:37:29 AM
Additionally some coins cycle through cryptographic hash functions (if my memory serves me right, may also have just been a concept)

Your memory serves you well.  There was a coin with 6 different hash functions and I had the distinct impression it was mostly a gimmick, as cycling hash functions doesn't guarantee that it's more secure, because security is dependent on other factors too.


IIRC, Verge was using 11 different algorithms which it cycled through.


Fun Fact: This actually was the reason attacker could perform multiple 51%+ attacks on it.

Instead of needing to gain more than 50% of the total hashrate, the attacker got 50%+ hashrate of 2 of those algorithms (the ones with the least miners) and manipulated the blocks that the 'next chosen algorithm' was the other one where they controlled the majority of the hashrate.
In addition to that, i believe, they found another flaw which allowed them to create a block each few seconds (instead of 1 per 1-2 minutes, don't remember exactly what their average block time was).

This combined was like the ultimate MCA which could happen to a crypto currency.

And i believe they didn't even needed the hardware for that, but simply rented the necessary hashrate (i am relatively, but not absolute, sure about that).


So, instead of having a coin which is more secure, they weakened the security by cycling through multiple hashing algorithms.
Their innovative approach to a ASIC-resistant and more secure coin, led them to be a laughingstock for the whole crypto community (without even mentioning that their so-called 'privacy' was basically non-existent).


Title: Re: PoW Algorithms
Post by: PixL on May 17, 2019, 03:29:44 PM
Well, Thank you all for your answers ! I got what i wanted in thoses links.
Thank you very much !
PixL