
Bitcoin has computed 2^83.9 hashes - mrb
https://plus.google.com/+MarcBevand/posts/1HN6Nnf7LBD/
======
kls
I will admit I am not up on block chain tech or the process it uses, but it
does seem like a lot of wasted resources to just compute hashes. It seems like
someone could make a system where real work units count as credit in an
issuing lottery. Kind of like SETI @ Home, medical or genome work where you
distribute a problem and then people get tickets for accomplishing some form
of work. Seems to me that this would be a better use of such vast computing
power and would help with discovery at the same time. Again it's not my area
of expertise so I don't understand the details or issues that would arise in
ordering the work units around distributed computation to solve large
problems. It would be nice if researchers had open and free access to such a
system.

~~~
golergka
These are not "wasted" resources; they create value, which is the trust for
the distributed currency system. These are hashes based on real history of
transactions, and their computations guarantee that these transactions have
been recorded by third party.

(At least, that's how it should work if I understand the theory behind bitcoin
correctly).

~~~
splintercell
Exactly. It's like claiming that HTTPS encryption is wasted resources, because
all you do is encrypt things at one end, only to decrypt at the other.

Bitcoin's computation does the job of securing the blockchain by forcing an
attacker to spend computation cycles to match up the computation done for
these hashes.

~~~
jbssm
HTTPS encryption doesn't get more difficult to compute as time goes by.

HTTPS is the means to an end, bitcoin is just wasting resources.

If the point was just to maintain the blockchain integrity there would be no
need to make its difficulty ever increasing.

~~~
cyphar
> HTTPS is the means to an end, bitcoin is just wasting resources.

Bitcoins is also a means to an end, you just don't seem to understand what the
end is.

> If the point was just to maintain the blockchain integrity there would be no
> need to make its difficulty ever increasing.

This is incorrect. The blockchain requires miners to establish an unbiased
ledger history. The difficulty parameter is tweaked so that the whole system
can be future proofed against an adversary creating a convincing blockchain
history (which was biased to double-spending or retracting a transaction).

~~~
jbssm
> This is incorrect. The blockchain requires miners to establish an unbiased
> ledger history. The difficulty parameter is tweaked so that the whole system
> can be future proofed against an adversary creating a convincing blockchain
> history (which was biased to double-spending or retracting a transaction).

What was the excuse in the early days of bitcoin then when the difficulty was
orders of magnitude lower?

Difficulty is ever increasing just because of the financial model bitcoin
tries to propagate. The author of bitcoin wanted to make it deflational and so
it had to be this way.

That part has nothing to do with the integrity of the blockchain and you are
mixing two concepts here: Blockchain, which was a great invention and bitcoin,
a financial experience (nothing against experiences from my part) which turned
out to be a waste of resources.

~~~
cyphar
> > This is incorrect. The blockchain requires miners to establish an unbiased
> ledger history. The difficulty parameter is tweaked so that the whole system
> can be future proofed against an adversary creating a convincing blockchain
> history (which was biased to double-spending or retracting a transaction).

> What was the excuse in the early days of bitcoin then when the difficulty
> was orders of magnitude lower?

... because there wasn't as much hashing power in the bitcoin network? Isn't
that obvious? The difficulty parameters are tweaked so that the proof of work
takes 10 minutes for the whole network. As the network gets bigger, you need
to make it harder to maintain a 10 minute proof of work.

> Difficulty is ever increasing just because of the financial model bitcoin
> tries to propagate. The author of bitcoin wanted to make it deflational and
> so it had to be this way.

Eh. You're full of shit. But that's your prerogative.

> That part has nothing to do with the integrity of the blockchain and you are
> mixing two concepts here: Blockchain, which was a great invention and
> bitcoin, a financial experience (nothing against experiences from my part)
> which turned out to be a waste of resources.

Integrity of the blockchain is maintained by cryptographic hashes. There are
other security properties (such as proof of work and thus non-malleability)
that are maintained by the difficulty parameter.

------
kushti
This is definitely the waste of resources. A lottery to choose a block
generator could be useful, e.g. PrimeCoin or
PermaCoin([http://cs.umd.edu/~amiller/permacoin.pdf](http://cs.umd.edu/~amiller/permacoin.pdf)).
We are working to launch Scorex([https://github.com/ScorexProject/Scorex-
Lagonaki](https://github.com/ScorexProject/Scorex-Lagonaki)) w. Permacoin
testnet in coming days.

~~~
ghayes
From the referenced document where OP says "No, this is not wasteful" [0]:

"Miners currently use approximately only 0.0012% .. [and] economic modelling
predicts miners will not account for more than 0.74% of the energy consumed by
the world".

Expending nearly 1% of all energy consumed by the world is an insanely large
figure. How much hubris does it take to call this "not wasteful" on its face?

[0] Miners currently use approximately only 0.0012%

~~~
mrb
The model I used to calculate 0.74% assumes Bitcoin's market cap is $1
trillion(!).

We can all agree that IF the market cap gets this large, it will mean Bitcoin
will have had a huge positive impact on society. Therefore it will have been
worth it to spend 0.74% of the world's energy.

Edit: I am puzzled by the downvotes. I would like to hear (and respond to)
counterpoints if what I am saying is incredibly silly.

~~~
kansface
> We can all agree that IF the market cap gets this large, it will mean
> Bitcoin will have had a huge positive impact on society.

What, why?! Even if that were the case, it doesn't follow that the good it
does outweighs using 1% of all energy.

~~~
mrb
I will explain.

Firstly, I think you are underestimating the societal impact that would have
led a cryptocurrency to be worth $1 trillion. It would mean it has succeeded
on a massive scale: foreign trade made more fluid thanks to Bitcoin's
disregard of political borders, hundreds of millions of people using it to
escape inflation/financial restrictions/etc (vs. today's few million users),
millions of merchants accepting it (vs. today's 130 000 merchants). All
Bitcoin would have to accomplish to justify using 0.X% of the world's energy
is to increase the world GDP by 0.X%.

Secondly, 0.74% is an upper bound. It assumes power costs of $0.01 per kWh
(read section 2 at
[http://blog.zorinaq.com/?e=82](http://blog.zorinaq.com/?e=82)) when actually
the average power cost worldwide is 10x higher ($0.10/kWh). Maybe it will be
0.3% of the total energy. Maybe 0.1%. How low is low enough that you would
consider it worthwhile?

~~~
PhilWright
There is no level of hash calculations that is acceptable.

It is crazy to have a currency that requires this dumb make-work of hashing
which results in CO2 emissions. We live in a world of dangerous climate change
and Bitcoin users want us to expel CO2 into the atmosphere with every currency
transaction. That is dumb and not sustainable.

~~~
mrb
I actually address this point in my post: _" Many/most miners use
hydroelectric power because competition compels them to use cheap renewable
energy instead of other polluting power sources such as coal power plants"_
examples:

BitFury:
[https://www.businesswire.com/news/home/20151211005837/en/Bit...](https://www.businesswire.com/news/home/20151211005837/en/BitFury-
Launch-Energy-Efficient-Immersion-Cooling-Data)

KnC: [http://thenodepole.com/2015/06/04/kncminer-to-build-
new-20mw...](http://thenodepole.com/2015/06/04/kncminer-to-build-new-20mw-
greenfield-datacenter-in-the-node-pole/)

Therefore your worry about CO₂ emissions is misplaced.

------
yuhong
Unrelated to hashes, but from [https://www.ietf.org/archive/id/draft-kaduk-
afs3-rxkad-k5-kd...](https://www.ietf.org/archive/id/draft-kaduk-
afs3-rxkad-k5-kdf-00.txt) :

"Although administrative access to the cell still uses single-DES for
encryption of network traffic, that single-DES key is time limited and may be
resistant to brute-force key recovery prior to its expiration."

This wasn't created until after CloudCracker can break DES, but to be honest
OpenAFS is not the only one either. DOCSIS I think do something similar too. I
wonder if anyone has created ASICs to break DES.

~~~
DanBC
See, for example, COPACOBANA which uses FPGAs to crack some crypto, including
DES. That was in 2008.

[http://www.copacobana.org/](http://www.copacobana.org/)

> COPACOBANA, the Cost-Optimized Parallel COde Breaker, is an FPGA-based
> machine which is optimized for running cryptanalytical algorithms.
> COPACOBANA is suitable for parallel computation problems which have low
> communication requirements. DES cracking is such a parallelizable problem:
> an exhaustive key search of the Data Encryption Standard (DES) takes no
> longer than a week on average with COPACOBANA. Other ciphers can be attacked
> too, and COPACOBANA can also be used for parallel computing problem outside
> cryptography.

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winter45
I'm not a math type, but it looks to me that mrb is saying that the number of
computed bitcoin hashes outnumber an estimated number of all of the grains of
sand on the world's beaches, and in the world's deserts, by a factor of 10^6th

[http://tinyurl.com/hf9aybm](http://tinyurl.com/hf9aybm)
[http://tinyurl.com/qc59ora](http://tinyurl.com/qc59ora)

------
Pharaoh2
Well this image proves that the bitcoin network is not only alive and well but
it is growing at an impressive rate and anyone saying that bitcoin is dying is
lying to you and possibly pushing his own agenda.

[http://bitcoin.sipa.be/speed-lin-ever.png](http://bitcoin.sipa.be/speed-lin-
ever.png)

------
tveita
That's about 2^58 hashes and 50.000.000 joules (14 kWh) per transaction when
operating at the theoretical peak of around 3 transactions per second.

------
orasis
How many watts and tons of CO2 is that?

~~~
mrb
_" the bottom line is that investing a hundred+ megawatt in a system that so
far created thousands of jobs is a valuable economic move, not a waste."_

Plus many other good arguments in
[http://blog.zorinaq.com/?e=82](http://blog.zorinaq.com/?e=82) please read it.

------
fapjacks
Bitcoin is not in a good spot.

~~~
kbenzle
What, why?

~~~
fapjacks
Please be sure to read the links posted in this post:
[https://medium.com/@octskyward/the-resolution-of-the-
bitcoin...](https://medium.com/@octskyward/the-resolution-of-the-bitcoin-
experiment-dabb30201f7#.yafcp4f31)

