Scrypt proof of work - Revision history

Luke-jr: /* References */ Remove scamcoin promotion

2019-04-24T00:19:15Z

References: Remove scamcoin promotion

← Older revision		Revision as of 00:19, 24 April 2019
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	== References ==		== References ==
	<references/>		<references/>

	* [https://www.weusecoins.com/what-is-litecoin/ What is Litecoin?]
	* [https://www.bitcoinmining.com/what-is-litecoin-mining/ What is Litecoin Mining?]

Sunnankar: /* References */ References

2015-06-17T03:41:52Z

References: References

← Older revision		Revision as of 03:41, 17 June 2015
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	== References ==		== References ==
	<references/>		<references/>

			* [https://www.weusecoins.com/what-is-litecoin/ What is Litecoin?]
			* [https://www.bitcoinmining.com/what-is-litecoin-mining/ What is Litecoin Mining?]

Tromp: make distinction between hashcash pow and underlying hash function

2015-04-29T14:45:31Z

make distinction between hashcash pow and underlying hash function

← Older revision		Revision as of 14:45, 29 April 2015
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	'''Scrypt proof of work''' ~~is an alternative mining scheme that adds~~ memory-intensive ~~algorithms~~ to reduce the efficiency of logic circuits~~. This~~ was claimed to make only CPU mining remain profitable, even with the advent of GPU mining, and completely failed in that goal.		'''Scrypt proof of work''' denotes the [[Hashcash]] proof of work using scrypt as underlying hash function.
			By using a memory-intensive hash function designed to reduce the efficiency of logic circuits, this was claimed to make only CPU mining remain profitable, even with the advent of GPU mining, and completely failed in that goal.

	It has been less widely used and analyzed than the SHA2 hashing algorithm used in Bitcoin, so there is some concern about possible weaknesses in its cryptographic scheme being discovered in the future.		It has been less widely used and analyzed than the SHA2 hashing algorithm used in Bitcoin, so there is some concern about possible weaknesses in its cryptographic scheme being discovered in the future.

Luke-jr: Remove rewriting of historical claims and altcoin discussion, fix scrypt case (it is lowercase), and fix "some attempt" in erroneous "refutation"

2015-01-11T12:54:48Z

Remove rewriting of historical claims and altcoin discussion, fix scrypt case (it is lowercase), and fix "some attempt" in erroneous "refutation"

← Older revision		Revision as of 12:54, 11 January 2015
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	'''Scrypt proof of work''' is an alternative mining scheme that adds memory-intensive algorithms to reduce the efficiency of logic circuits. This was ~~a relatively successful attempt~~ to make CPU ~~and GPU~~ mining remain profitable, even with the advent of ~~FPGAs~~ and ~~ASICs for SHA mining~~.		'''Scrypt proof of work''' is an alternative mining scheme that adds memory-intensive algorithms to reduce the efficiency of logic circuits. This was claimed to make only CPU mining remain profitable, even with the advent of GPU mining, and completely failed in that goal.

			It has been less widely used and analyzed than the SHA2 hashing algorithm used in Bitcoin, so there is some concern about possible weaknesses in its cryptographic scheme being discovered in the future.

	== History ==		== History ==
	Originally introduced as part of the [[altcoin]] '''Tenebrix''' (TBX) by ArtForz and Lolcust, it was claimed to be resistant to GPU, FPGA, and ASIC implementation~~.<ref>[https://bitcointalk.org/?topic=45667 BitcoinTalk discussion thread for the "Tenebrix" altcoin]</ref> Tenebrix was heavily premined, so '''Fairbrix''' (FBX) was later launched as an alternative~~.		Originally introduced as part of the [[altcoin]] '''Tenebrix''' (TBX) by ArtForz and Lolcust, it was claimed to be resistant to GPU, FPGA, and ASIC implementation.

	=== Specialized hardware ===		=== Specialized hardware ===
	Around mid-2012, GPU-based ~~Scrypt~~ mining began to become widespread, and by late 2013 ~~Scrypt~~ ASICs had began shipping. As ~~Scrypt~~ is ~~no longer~~ GPU-resistant, FPGA-resistant or ASIC-resistant, it ~~is left with little use other than speculative altcoins~~.		Around mid-2012, GPU-based scrypt mining began to become widespread, and by late 2013 scrypt ASICs had began shipping. As scrypt is not GPU-resistant, FPGA-resistant nor ASIC-resistant, it has failed to meet its stated goals entirely.

	== Problems ==		== Problems ==
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	"51% attacks" become more difficult to launch and maintain as the hash rate of the network grows.		"51% attacks" become more difficult to launch and maintain as the hash rate of the network grows.
	However, this argument posits that since ~~Scrypt~~ is designed to be inefficient on all common computer components (both CPUs and GPUs), a malicious entity need only produce a small batch of specialized/custom hardware to overtake all the commodity mining systems combined.		However, this argument posits that since scrypt is designed to be inefficient on all common computer components (both CPUs and GPUs), a malicious entity need only produce a small batch of specialized/custom hardware to overtake all the commodity mining systems combined.

	=== Memory bandwidth refutation ===		=== Memory bandwidth refutation ===
	~~This issue is commonly refuted~~ by arguing that ~~Scrypt~~ is not designed to be inefficient, but is instead designed to be highly dependent on memory bandwidth.		Some attempt to refute this by arguing that scrypt is not designed to be inefficient, but is instead designed to be highly dependent on memory bandwidth.
	Since the high-speed cache RAM on modern processors already takes up most of the die space, no sizeable improvement could then be made by creating custom chips.		Since the high-speed cache RAM on modern processors already takes up most of the die space, no sizeable improvement could then be made by creating custom chips.
	If we accept this argument we then estimate the cost of attack utilizing GPUs that are available today.		If we accept this argument we then estimate the cost of attack utilizing GPUs that are available today.

Taras at 05:04, 10 January 2015

2015-01-10T05:04:31Z

← Older revision		Revision as of 05:04, 10 January 2015
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	Scrypt adds memory-intensive algorithms to reduce the efficiency of logic circuits.		'''Scrypt proof of work''' is an alternative mining scheme that adds memory-intensive algorithms to reduce the efficiency of logic circuits. This was a relatively successful attempt to make CPU and GPU mining remain profitable, even with the advent of FPGAs and ASICs for SHA mining.
	~~It has been less widely used~~ and ~~analyzed than the SHA2 hashing algorithm used in Bitcoin~~, ~~so there is some concern about possible weaknesses in its cryptographic scheme being discovered in~~ the ~~future~~.

	== History ==		== History ==
	Originally introduced as part of the altcoin "Tenebrix" by ArtForz and Lolcust, it was claimed to be resistant to GPU, FPGA, and ASIC implementation<ref>[https://bitcointalk.org/?topic=45667 BitcoinTalk discussion thread for the "Tenebrix" altcoin]</ref>.		Originally introduced as part of the [[altcoin]] '''Tenebrix''' (TBX) by ArtForz and Lolcust, it was claimed to be resistant to GPU, FPGA, and ASIC implementation.<ref>[https://bitcointalk.org/?topic=45667 BitcoinTalk discussion thread for the "Tenebrix" altcoin]</ref> Tenebrix was heavily premined, so '''Fairbrix''' (FBX) was later launched as an alternative.
	Around mid-2012, GPU-based mining began to become widespread ~~anyway~~, and in late 2013 ASICs began shipping.
			=== Specialized hardware ===
			Around mid-2012, GPU-based Scrypt mining began to become widespread, and by late 2013 Scrypt ASICs had began shipping. As Scrypt is no longer GPU-resistant, FPGA-resistant or ASIC-resistant, it is left with little use other than speculative altcoins.

	== Problems ==		== Problems ==
Line 11:		Line 12:

	"51% attacks" become more difficult to launch and maintain as the hash rate of the network grows.		"51% attacks" become more difficult to launch and maintain as the hash rate of the network grows.
	However, this argument posits that since ~~scrypt~~ is designed to be inefficient on all common computer components (both CPUs and GPUs), a malicious entity need only produce a small batch of specialized/custom hardware to overtake all the commodity mining systems combined.		However, this argument posits that since Scrypt is designed to be inefficient on all common computer components (both CPUs and GPUs), a malicious entity need only produce a small batch of specialized/custom hardware to overtake all the commodity mining systems combined.

	==== Memory bandwidth refutation ====		=== Memory bandwidth refutation ===
	~~Some attempt to refute this~~ by arguing that ~~scrypt~~ is not designed to be inefficient, but is instead designed to be highly dependent on memory bandwidth.		This issue is commonly refuted by arguing that Scrypt is not designed to be inefficient, but is instead designed to be highly dependent on memory bandwidth.
	Since the high-speed cache RAM on modern processors already takes up most of the die space, no sizeable improvement could then be made by creating custom chips.		Since the high-speed cache RAM on modern processors already takes up most of the die space, no sizeable improvement could then be made by creating custom chips.
	If we accept this argument we then estimate the cost of attack utilizing GPUs that are available today.		If we accept this argument we then estimate the cost of attack utilizing GPUs that are available today.

Luke-jr at 03:26, 3 April 2014

2014-04-03T03:26:21Z

← Older revision		Revision as of 03:26, 3 April 2014
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	== Problems ==		== Problems ==

	=== Vulnerability to mining monopoly ====		=== Vulnerability to mining monopoly ===

	"51% attacks" become more difficult to launch and maintain as the hash rate of the network grows.		"51% attacks" become more difficult to launch and maintain as the hash rate of the network grows.

Luke-jr: Initial page

2014-04-03T03:26:04Z

Initial page

New page

Scrypt adds memory-intensive algorithms to reduce the efficiency of logic circuits.
It has been less widely used and analyzed than the SHA2 hashing algorithm used in Bitcoin, so there is some concern about possible weaknesses in its cryptographic scheme being discovered in the future.

== History ==
Originally introduced as part of the altcoin "Tenebrix" by ArtForz and Lolcust, it was claimed to be resistant to GPU, FPGA, and ASIC implementation<ref>[https://bitcointalk.org/?topic=45667 BitcoinTalk discussion thread for the "Tenebrix" altcoin]</ref>.
Around mid-2012, GPU-based mining began to become widespread anyway, and in late 2013 ASICs began shipping.

== Problems ==

=== Vulnerability to mining monopoly ====

"51% attacks" become more difficult to launch and maintain as the hash rate of the network grows.
However, this argument posits that since scrypt is designed to be inefficient on all common computer components (both CPUs and GPUs), a malicious entity need only produce a small batch of specialized/custom hardware to overtake all the commodity mining systems combined.

==== Memory bandwidth refutation ====
Some attempt to refute this by arguing that scrypt is not designed to be inefficient, but is instead designed to be highly dependent on memory bandwidth.
Since the high-speed cache RAM on modern processors already takes up most of the die space, no sizeable improvement could then be made by creating custom chips.
If we accept this argument we then estimate the cost of attack utilizing GPUs that are available today.

To do so we start with an estimated cost of hardware at $400 per megahash per second and a reasonable network hashrate of 30 gigahashes per second.
The total amount of equipment necessary to match and takeover this network via 51% attack would then be an estimated $12M USD (or about 45,000 AMD HD 7950s).

== Variations ==

In mid-2013, a user nicknamed pocopoco introduced an altcoin ("YACoin") using scrypt with an adaptive "N-factor"<ref>[https://bitcointalk.org/?topic=196196 BitcoinTalk discussion thread for the "YACoin" altcoin]</ref>.

== References ==
<references/>