Bitcoin Wiki:Proof of work change hard fork - Revision history

JW at 17:31, 10 March 2018

2018-03-10T17:31:51Z

← Older revision		Revision as of 17:31, 10 March 2018
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			= Effects of a long anticipated PoW change =
			If the PoW change takes place after enough notice
			to miners and specialized hardware makers
			are able to switch without causing an accelerating
			the obsolescence of hardware.

	= Effects of a single unexpected PoW change =		= Effects of a single unexpected PoW change =

JW at 23:55, 9 March 2018

2018-03-09T23:55:56Z

← Older revision		Revision as of 23:55, 9 March 2018
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	~~== Proof of work change hard fork ==~~

	Changing the proof of work algorithm has been planned as a solution to ASIC mining centralization since as early as 2012 when Butterfly Labs first announced their intention to produce the first mining ASICs.

	~~'''JW:''' This history is not relevant to the discussion and should be removed. It also implies that it was agreed upon, by saying it was "planned." This is not true.~~

	'''LD:''' It is relevant, because it testifies to the fact that there is no excuse to be ignorant of the possibility of PoW change. It is not sudden or unexpected. Every ASIC miner on Bitcoin who has done basic due diligence is aware that the PoW algorithm may change, and specifically that it will probably change under these current circumstances.

	~~It is expected that by changing the PoW, the mining economy will be given a "restart" back to its original decentralized state.~~

	'''JW:''' While it would be "decentralized" until new speciality hardware is developed, it would be vulnerable to attack using specialized hardware. The goal isn't decentralization, but security. In this case that requires commoditization of cutting edge hardware. This approach is similar to creating a "gun free zone" instead of making gun ownership common. In the end only the bad guys will have ASICs.

	'''LD:''' There is no reason to expect speciality hardware will re-centralise. Incentives will have been made clear to deter that. And if not sufficiently so with one change, we can always change again and again until the message is understood. There is ZERO security from centralised mining. There is no "gun free zone" because ASICs are encouraged.

	~~And the current centralized miner (Bitmain) will incur significant enough financial loss to deter future centralization of the new algorithm.~~

	'''JW:''' Well it will certainly slow additional ASIC hardware manufacturers from atempting to build ASICs. But it won't prevent it. To do that we would need to change the PoW every time ASICs were known. The incentive would be to build ASICs and keep them secret. And well funded attackers would be able to invest in the best possible ASICs in order to attack a network that is not defended by the best possible ASICs. Bad in every way.

	~~'''LD:''' ASICs are not the same thing as centralisation, and it is not rational to claim their production would be deterred by a PoW change.~~

	~~=== Purpose of proof of work recap ===~~

	~~The purpose of proof of work is to ensure that the next block is randomly determined from a large pool of entities, without any centralised authority nominating such entities.~~

	~~=== Problems solved through a PoW change ===~~

	* The goal is to restore mining decentralisation.

	~~'''JW:''' This would be achieved only until someone, maybe a malicious actor, invested in ASICs.~~

	~~'''LD:''' With a simple algorithm, anyone can produce ASICs, and there would likely be multiple manufacturers. Bitmain only gained an inherent advantage over SHA2 by patenting the AsicBoost exploit.~~

	* By changing the PoW, Bitmain would suffer financial loss.

	'''JW:''' As would everyone that invested in ASIC manufacturing including competitors of Bitman. In fact the newest entrants would be hurt the worst since they have likely invested the most in ASICs that have not been recouped through sales.

	~~'''LD:''' No, see below. (Regardless, nobody was ever guaranteed a profit or break-even, and this risk was known long before anyone mining with ASICs invested in them; they chose to accept that risk.)~~

	* Any competent and benevolent manufacturing competitors to Bitmain would not suffer financial loss.

	~~'''JW:''' A PoW change doesn't discriminate. It harms everyone that has invested in SHA256 miners in proportion to their investment.~~

	~~'''LD:''' Competent ASIC manufacturers will design their chips with one or more backup algorithms (likely SHA2-related). This enables discrimination in PoW change scenarios.~~

	* Small miners would be able to mine the new algorithm using different hardware, likely at a higher network percentage than with Bitmain-issued hardware.

	'''JW:''' Miner centralization is a secondary issue with a PoW change. But miners that have recently entered the competition would be harmed more because they have a higher investment in hardware that has not earned a break even point through mining. Older miners, especially those with equipment nearer end of life, would be effected the least.

	'''LD:''' Mining centralisation defeats the entire purpose of PoW. It can never be secondary. But to the main point: these miners would still make a larger profit if the PoW algorithm was changed, than if it was not.




	~~=Section that follows is for a more detailed discussion=~~

	= Effects of a single unexpected PoW change =		= Effects of a single unexpected PoW change =

JW at 23:49, 9 March 2018

2018-03-09T23:49:10Z

Show changes

Luke-jr at 03:13, 8 March 2018

2018-03-08T03:13:45Z

Luke-jr: /* Problems solved through a PoW change */

2018-03-08T03:12:52Z

Problems solved through a PoW change

← Older revision		Revision as of 03:12, 8 March 2018
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	Changing the proof of work algorithm has been planned as a solution to ASIC mining centralization since as early as 2012 when Butterfly Labs first announced their intention to produce the first mining ASICs.		Changing the proof of work algorithm has been planned as a solution to ASIC mining centralization since as early as 2012 when Butterfly Labs first announced their intention to produce the first mining ASICs.
	~~Comment from JW: This history is not relevant to the discussion and should be removed. It also implies that it was agreed upon, by saying it was "planned." This is not true.~~

			'''JW:''' This history is not relevant to the discussion and should be removed. It also implies that it was agreed upon, by saying it was "planned." This is not true.

			LD: It is relevant, because it testifies to the fact that there is no excuse to be ignorant of the possibility of PoW change. It is not sudden or unexpected. Every ASIC miner on Bitcoin who has done basic due diligence is aware that the PoW algorithm may change, and specifically that it will probably change under these current circumstances.

	It is expected that by changing the PoW, the mining economy will be given a "restart" back to its original decentralized state.		It is expected that by changing the PoW, the mining economy will be given a "restart" back to its original decentralized state.
	~~Comment from~~ JW: While it would be "decentralized" until new speciality hardware is developed, it would be vulnerable to attack using specialized hardware. The goal isn't decentralization, but security. In this case that requires commoditization of cutting edge hardware. This approach is similar to creating a "gun free zone" instead of making gun ownership common. In the end only the bad guys will have ASICs.
			JW: While it would be "decentralized" until new speciality hardware is developed, it would be vulnerable to attack using specialized hardware. The goal isn't decentralization, but security. In this case that requires commoditization of cutting edge hardware. This approach is similar to creating a "gun free zone" instead of making gun ownership common. In the end only the bad guys will have ASICs.

			LD: There is no reason to expect speciality hardware will re-centralise. Incentives will have been made clear to deter that. And if not sufficiently so with one change, we can always change again and again until the message is understood. There is ZERO security from centralised mining. There is no "gun free zone" because ASICs are encouraged.

	And the current centralized miner (Bitmain) will incur significant enough financial loss to deter future centralization of the new algorithm.		And the current centralized miner (Bitmain) will incur significant enough financial loss to deter future centralization of the new algorithm.
	~~Comment from~~ JW: Well it will certainly slow additional ASIC hardware manufacturers from atempting to build ASICs. But it won't prevent it. To do that we would need to change the PoW every time ASICs were known. The incentive would be to build ASICs and keep them secret. And well funded attackers would be able to invest in the best possible ASICs in order to attack a network that is not defended by the best possible ASICs. Bad in every way.
			JW: Well it will certainly slow additional ASIC hardware manufacturers from atempting to build ASICs. But it won't prevent it. To do that we would need to change the PoW every time ASICs were known. The incentive would be to build ASICs and keep them secret. And well funded attackers would be able to invest in the best possible ASICs in order to attack a network that is not defended by the best possible ASICs. Bad in every way.

			LD: ASICs are not the same thing as centralisation, and it is not rational to claim their production would be deterred by a PoW change.

	=== Purpose of proof of work recap ===		=== Purpose of proof of work recap ===
Line 18:		Line 26:

	* The goal is to restore mining decentralisation.		* The goal is to restore mining decentralisation.

	JW: This would be achieved only until someone, maybe a malicious actor, invested in ASICs.		JW: This would be achieved only until someone, maybe a malicious actor, invested in ASICs.

			LD: With a simple algorithm, anyone can produce ASICs, and there would likely be multiple manufacturers. Bitmain only gained an inherent advantage over SHA2 by patenting the AsicBoost exploit.

	* By changing the PoW, Bitmain would suffer financial loss.		* By changing the PoW, Bitmain would suffer financial loss.

	JW: As would everyone that invested in ASIC manufacturing including competitors of Bitman. In fact the newest entrants would be hurt the worst since they have likely invested the most in ASICs that have not been recouped through sales.		JW: As would everyone that invested in ASIC manufacturing including competitors of Bitman. In fact the newest entrants would be hurt the worst since they have likely invested the most in ASICs that have not been recouped through sales.

			LD: No, see below. (Regardless, nobody was ever guaranteed a profit or break-even, and this risk was known long before anyone mining with ASICs invested in them; they chose to accept that risk.)

	* Any competent and benevolent manufacturing competitors to Bitmain would not suffer financial loss.		* Any competent and benevolent manufacturing competitors to Bitmain would not suffer financial loss.

	JW: A PoW change doesn't discriminate. It harms everyone that has invested in SHA256 miners in proportion to their investment.		JW: A PoW change doesn't discriminate. It harms everyone that has invested in SHA256 miners in proportion to their investment.

			LD: Competent ASIC manufacturers will design their chips with one or more backup algorithms (likely SHA2-related). This enables discrimination in PoW change scenarios.

	* Small miners would be able to mine the new algorithm using different hardware, likely at a higher network percentage than with Bitmain-issued hardware.		* Small miners would be able to mine the new algorithm using different hardware, likely at a higher network percentage than with Bitmain-issued hardware.

	JW: Miner centralization is a secondary issue with a PoW change. But miners that have recently entered the competition would be harmed more because they have a higher investment in hardware that has not earned a break even point through mining. Older miners, especially those with equipment nearer end of life, would be effected the least.		JW: Miner centralization is a secondary issue with a PoW change. But miners that have recently entered the competition would be harmed more because they have a higher investment in hardware that has not earned a break even point through mining. Older miners, especially those with equipment nearer end of life, would be effected the least.

			LD: Mining centralisation defeats the entire purpose of PoW. It can never be secondary. But to the main point: these miners would still make a larger profit if the PoW algorithm was changed, than if it was not.

	===New layout draft to capture both positions===		===New layout draft to capture both positions===

JW at 03:05, 8 March 2018

2018-03-08T03:05:12Z

← Older revision		Revision as of 03:05, 8 March 2018
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	=====On ASIC makers in early stages of development=====		=====On ASIC makers in early stages of development=====
	=====On ASIC makers with products near end of life=====		=====On ASIC makers with products near end of life=====
	=====On Miners with newer hardware=====		=====On Miners with newer specialized hardware=====
	=====On Miners with older hardware====		=====On Miners with older specialized hardware=====
	====Effects of an ongoing PoW changes ~~to prevent~~ ASIC makers====		====Effects of an expectation of ongoing PoW changes====
			=====On ASIC makers in early stages of development=====
			=====On ASIC makers with products near end of life=====
			=====On Miners with newer specialized hardware=====
			=====On Miners with older specialized hardware=====

JW at 03:02, 8 March 2018

2018-03-08T03:02:15Z

← Older revision		Revision as of 03:02, 8 March 2018
Line 25:		Line 25:
	* Small miners would be able to mine the new algorithm using different hardware, likely at a higher network percentage than with Bitmain-issued hardware.		* Small miners would be able to mine the new algorithm using different hardware, likely at a higher network percentage than with Bitmain-issued hardware.
	JW: Miner centralization is a secondary issue with a PoW change. But miners that have recently entered the competition would be harmed more because they have a higher investment in hardware that has not earned a break even point through mining. Older miners, especially those with equipment nearer end of life, would be effected the least.		JW: Miner centralization is a secondary issue with a PoW change. But miners that have recently entered the competition would be harmed more because they have a higher investment in hardware that has not earned a break even point through mining. Older miners, especially those with equipment nearer end of life, would be effected the least.



			===New layout draft to capture both positions===


			====Effects of a single unexpected PoW change====
			=====On ASIC makers in early stages of development=====
			=====On ASIC makers with products near end of life=====
			=====On Miners with newer hardware=====
			=====On Miners with older hardware====
			====Effects of an ongoing PoW changes to prevent ASIC makers====

JW: /* Proof of work change hard fork */

2018-03-08T02:51:07Z

Proof of work change hard fork

← Older revision		Revision as of 02:51, 8 March 2018
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	== Proof of work change hard fork ==		== Proof of work change hard fork ==

	Changing the proof of work algorithm has been planned as a solution to ASIC mining centralization since as early as 2012 when Butterfly Labs first announced their intention to produce the first mining ASICs.		Changing the proof of work algorithm has been planned as a solution to ASIC mining centralization since as early as 2012 when Butterfly Labs first announced their intention to produce the first mining ASICs.
	It is expected that by changing the PoW, the mining economy will be given a "restart" back to its original ~~decentralised~~ state, ~~and~~ the current ~~centralised~~ miner (Bitmain) will significant enough financial loss to deter future ~~centralisation~~ of the new algorithm.		Comment from JW: This history is not relevant to the discussion and should be removed. It also implies that it was agreed upon, by saying it was "planned." This is not true.


			It is expected that by changing the PoW, the mining economy will be given a "restart" back to its original decentralized state.
			Comment from JW: While it would be "decentralized" until new speciality hardware is developed, it would be vulnerable to attack using specialized hardware. The goal isn't decentralization, but security. In this case that requires commoditization of cutting edge hardware. This approach is similar to creating a "gun free zone" instead of making gun ownership common. In the end only the bad guys will have ASICs.

			And the current centralized miner (Bitmain) will incur significant enough financial loss to deter future centralization of the new algorithm.
			Comment from JW: Well it will certainly slow additional ASIC hardware manufacturers from atempting to build ASICs. But it won't prevent it. To do that we would need to change the PoW every time ASICs were known. The incentive would be to build ASICs and keep them secret. And well funded attackers would be able to invest in the best possible ASICs in order to attack a network that is not defended by the best possible ASICs. Bad in every way.

	=== Purpose of proof of work recap ===		=== Purpose of proof of work recap ===
Line 11:		Line 18:

	* The goal is to restore mining decentralisation.		* The goal is to restore mining decentralisation.
			JW: This would be achieved only until someone, maybe a malicious actor, invested in ASICs.
	* By changing the PoW, Bitmain would suffer financial loss.		* By changing the PoW, Bitmain would suffer financial loss.
			JW: As would everyone that invested in ASIC manufacturing including competitors of Bitman. In fact the newest entrants would be hurt the worst since they have likely invested the most in ASICs that have not been recouped through sales.
	* Any competent and benevolent manufacturing competitors to Bitmain would not suffer financial loss.		* Any competent and benevolent manufacturing competitors to Bitmain would not suffer financial loss.
			JW: A PoW change doesn't discriminate. It harms everyone that has invested in SHA256 miners in proportion to their investment.
	* Small miners would be able to mine the new algorithm using different hardware, likely at a higher network percentage than with Bitmain-issued hardware.		* Small miners would be able to mine the new algorithm using different hardware, likely at a higher network percentage than with Bitmain-issued hardware.
			JW: Miner centralization is a secondary issue with a PoW change. But miners that have recently entered the competition would be harmed more because they have a higher investment in hardware that has not earned a break even point through mining. Older miners, especially those with equipment nearer end of life, would be effected the least.

Luke-jr: Replace FUD with facts

2018-03-08T01:31:32Z

Replace FUD with facts

← Older revision		Revision as of 01:31, 8 March 2018
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	== Proof of work change hard fork ==		== Proof of work change hard fork ==

	~~Unexpectedly changing~~ the proof of work algorithm has been ~~suggested~~ as a solution to ASIC ~~manufacturing~~ centralization ~~(a lack of progress towards~~ mining ~~hardware commoditization)~~. It is ~~suggested~~ that by changing the PoW ~~existing hardware manufacturers will suffer great financial loss and this will "make room" for additional competition. In actuality, likely profits~~, ~~attracts additional competition. By increasing~~ the ~~risk involved in making~~ mining ~~hardware, by showing that their R&D investments could~~ be ~~completely lost by~~ a ~~PoW change~~, ~~competitors~~ will ~~be more discouraged~~ to ~~make~~ the ~~required investment. This document is an attempt to make these simple, and universal, economic truths clear in this particular application~~.		Changing the proof of work algorithm has been planned as a solution to ASIC mining centralization since as early as 2012 when Butterfly Labs first announced their intention to produce the first mining ASICs.
			It is expected that by changing the PoW, the mining economy will be given a "restart" back to its original decentralised state, and the current centralised miner (Bitmain) will significant enough financial loss to deter future centralisation of the new algorithm.

	=== Purpose of proof of work recap ===		=== Purpose of proof of work recap ===

	* The purpose of proof of work is to ~~burn electricity in a way that is as efficient as humanly possible and easily verified.~~		The purpose of proof of work is to ensure that the next block is randomly determined from a large pool of entities, without any centralised authority nominating such entities.
	* This shows how much cost was involved in presenting a set of transactions as valid. If that cost is high enough we can trust that the ~~network was in agreement and that the cost of attempting an invalid transaction was also very high.~~
	* Because “blocks of transactions are chained together we can be more confident in older blocks that have had additional investment in electricity burn on top of them.


	~~=== Problems we want to solve through an unexpected PoW change ===~~

	* The goal is ~~to accelerate mining hardware commoditization.~~
	* By changing the PoW all existing investors in mining hardware would suffer financial loss.
	* The more recent the investment the greater the loss because a recent investment would not have produced any income yet.
	* For example if someone invested 10B in a new chip design, but had not sold a ~~single chip, that entire investment would be lost with a PoW change.~~
	* If someone invested 10B in in a chip design a year ago and had already earned 10B on that design, they would be at a break even.

	~~=== Problems solved through an unexpected PoW change ===~~
	* Increase commoditization of ~~ASIC hardware.~~
	**Hard fail. Opposite effect - less competition is the obvious result.
	* To increase the decentralization of mining. More miners spread out in more geographic locations owned and controlled by more individuals.
	** Hard fail. With less commoditization of ASICs, ~~a greater ability for a bad actor to invest in ASICs and dominate the hash rate will not be decentralized.~~
	* If the PoW was changed every month we could get less centralization, but at the cost of being completely open to attack by anyone willing to invest in the unprofitable business of specialty hardware.

	=== ~~Long term counterproductive effects on ASIC manufacturing~~ ===		=== Problems solved through a PoW change ===
	* Companies that were about to invest in ASIC manufacturing would realize they would have suffered a greater loss than any other potential investment had they moved sooner.
	** 100% loss on a chip design is an unusually bad outcome.
	* Anyone considering entrance into ASIC manufacturing would need to expect much higher profits than before to compensate for the risk that this would happen again.
	* Anyone considering entrance into ASIC manufacturing would need to be more capitalized in order to be able to weather another proof of work change without being financially destroyed.
	* Competition among ASIC manufacturing would be reduced - Mining hardware creation would be more centralized
	* The rapid march towards commoditization, created by competition, would be slowed.
	* Bitcoin would be more vulnerable to an attacker investing into ASIC hardware for the purpose of attacking the network.

	~~=== Short term counterproductive effects on bitcoin~~ mining ~~===~~		* The goal is to restore mining decentralisation.
	* ~~The amount of electricity spent at~~ the ~~height of human efficiency~~ would ~~drop to 0%. This is the hash rate that matters~~.		* By changing the PoW, Bitmain would suffer financial loss.
	* ~~All existing bitcoin miners would be poorer in proportion~~ to ~~the newness of their equipment. Miners running equipment near end of life~~ would ~~be affected the least~~.		* Any competent and benevolent manufacturing competitors to Bitmain would not suffer financial loss.
	* ~~Supporters of bitcoin~~ would ~~need~~ to mine using ~~inefficient equipment.~~		* Small miners would be able to mine the new algorithm using different hardware, likely at a higher network percentage than with Bitmain-issued hardware.
	* An well funded attacker, ~~such as~~ a ~~corrupt government, could dominate the~~ network ~~by making an investment in ASICs that a private company would consider to risky (unprofitable)~~.

JW: JW moved page Your new page title here to Bitcoin Wiki:Proof of work change hard fork: fix title

2018-03-08T01:05:23Z

JW moved page Your new page title here to Bitcoin Wiki:Proof of work change hard fork: fix title

← Older revision	Revision as of 01:05, 8 March 2018
(No difference)

← Older revision		Revision as of 03:13, 8 March 2018
Line 5:		Line 5:
	'''JW:''' This history is not relevant to the discussion and should be removed. It also implies that it was agreed upon, by saying it was "planned." This is not true.		'''JW:''' This history is not relevant to the discussion and should be removed. It also implies that it was agreed upon, by saying it was "planned." This is not true.

	LD: It is relevant, because it testifies to the fact that there is no excuse to be ignorant of the possibility of PoW change. It is not sudden or unexpected. Every ASIC miner on Bitcoin who has done basic due diligence is aware that the PoW algorithm may change, and specifically that it will probably change under these current circumstances.		'''LD:''' It is relevant, because it testifies to the fact that there is no excuse to be ignorant of the possibility of PoW change. It is not sudden or unexpected. Every ASIC miner on Bitcoin who has done basic due diligence is aware that the PoW algorithm may change, and specifically that it will probably change under these current circumstances.

	It is expected that by changing the PoW, the mining economy will be given a "restart" back to its original decentralized state.		It is expected that by changing the PoW, the mining economy will be given a "restart" back to its original decentralized state.

	JW: While it would be "decentralized" until new speciality hardware is developed, it would be vulnerable to attack using specialized hardware. The goal isn't decentralization, but security. In this case that requires commoditization of cutting edge hardware. This approach is similar to creating a "gun free zone" instead of making gun ownership common. In the end only the bad guys will have ASICs.		'''JW:''' While it would be "decentralized" until new speciality hardware is developed, it would be vulnerable to attack using specialized hardware. The goal isn't decentralization, but security. In this case that requires commoditization of cutting edge hardware. This approach is similar to creating a "gun free zone" instead of making gun ownership common. In the end only the bad guys will have ASICs.

	LD: There is no reason to expect speciality hardware will re-centralise. Incentives will have been made clear to deter that. And if not sufficiently so with one change, we can always change again and again until the message is understood. There is ZERO security from centralised mining. There is no "gun free zone" because ASICs are encouraged.		'''LD:''' There is no reason to expect speciality hardware will re-centralise. Incentives will have been made clear to deter that. And if not sufficiently so with one change, we can always change again and again until the message is understood. There is ZERO security from centralised mining. There is no "gun free zone" because ASICs are encouraged.

	And the current centralized miner (Bitmain) will incur significant enough financial loss to deter future centralization of the new algorithm.		And the current centralized miner (Bitmain) will incur significant enough financial loss to deter future centralization of the new algorithm.

	JW: Well it will certainly slow additional ASIC hardware manufacturers from atempting to build ASICs. But it won't prevent it. To do that we would need to change the PoW every time ASICs were known. The incentive would be to build ASICs and keep them secret. And well funded attackers would be able to invest in the best possible ASICs in order to attack a network that is not defended by the best possible ASICs. Bad in every way.		'''JW:''' Well it will certainly slow additional ASIC hardware manufacturers from atempting to build ASICs. But it won't prevent it. To do that we would need to change the PoW every time ASICs were known. The incentive would be to build ASICs and keep them secret. And well funded attackers would be able to invest in the best possible ASICs in order to attack a network that is not defended by the best possible ASICs. Bad in every way.

	LD: ASICs are not the same thing as centralisation, and it is not rational to claim their production would be deterred by a PoW change.		'''LD:''' ASICs are not the same thing as centralisation, and it is not rational to claim their production would be deterred by a PoW change.

	=== Purpose of proof of work recap ===		=== Purpose of proof of work recap ===
Line 27:		Line 27:
	* The goal is to restore mining decentralisation.		* The goal is to restore mining decentralisation.

	JW: This would be achieved only until someone, maybe a malicious actor, invested in ASICs.		'''JW:''' This would be achieved only until someone, maybe a malicious actor, invested in ASICs.

	LD: With a simple algorithm, anyone can produce ASICs, and there would likely be multiple manufacturers. Bitmain only gained an inherent advantage over SHA2 by patenting the AsicBoost exploit.		'''LD:''' With a simple algorithm, anyone can produce ASICs, and there would likely be multiple manufacturers. Bitmain only gained an inherent advantage over SHA2 by patenting the AsicBoost exploit.

	* By changing the PoW, Bitmain would suffer financial loss.		* By changing the PoW, Bitmain would suffer financial loss.

	JW: As would everyone that invested in ASIC manufacturing including competitors of Bitman. In fact the newest entrants would be hurt the worst since they have likely invested the most in ASICs that have not been recouped through sales.		'''JW:''' As would everyone that invested in ASIC manufacturing including competitors of Bitman. In fact the newest entrants would be hurt the worst since they have likely invested the most in ASICs that have not been recouped through sales.

	LD: No, see below. (Regardless, nobody was ever guaranteed a profit or break-even, and this risk was known long before anyone mining with ASICs invested in them; they chose to accept that risk.)		'''LD:''' No, see below. (Regardless, nobody was ever guaranteed a profit or break-even, and this risk was known long before anyone mining with ASICs invested in them; they chose to accept that risk.)

	* Any competent and benevolent manufacturing competitors to Bitmain would not suffer financial loss.		* Any competent and benevolent manufacturing competitors to Bitmain would not suffer financial loss.

	JW: A PoW change doesn't discriminate. It harms everyone that has invested in SHA256 miners in proportion to their investment.		'''JW:''' A PoW change doesn't discriminate. It harms everyone that has invested in SHA256 miners in proportion to their investment.

	LD: Competent ASIC manufacturers will design their chips with one or more backup algorithms (likely SHA2-related). This enables discrimination in PoW change scenarios.		'''LD:''' Competent ASIC manufacturers will design their chips with one or more backup algorithms (likely SHA2-related). This enables discrimination in PoW change scenarios.

	* Small miners would be able to mine the new algorithm using different hardware, likely at a higher network percentage than with Bitmain-issued hardware.		* Small miners would be able to mine the new algorithm using different hardware, likely at a higher network percentage than with Bitmain-issued hardware.

	JW: Miner centralization is a secondary issue with a PoW change. But miners that have recently entered the competition would be harmed more because they have a higher investment in hardware that has not earned a break even point through mining. Older miners, especially those with equipment nearer end of life, would be effected the least.		'''JW:''' Miner centralization is a secondary issue with a PoW change. But miners that have recently entered the competition would be harmed more because they have a higher investment in hardware that has not earned a break even point through mining. Older miners, especially those with equipment nearer end of life, would be effected the least.

	LD: Mining centralisation defeats the entire purpose of PoW. It can never be secondary. But to the main point: these miners would still make a larger profit if the PoW algorithm was changed, than if it was not.		'''LD:''' Mining centralisation defeats the entire purpose of PoW. It can never be secondary. But to the main point: these miners would still make a larger profit if the PoW algorithm was changed, than if it was not.

	===New layout draft to capture both positions===		===New layout draft to capture both positions===