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Date: Sun, 16 Sep 2018 16:20:05 -0700
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To: Damian Williamson <willtech@live.com.au>,
	Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>
Subject: Re: [bitcoin-dev] Selfish Mining Prevention
Precedence: list


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Hash rate cannot get =E2=80=9Cmore uneconomical=E2=80=9D. Mining will always=
 seek a return equal to the cost of capital, as does all production, and the=
 energy expended will always be fundamentally a function of the fee level an=
d energy price. Fee level is determined by variable demand for a fixed suppl=
y of confirmation.

When you say greed you are simply referring to economically-rational behavio=
r. It canny be eliminated, nor would that be a benefit.

WRT energy consumption, there is nothing that can be done to reduce it excep=
t for people to stop using Bitcoin or for energy to get more expensive.

e

> On Sep 15, 2018, at 15:45, Damian Williamson via bitcoin-dev <bitcoin-dev@=
lists.linuxfoundation.org> wrote:
>=20
> I see what you say, however, since the proposal as I have read it says "An=
d this will keep happening as long as hashrate keeps rising," - what actuall=
y happens in the case hashrate stagnates or falls?
>=20
> I would prefer to see (not only with your proposal) greater bias toward ha=
shrate being exponentially more uneconomical the more it rises to stifle gre=
ed. The current level of mining already greatly exceeds that necessary for t=
he stability of the network and far lower hashrates are completely acceptibl=
e provided the network is protected from large switch-ons, which I say is ac=
hievable.
>=20
> I do have other thoughts to approach greed that I have not yet made formal=
 on this list, much unrelated to your proposal, but, I see freedom of use of=
 Bitcoin needing to be censorship resistant but not necessarily mining provi=
ded it is protected enough or free or flexible enough to allow for, say, 50k=
 globally distributed standard mining hardware units to exist operating at a=
ny one time profitably. That said, I am PoW only and not PoS orientated.
> =20
> From: akaramaoun@gmail.com <akaramaoun@gmail.com> on behalf of Andrew <one=
lineproof@gmail.com>
> Sent: Sunday, 16 September 2018 2:01:19 AM
> To: Damian Williamson
> Cc: Bitcoin Protocol Discussion
> Subject: Re: [bitcoin-dev] Selfish Mining Prevention
> =20
> @Moral Agent: No problem. I did ask in the first post what the current
> plans are for selfish miner prevention. So if anyone has any other
> relevant ideas (not just for selfish mining but for making mining more
> decentralized and competetive), then please post it, but I just prefer
> to focus on my proposal more than others.
>=20
> @Damian: I think you are concerned that this will incentivize more
> global resource consumption and will be detrimental to our
> environment? Personally, I believe centralization of energy does more
> harm to the environment rather than total energy consumption. If
> Bitcoin helps "power" to become more decentralized, then I wouldn't be
> surprised if total (global) energy consumption actually decreases. The
> debt based economy is forcing us to continuously grow and use up more
> resources, and collectivism is turning individuals into
> super-organisms capable of doing much more harm to the environment
> than can be done by one or a just a few individuals working
> independently. In my proposal, I actually allow for changing
> environmental conditions by measuring only the peak hashrate of the
> past year, and not the full history of blocks.
>=20
> On Sat, Sep 15, 2018 at 5:29 AM, Damian Williamson <willtech@live.com.au> w=
rote:
> >>This "reserve" part of the fee will be paid to miners if the hashrate
> >> rises.
> >
> >
> > Anticipating ongoing hashrate rise shows that you have not yet thought a=
bout
> > moving outside of the current greed model, a model wherein mining will
> > consume all available resources within the colony's objective just to sp=
read
> > as far as possible with each new miner bringing diminishing individual
> > returns and shortening the life of Earth for no additional gain. Greed m=
odel
> > :=3D bacteria.
> >
> > ________________________________
> > From: bitcoin-dev-bounces@lists.linuxfoundation.org
> > <bitcoin-dev-bounces@lists.linuxfoundation.org> on behalf of Andrew via
> > bitcoin-dev <bitcoin-dev@lists.linuxfoundation.org>
> > Sent: Friday, 14 September 2018 9:19:37 AM
> > To: Bitcoin Dev
> > Subject: Re: [bitcoin-dev] Selfish Mining Prevention
> >
> > I discussed this more at bitcointalk:
> > https://bitcointalk.org/index.php?topic=3D4998410.0
> >
> > The attacks I'm interested in preventing are not only selfish mining
> > and collusion, but also more subtle attacks like block withholding,
> > and in general anything that aims to drive out the competition in
> > order to increase hashrate fraction. I also scrapped the idea of
> > changing the block subsidies, and I am only focuses on fees.
> >
> > You can read more about the motivation and details in the bitcointalk
> > thread, but my proposal in short would be to add the concept of
> > "reserve fees". When a user makes a transaction, for each txout
> > script, they can add parameters that specify the fraction of the total
> > fee that is held in "reserve" and the time it is held in "reserve"
> > (can set a limit of 2016 blocks). This "reserve" part of the fee will
> > be paid to miners if the hashrate rises. So if hashrate is currently h
> > and peak hashrate (from past year) is p, then for each period (1 day),
> > a new hashrate is calculated h1, and if h1 > h, then the fraction
> > (h1-h)/p from the reserve fees created in the past 2016 blocks will be
> > released to miners for that period (spread out over the 144 blocks in
> > that period). And this will keep happening as long as hashrate keeps
> > rising, until the "contract" expires, and the leftover part can be
> > used by the owner of the unspent output, but it can only be used for
> > paying fees, not as inputs for future transactions (to save on block
> > space).
> >
> > This should incentivize miners to not drive out the competition, since
> > if they do, there will be less of these reserve fees given to miners.
> > Yes in the end the miners will get all the fees, but with rising
> > hashrate they get an unconditional subsidy that does not require
> > transactions, thus more space for transactions with fees.
> >
> > I can make a formal BIP and pull request, but I need to know if there
> > is interest in this. Now fees don't play such a large part of the
> > block reward, but they will get more important, and this change
> > wouldn't force anything (would be voluntary by each user), just miners
> > have to agree to it with a soft fork (so they don't spend from the
> > anyone-can-spend outputs used for reserve fees). Resource requirements
> > for validation are quite small I believe.
> >
> > On Sat, Sep 1, 2018 at 12:11 AM, Andrew <onelineproof@gmail.com> wrote:
> >> As I understand, selfish mining is an attack where miners collude to
> >> mine at a lower hashrate then with all miners working independently.
> >> What are the current strategies used to prevent this and what are the
> >> future plans?
> >>
> >> One idea I have is to let the block reward get "modulated" according
> >> to peak hashrate. Say p is the peak hashrate for 365 periods (1 year)
> >> consisting of 144 blocks, h is the hashrate of the last 144 block (1
> >> day) period, and r is the base subsidy (12.5 BTC currently). You can
> >> then make the max block reward 0.5 r (1 + h/p). So if hashrate is at
> >> peak you get the full reward. Otherwise you get less, down to a min of
> >> 0.5 r.
> >>
> >> If miners were to collude to mine at a lower than peak hashrate, then
> >> they may be able to do it profitably for 144 blocks, but after that,
> >> the reward would get modulated and it wouldn't be so much in their
> >> interest to continue mining at the lower hashrate.
> >>
> >> What flaws are there with this? I know it could be controversial due
> >> to easier mining present for early miners, so maybe it would have to
> >> be done in combination with a new more dynamic difficulty adjustment
> >> algorithm. But I don't see how hashrate can continue rising
> >> indefinitely, so a solution should be made for selfish mining.
> >>
> >> Also when subsidies stop and a fee market is needed, I guess a portion
> >> of the fees can be withheld for later if hashrate is not at peak.
> >>
> >>
> >> --
> >> PGP: B6AC 822C 451D 6304 6A28  49E9 7DB7 011C D53B 5647
> >
> >
> >
> > --
> > PGP: B6AC 822C 451D 6304 6A28  49E9 7DB7 011C D53B 5647
> > _______________________________________________
> > bitcoin-dev mailing list
> > bitcoin-dev@lists.linuxfoundation.org
> > https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>=20
>=20
>=20
> --=20
> PGP: B6AC 822C 451D 6304 6A28  49E9 7DB7 011C D53B 5647
> _______________________________________________
> bitcoin-dev mailing list
> bitcoin-dev@lists.linuxfoundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev

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<html><head><meta http-equiv=3D"content-type" content=3D"text/html; charset=3D=
utf-8"></head><body dir=3D"auto"><div></div><div>Hash rate cannot get =E2=80=
=9Cmore uneconomical=E2=80=9D. Mining will always seek a return equal to the=
 cost of capital, as does all production, and the energy expended will alway=
s be fundamentally a function of the fee level and energy price. Fee level i=
s determined by variable demand for a fixed supply of confirmation.</div><di=
v><br></div><div>When you say greed you are simply referring to economically=
-rational behavior. It canny be eliminated, nor would that be a benefit.</di=
v><div><br></div><div>WRT energy consumption, there is nothing that can be d=
one to reduce it except for people to stop using Bitcoin or for energy to ge=
t more expensive.</div><div><br></div><div>e</div><div><br>On Sep 15, 2018, a=
t 15:45, Damian Williamson via bitcoin-dev &lt;<a href=3D"mailto:bitcoin-dev=
@lists.linuxfoundation.org">bitcoin-dev@lists.linuxfoundation.org</a>&gt; wr=
ote:<br><br></div><blockquote type=3D"cite"><div>

<meta http-equiv=3D"Content-Type" content=3D"text/html; charset=3Dus-ascii">=




<div id=3D"divtagdefaultwrapper" style=3D"font-size:12pt;color:#000000;font-=
family:Calibri,Helvetica,sans-serif;" dir=3D"ltr">
<p style=3D"margin-top:0;margin-bottom:0">I see what you say, however, since=
 the proposal as I have read it
<font size=3D"2"><span style=3D"font-size:11pt;">says "And this will keep ha=
ppening as long as hashrate keeps rising," - what actually happens in the ca=
se hashrate stagnates or falls?</span></font></p>
<p style=3D"margin-top:0;margin-bottom:0"><font size=3D"2"><span style=3D"fo=
nt-size:11pt;"><br>
</span></font></p>
<p style=3D"margin-top:0;margin-bottom:0"><font size=3D"2"><span style=3D"fo=
nt-size:11pt;">I would prefer to see (not only with your proposal) greater b=
ias toward hashrate being exponentially more uneconomical the more it rises t=
o stifle greed. The current level
 of mining already greatly exceeds that necessary for the stability of the n=
etwork and far lower hashrates are completely acceptible provided the networ=
k is protected from large switch-ons, which I say is achievable.<br>
</span></font></p>
<p style=3D"margin-top:0;margin-bottom:0"><font size=3D"2"><span style=3D"fo=
nt-size:11pt;"><br>
</span></font></p>
<p style=3D"margin-top:0;margin-bottom:0"><font size=3D"2"><span style=3D"fo=
nt-size:11pt;"><i>I do have other thoughts to approach greed that I have not=
 yet made formal on this list, much unrelated to your proposal, but, I see f=
reedom of use of Bitcoin needing to
 be censorship resistant but not necessarily mining provided it is protected=
 enough or free or flexible enough to allow for, say, 50k globally distribut=
ed standard mining hardware units to exist operating at any one time profita=
bly. That said, I am PoW only
 and not PoS orientated.</i></span></font><br>
</p>
</div>
<hr style=3D"display:inline-block;width:98%" tabindex=3D"-1">
<div id=3D"divRplyFwdMsg" dir=3D"ltr"><font face=3D"Calibri, sans-serif" sty=
le=3D"font-size:11pt" color=3D"#000000"><b>From:</b> <a href=3D"mailto:akara=
maoun@gmail.com">akaramaoun@gmail.com</a> &lt;<a href=3D"mailto:akaramaoun@g=
mail.com">akaramaoun@gmail.com</a>&gt; on behalf of Andrew &lt;<a href=3D"ma=
ilto:onelineproof@gmail.com">onelineproof@gmail.com</a>&gt;<br>
<b>Sent:</b> Sunday, 16 September 2018 2:01:19 AM<br>
<b>To:</b> Damian Williamson<br>
<b>Cc:</b> Bitcoin Protocol Discussion<br>
<b>Subject:</b> Re: [bitcoin-dev] Selfish Mining Prevention</font>
<div>&nbsp;</div>
</div>
<div class=3D"BodyFragment"><font size=3D"2"><span style=3D"font-size:11pt;"=
>
<div class=3D"PlainText">@Moral Agent: No problem. I did ask in the first po=
st what the current<br>
plans are for selfish miner prevention. So if anyone has any other<br>
relevant ideas (not just for selfish mining but for making mining more<br>
decentralized and competetive), then please post it, but I just prefer<br>
to focus on my proposal more than others.<br>
<br>
@Damian: I think you are concerned that this will incentivize more<br>
global resource consumption and will be detrimental to our<br>
environment? Personally, I believe centralization of energy does more<br>
harm to the environment rather than total energy consumption. If<br>
Bitcoin helps "power" to become more decentralized, then I wouldn't be<br>
surprised if total (global) energy consumption actually decreases. The<br>
debt based economy is forcing us to continuously grow and use up more<br>
resources, and collectivism is turning individuals into<br>
super-organisms capable of doing much more harm to the environment<br>
than can be done by one or a just a few individuals working<br>
independently. In my proposal, I actually allow for changing<br>
environmental conditions by measuring only the peak hashrate of the<br>
past year, and not the full history of blocks.<br>
<br>
On Sat, Sep 15, 2018 at 5:29 AM, Damian Williamson &lt;<a href=3D"mailto:wil=
ltech@live.com.au">willtech@live.com.au</a>&gt; wrote:<br>
&gt;&gt;This "reserve" part of the fee will be paid to miners if the hashrat=
e<br>
&gt;&gt; rises.<br>
&gt;<br>
&gt;<br>
&gt; Anticipating ongoing hashrate rise shows that you have not yet thought a=
bout<br>
&gt; moving outside of the current greed model, a model wherein mining will<=
br>
&gt; consume all available resources within the colony's objective just to s=
pread<br>
&gt; as far as possible with each new miner bringing diminishing individual<=
br>
&gt; returns and shortening the life of Earth for no additional gain. Greed m=
odel<br>
&gt; :=3D bacteria.<br>
&gt;<br>
&gt; ________________________________<br>
&gt; From: <a href=3D"mailto:bitcoin-dev-bounces@lists.linuxfoundation.org">=
bitcoin-dev-bounces@lists.linuxfoundation.org</a><br>
&gt; &lt;<a href=3D"mailto:bitcoin-dev-bounces@lists.linuxfoundation.org">bi=
tcoin-dev-bounces@lists.linuxfoundation.org</a>&gt; on behalf of Andrew via<=
br>
&gt; bitcoin-dev &lt;<a href=3D"mailto:bitcoin-dev@lists.linuxfoundation.org=
">bitcoin-dev@lists.linuxfoundation.org</a>&gt;<br>
&gt; Sent: Friday, 14 September 2018 9:19:37 AM<br>
&gt; To: Bitcoin Dev<br>
&gt; Subject: Re: [bitcoin-dev] Selfish Mining Prevention<br>
&gt;<br>
&gt; I discussed this more at bitcointalk:<br>
&gt; <a href=3D"https://bitcointalk.org/index.php?topic=3D4998410.0">https:/=
/bitcointalk.org/index.php?topic=3D4998410.0</a><br>
&gt;<br>
&gt; The attacks I'm interested in preventing are not only selfish mining<br=
>
&gt; and collusion, but also more subtle attacks like block withholding,<br>=

&gt; and in general anything that aims to drive out the competition in<br>
&gt; order to increase hashrate fraction. I also scrapped the idea of<br>
&gt; changing the block subsidies, and I am only focuses on fees.<br>
&gt;<br>
&gt; You can read more about the motivation and details in the bitcointalk<b=
r>
&gt; thread, but my proposal in short would be to add the concept of<br>
&gt; "reserve fees". When a user makes a transaction, for each txout<br>
&gt; script, they can add parameters that specify the fraction of the total<=
br>
&gt; fee that is held in "reserve" and the time it is held in "reserve"<br>
&gt; (can set a limit of 2016 blocks). This "reserve" part of the fee will<b=
r>
&gt; be paid to miners if the hashrate rises. So if hashrate is currently h<=
br>
&gt; and peak hashrate (from past year) is p, then for each period (1 day),<=
br>
&gt; a new hashrate is calculated h1, and if h1 &gt; h, then the fraction<br=
>
&gt; (h1-h)/p from the reserve fees created in the past 2016 blocks will be<=
br>
&gt; released to miners for that period (spread out over the 144 blocks in<b=
r>
&gt; that period). And this will keep happening as long as hashrate keeps<br=
>
&gt; rising, until the "contract" expires, and the leftover part can be<br>
&gt; used by the owner of the unspent output, but it can only be used for<br=
>
&gt; paying fees, not as inputs for future transactions (to save on block<br=
>
&gt; space).<br>
&gt;<br>
&gt; This should incentivize miners to not drive out the competition, since<=
br>
&gt; if they do, there will be less of these reserve fees given to miners.<b=
r>
&gt; Yes in the end the miners will get all the fees, but with rising<br>
&gt; hashrate they get an unconditional subsidy that does not require<br>
&gt; transactions, thus more space for transactions with fees.<br>
&gt;<br>
&gt; I can make a formal BIP and pull request, but I need to know if there<b=
r>
&gt; is interest in this. Now fees don't play such a large part of the<br>
&gt; block reward, but they will get more important, and this change<br>
&gt; wouldn't force anything (would be voluntary by each user), just miners<=
br>
&gt; have to agree to it with a soft fork (so they don't spend from the<br>
&gt; anyone-can-spend outputs used for reserve fees). Resource requirements<=
br>
&gt; for validation are quite small I believe.<br>
&gt;<br>
&gt; On Sat, Sep 1, 2018 at 12:11 AM, Andrew &lt;<a href=3D"mailto:onelinepr=
oof@gmail.com">onelineproof@gmail.com</a>&gt; wrote:<br>
&gt;&gt; As I understand, selfish mining is an attack where miners collude t=
o<br>
&gt;&gt; mine at a lower hashrate then with all miners working independently=
.<br>
&gt;&gt; What are the current strategies used to prevent this and what are t=
he<br>
&gt;&gt; future plans?<br>
&gt;&gt;<br>
&gt;&gt; One idea I have is to let the block reward get "modulated" accordin=
g<br>
&gt;&gt; to peak hashrate. Say p is the peak hashrate for 365 periods (1 yea=
r)<br>
&gt;&gt; consisting of 144 blocks, h is the hashrate of the last 144 block (=
1<br>
&gt;&gt; day) period, and r is the base subsidy (12.5 BTC currently). You ca=
n<br>
&gt;&gt; then make the max block reward 0.5 r (1 + h/p). So if hashrate is a=
t<br>
&gt;&gt; peak you get the full reward. Otherwise you get less, down to a min=
 of<br>
&gt;&gt; 0.5 r.<br>
&gt;&gt;<br>
&gt;&gt; If miners were to collude to mine at a lower than peak hashrate, th=
en<br>
&gt;&gt; they may be able to do it profitably for 144 blocks, but after that=
,<br>
&gt;&gt; the reward would get modulated and it wouldn't be so much in their<=
br>
&gt;&gt; interest to continue mining at the lower hashrate.<br>
&gt;&gt;<br>
&gt;&gt; What flaws are there with this? I know it could be controversial du=
e<br>
&gt;&gt; to easier mining present for early miners, so maybe it would have t=
o<br>
&gt;&gt; be done in combination with a new more dynamic difficulty adjustmen=
t<br>
&gt;&gt; algorithm. But I don't see how hashrate can continue rising<br>
&gt;&gt; indefinitely, so a solution should be made for selfish mining.<br>
&gt;&gt;<br>
&gt;&gt; Also when subsidies stop and a fee market is needed, I guess a port=
ion<br>
&gt;&gt; of the fees can be withheld for later if hashrate is not at peak.<b=
r>
&gt;&gt;<br>
&gt;&gt;<br>
&gt;&gt; --<br>
&gt;&gt; PGP: B6AC 822C 451D 6304 6A28&nbsp; 49E9 7DB7 011C D53B 5647<br>
&gt;<br>
&gt;<br>
&gt;<br>
&gt; --<br>
&gt; PGP: B6AC 822C 451D 6304 6A28&nbsp; 49E9 7DB7 011C D53B 5647<br>
&gt; _______________________________________________<br>
&gt; bitcoin-dev mailing list<br>
&gt; <a href=3D"mailto:bitcoin-dev@lists.linuxfoundation.org">bitcoin-dev@li=
sts.linuxfoundation.org</a><br>
&gt; <a href=3D"https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-d=
ev">https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev</a><br>
<br>
<br>
<br>
-- <br>
PGP: B6AC 822C 451D 6304 6A28&nbsp; 49E9 7DB7 011C D53B 5647<br>
</div>
</span></font></div>


</div></blockquote><blockquote type=3D"cite"><div><span>____________________=
___________________________</span><br><span>bitcoin-dev mailing list</span><=
br><span><a href=3D"mailto:bitcoin-dev@lists.linuxfoundation.org">bitcoin-de=
v@lists.linuxfoundation.org</a></span><br><span><a href=3D"https://lists.lin=
uxfoundation.org/mailman/listinfo/bitcoin-dev">https://lists.linuxfoundation=
.org/mailman/listinfo/bitcoin-dev</a></span><br></div></blockquote></body></=
html>=

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