[Bitcoin-development] Bitcoin difficulty sanity check suggestion

[Bitcoin-development] Bitcoin difficulty sanity check suggestion

[Ryan Carboni]

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I think Bitcoin should have a sanity check: after three days if only four
blocks have been mined, difficulty should be adjusted downwards.

This might become important in the near future. I project a Bitcoin mining
bubble.

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Re: [Bitcoin-development] Bitcoin difficulty sanity check suggestion

[Mark Friedenbach]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Ryan, these sort of adjustments introduce security risks. If you were
isolated from the main chain by a low-hashpower attacker, how would
you know? They'd need just three days without you noticing that
network block generation has stalled - maybe they wait for a long
weekend - then after that the block rate is normal but completely
controlled by the attacker (and isolated from mainnet).

There are fast acting alternative difficulty adjustment algorithms
being explored by some alts, such as the 9-block interval, 144-block
window, Parks-McClellan FIR filter used by Freicoin to recover from
just such a mining bubble. If it were to happen to bitcoin, there
would be sophisticated alternative to turn to, and enough time to make
the change.

On 12/22/2013 07:10 PM, Ryan Carboni wrote:
> I think Bitcoin should have a sanity check: after three days if
> only four blocks have been mined, difficulty should be adjusted
> downwards.
> 
> This might become important in the near future. I project a
> Bitcoin mining bubble.
> 
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Re: [Bitcoin-development] Bitcoin difficulty sanity check suggestion

[Robin Ranjit Singh Chauhan]

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Mark, thank you for a very clear explanation of why this proposal would be
dangerous.

What I have noted in many discussions regarding blockchain security and
proof-or-work schemes, is there is a wide gulf between those few people who
can clearly reason about it, and those who have a lot trouble with it (I
mostly fall into the later camp).

I wonder if anyone can point to resources who can help "the rest of us"
reason clearly about these types of proposals, prior to bringing them to
this list or a senior dev.

Ideally it would illustrate various past proposals, explain why they would
and wouldnt work, and build up some fundamental concepts, like a "Newtons
laws of blockchain security" that would help us evaluate such ideas on our
own.

Blockchain stuff is often counterintuitive.



On Sun, Dec 22, 2013 at 7:22 PM, Mark Friedenbach <mark@monetize.io> wrote:

> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> Ryan, these sort of adjustments introduce security risks. If you were
> isolated from the main chain by a low-hashpower attacker, how would
> you know? They'd need just three days without you noticing that
> network block generation has stalled - maybe they wait for a long
> weekend - then after that the block rate is normal but completely
> controlled by the attacker (and isolated from mainnet).
>
> There are fast acting alternative difficulty adjustment algorithms
> being explored by some alts, such as the 9-block interval, 144-block
> window, Parks-McClellan FIR filter used by Freicoin to recover from
> just such a mining bubble. If it were to happen to bitcoin, there
> would be sophisticated alternative to turn to, and enough time to make
> the change.
>
> On 12/22/2013 07:10 PM, Ryan Carboni wrote:
> > I think Bitcoin should have a sanity check: after three days if
> > only four blocks have been mined, difficulty should be adjusted
> > downwards.
> >
> > This might become important in the near future. I project a
> > Bitcoin mining bubble.
> >
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>
>
> ------------------------------------------------------------------------------
> Rapidly troubleshoot problems before they affect your business. Most IT
> organizations don't have a clear picture of how application performance
> affects their revenue. With AppDynamics, you get 100% visibility into your
> Java,.NET, & PHP application. Start your 15-day FREE TRIAL of AppDynamics
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> _______________________________________________
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> Bitcoin-development@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/bitcoin-development
>



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Re: [Bitcoin-development] Bitcoin difficulty sanity check suggestion

[Ryan Carboni]

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I think you misunderstood my statement. If time > 3 days, and after 4
blocks have been mined, then difficulty would be reset.

In theory, one would have to isolate roughly one percent of the Bitcoin
network's hashing power to do so. Which would indicate an attack by a state
actor as opposed to anything else. Arguably, the safest way to run Bitcoin
is through a proprietary dial-up network.


On Sun, Dec 22, 2013 at 7:22 PM, Mark Friedenbach <mark@monetize.io> wrote:

> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> Ryan, these sort of adjustments introduce security risks. If you were
> isolated from the main chain by a low-hashpower attacker, how would
> you know? They'd need just three days without you noticing that
> network block generation has stalled - maybe they wait for a long
> weekend - then after that the block rate is normal but completely
> controlled by the attacker (and isolated from mainnet).
>
> There are fast acting alternative difficulty adjustment algorithms
> being explored by some alts, such as the 9-block interval, 144-block
> window, Parks-McClellan FIR filter used by Freicoin to recover from
> just such a mining bubble. If it were to happen to bitcoin, there
> would be sophisticated alternative to turn to, and enough time to make
> the change.
>
> On 12/22/2013 07:10 PM, Ryan Carboni wrote:
> > I think Bitcoin should have a sanity check: after three days if
> > only four blocks have been mined, difficulty should be adjusted
> > downwards.
> >
> > This might become important in the near future. I project a
> > Bitcoin mining bubble.
> >
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Re: [Bitcoin-development] Bitcoin difficulty sanity check suggestion

[Allen Piscitello]

[-- Attachment #1: Type: text/plain, Size: 3599 bytes --]

Ryan,

Why do you continue to try to correct people who clearly have put more
thought into this than you?  Everyone understood you just fine, you just
seem to have trouble comprehending why your ideas are terrible.


On Mon, Dec 23, 2013 at 7:51 PM, Ryan Carboni <ryan.jc.pc@gmail.com> wrote:

> I think you misunderstood my statement. If time > 3 days, and after 4
> blocks have been mined, then difficulty would be reset.
>
> In theory, one would have to isolate roughly one percent of the Bitcoin
> network's hashing power to do so. Which would indicate an attack by a state
> actor as opposed to anything else. Arguably, the safest way to run Bitcoin
> is through a proprietary dial-up network.
>
>
> On Sun, Dec 22, 2013 at 7:22 PM, Mark Friedenbach <mark@monetize.io>wrote:
>
>> -----BEGIN PGP SIGNED MESSAGE-----
>> Hash: SHA1
>>
>> Ryan, these sort of adjustments introduce security risks. If you were
>> isolated from the main chain by a low-hashpower attacker, how would
>> you know? They'd need just three days without you noticing that
>> network block generation has stalled - maybe they wait for a long
>> weekend - then after that the block rate is normal but completely
>> controlled by the attacker (and isolated from mainnet).
>>
>> There are fast acting alternative difficulty adjustment algorithms
>> being explored by some alts, such as the 9-block interval, 144-block
>> window, Parks-McClellan FIR filter used by Freicoin to recover from
>> just such a mining bubble. If it were to happen to bitcoin, there
>> would be sophisticated alternative to turn to, and enough time to make
>> the change.
>>
>> On 12/22/2013 07:10 PM, Ryan Carboni wrote:
>> > I think Bitcoin should have a sanity check: after three days if
>> > only four blocks have been mined, difficulty should be adjusted
>> > downwards.
>> >
>> > This might become important in the near future. I project a
>> > Bitcoin mining bubble.
>> >
>> -----BEGIN PGP SIGNATURE-----
>> Version: GnuPG v1.4.14 (GNU/Linux)
>> Comment: GPGTools - http://gpgtools.org
>> Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/
>>
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>> =5Q2H
>> -----END PGP SIGNATURE-----
>>
>
>
>
> ------------------------------------------------------------------------------
> Rapidly troubleshoot problems before they affect your business. Most IT
> organizations don't have a clear picture of how application performance
> affects their revenue. With AppDynamics, you get 100% visibility into your
> Java,.NET, & PHP application. Start your 15-day FREE TRIAL of AppDynamics
> Pro!
> http://pubads.g.doubleclick.net/gampad/clk?id=84349831&iu=/4140/ostg.clktrk
> _______________________________________________
> Bitcoin-development mailing list
> Bitcoin-development@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/bitcoin-development
>
>

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Re: [Bitcoin-development] Bitcoin difficulty sanity check suggestion

[Ryan Carboni]

[-- Attachment #1: Type: text/plain, Size: 4069 bytes --]

Maybe it's because the arguments being presented are nonsensical and
irrelevant to the current Bitcoin network topology, composed of a small
number of mining pools, not solo miners? Furthermore I think people would
realize that their mining pool has gone "off the reservation" so to speak.


On Mon, Dec 23, 2013 at 8:05 PM, Allen Piscitello <
allen.piscitello@gmail.com> wrote:

> Ryan,
>
> Why do you continue to try to correct people who clearly have put more
> thought into this than you?  Everyone understood you just fine, you just
> seem to have trouble comprehending why your ideas are terrible.
>
>
> On Mon, Dec 23, 2013 at 7:51 PM, Ryan Carboni <ryan.jc.pc@gmail.com>wrote:
>
>> I think you misunderstood my statement. If time > 3 days, and after 4
>> blocks have been mined, then difficulty would be reset.
>>
>> In theory, one would have to isolate roughly one percent of the Bitcoin
>> network's hashing power to do so. Which would indicate an attack by a state
>> actor as opposed to anything else. Arguably, the safest way to run Bitcoin
>> is through a proprietary dial-up network.
>>
>>
>> On Sun, Dec 22, 2013 at 7:22 PM, Mark Friedenbach <mark@monetize.io>wrote:
>>
>>> -----BEGIN PGP SIGNED MESSAGE-----
>>> Hash: SHA1
>>>
>>> Ryan, these sort of adjustments introduce security risks. If you were
>>> isolated from the main chain by a low-hashpower attacker, how would
>>> you know? They'd need just three days without you noticing that
>>> network block generation has stalled - maybe they wait for a long
>>> weekend - then after that the block rate is normal but completely
>>> controlled by the attacker (and isolated from mainnet).
>>>
>>> There are fast acting alternative difficulty adjustment algorithms
>>> being explored by some alts, such as the 9-block interval, 144-block
>>> window, Parks-McClellan FIR filter used by Freicoin to recover from
>>> just such a mining bubble. If it were to happen to bitcoin, there
>>> would be sophisticated alternative to turn to, and enough time to make
>>> the change.
>>>
>>> On 12/22/2013 07:10 PM, Ryan Carboni wrote:
>>> > I think Bitcoin should have a sanity check: after three days if
>>> > only four blocks have been mined, difficulty should be adjusted
>>> > downwards.
>>> >
>>> > This might become important in the near future. I project a
>>> > Bitcoin mining bubble.
>>> >
>>> -----BEGIN PGP SIGNATURE-----
>>> Version: GnuPG v1.4.14 (GNU/Linux)
>>> Comment: GPGTools - http://gpgtools.org
>>> Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/
>>>
>>> iQIcBAEBAgAGBQJSt6yGAAoJEAdzVfsmodw4SegQAIJAWW0OgSjediSWq+EpkReS
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>>> DOTF7jpt0ZmCm7uhG9z7
>>> =5Q2H
>>> -----END PGP SIGNATURE-----
>>>
>>
>>
>>
>> ------------------------------------------------------------------------------
>> Rapidly troubleshoot problems before they affect your business. Most IT
>> organizations don't have a clear picture of how application performance
>> affects their revenue. With AppDynamics, you get 100% visibility into your
>> Java,.NET, & PHP application. Start your 15-day FREE TRIAL of AppDynamics
>> Pro!
>>
>> http://pubads.g.doubleclick.net/gampad/clk?id=84349831&iu=/4140/ostg.clktrk
>> _______________________________________________
>> Bitcoin-development mailing list
>> Bitcoin-development@lists.sourceforge.net
>> https://lists.sourceforge.net/lists/listinfo/bitcoin-development
>>
>>
>

[-- Attachment #2: Type: text/html, Size: 5640 bytes --]

Re: [Bitcoin-development] Bitcoin difficulty sanity check suggestion

[Gavin Costin]

[-- Attachment #1.1: Type: text/plain, Size: 5271 bytes --]

Ryan,

Maybe you could test out your ideas somewhere like bitcointalk.org and/or provide some more technical substance before engaging with this forum.

Developers tend to prefer dealing with numbers known to be either 1 or 0, not a variable set of possible values depending on non-technical factors ...

Gavin

> On 24/12/2013, at 15:42, "Ryan Carboni" <ryan.jc.pc@gmail.com> wrote:
> 
> Maybe it's because the arguments being presented are nonsensical and irrelevant to the current Bitcoin network topology, composed of a small number of mining pools, not solo miners? Furthermore I think people would realize that their mining pool has gone "off the reservation" so to speak.
> 
> 
>> On Mon, Dec 23, 2013 at 8:05 PM, Allen Piscitello <allen.piscitello@gmail.com> wrote:
>> Ryan,
>> 
>> Why do you continue to try to correct people who clearly have put more thought into this than you?  Everyone understood you just fine, you just seem to have trouble comprehending why your ideas are terrible.
>> 
>> 
>>> On Mon, Dec 23, 2013 at 7:51 PM, Ryan Carboni <ryan.jc.pc@gmail.com> wrote:
>>> I think you misunderstood my statement. If time > 3 days, and after 4 blocks have been mined, then difficulty would be reset.
>>> 
>>> In theory, one would have to isolate roughly one percent of the Bitcoin network's hashing power to do so. Which would indicate an attack by a state actor as opposed to anything else. Arguably, the safest way to run Bitcoin is through a proprietary dial-up network.
>>> 
>>> 
>>>> On Sun, Dec 22, 2013 at 7:22 PM, Mark Friedenbach <mark@monetize.io> wrote:
>>> 
>>>> -----BEGIN PGP SIGNED MESSAGE-----
>>>> Hash: SHA1
>>>> 
>>>> Ryan, these sort of adjustments introduce security risks. If you were
>>>> isolated from the main chain by a low-hashpower attacker, how would
>>>> you know? They'd need just three days without you noticing that
>>>> network block generation has stalled - maybe they wait for a long
>>>> weekend - then after that the block rate is normal but completely
>>>> controlled by the attacker (and isolated from mainnet).
>>>> 
>>>> There are fast acting alternative difficulty adjustment algorithms
>>>> being explored by some alts, such as the 9-block interval, 144-block
>>>> window, Parks-McClellan FIR filter used by Freicoin to recover from
>>>> just such a mining bubble. If it were to happen to bitcoin, there
>>>> would be sophisticated alternative to turn to, and enough time to make
>>>> the change.
>>>> 
>>>> On 12/22/2013 07:10 PM, Ryan Carboni wrote:
>>>> > I think Bitcoin should have a sanity check: after three days if
>>>> > only four blocks have been mined, difficulty should be adjusted
>>>> > downwards.
>>>> >
>>>> > This might become important in the near future. I project a
>>>> > Bitcoin mining bubble.
>>>> >
>>>> -----BEGIN PGP SIGNATURE-----
>>>> Version: GnuPG v1.4.14 (GNU/Linux)
>>>> Comment: GPGTools - http://gpgtools.org
>>>> Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/
>>>> 
>>>> iQIcBAEBAgAGBQJSt6yGAAoJEAdzVfsmodw4SegQAIJAWW0OgSjediSWq+EpkReS
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>>>> +0e14wPra5blV6yBVqX7yx+2heDGymPKfHJ8i76Dtix7XVOJWKVY4OpIxO7YrYv8
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>>>> j38hojcwvJC1ahER3LV/vC0cqO+fxrvY8Q9rW2cUxCnzxzjjG0+Z/gjW8uh73lXN
>>>> DOTF7jpt0ZmCm7uhG9z7
>>>> =5Q2H
>>>> -----END PGP SIGNATURE-----
>>> 
>>> 
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Re: [Bitcoin-development] Bitcoin difficulty sanity check suggestion

[Ryan Carboni]

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It does take a state-level actor to apparently disconnect *multiple *miners
from the rest of the network.

How many Bitcoin miners hash an entire percent or more of the Bitcoin
network? What you're proposing is an attack at the highest levels of the
internet infrastructure.


On Mon, Dec 23, 2013 at 6:02 PM, Mark Friedenbach <mark@monetize.io> wrote:

> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> Which would leave you entirely in the hands of your dialup provider.
> Or the manufacturer of your switch. Or your ISP's backbone provider.
> It does not take a state-level actor to do network attacks.
>
> BTW, what does "difficulty would be reset" mean? There are multiple
> ways to interpret that statement. In the most straightforward way, my
> objections apply.
>
> On 12/23/2013 05:51 PM, Ryan Carboni wrote:
> > I think you misunderstood my statement. If time > 3 days, and after
> > 4 blocks have been mined, then difficulty would be reset.
> >
> > In theory, one would have to isolate roughly one percent of the
> > Bitcoin network's hashing power to do so. Which would indicate an
> > attack by a state actor as opposed to anything else. Arguably, the
> > safest way to run Bitcoin is through a proprietary dial-up
> > network.
> >
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Re: [Bitcoin-development] Bitcoin difficulty sanity check suggestion

[Matt Corallo]

An attacker with some small hashpower isolates you (as an individual)
from the network by MITMing your network. You just switch the the
attackers chain as if nothing happened because of the network rule
that defines it as OK. Today, you will see that you're behind and warn
the user.

Was it really so hard to write a three-sentence paragraph to clarify
the attack instead of insulting people? Still, posting ideas here
without spending time to ensure you understand the Bitcoin network
well is frowned upon.

Matt

On 12/23/13 17:51, Ryan Carboni wrote:
> I think you misunderstood my statement. If time > 3 days, and after
> 4 blocks have been mined, then difficulty would be reset.
> 
> In theory, one would have to isolate roughly one percent of the
> Bitcoin network's hashing power to do so. Which would indicate an
> attack by a state actor as opposed to anything else. Arguably, the
> safest way to run Bitcoin is through a proprietary dial-up
> network.
> 
> 
> On Sun, Dec 22, 2013 at 7:22 PM, Mark Friedenbach
> <mark@monetize.io <mailto:mark@monetize.io>> wrote:
> 
> Ryan, these sort of adjustments introduce security risks. If you
> were isolated from the main chain by a low-hashpower attacker, how
> would you know? They'd need just three days without you noticing
> that network block generation has stalled - maybe they wait for a
> long weekend - then after that the block rate is normal but
> completely controlled by the attacker (and isolated from mainnet).
> 
> There are fast acting alternative difficulty adjustment algorithms 
> being explored by some alts, such as the 9-block interval,
> 144-block window, Parks-McClellan FIR filter used by Freicoin to
> recover from just such a mining bubble. If it were to happen to
> bitcoin, there would be sophisticated alternative to turn to, and
> enough time to make the change.
> 
> On 12/22/2013 07:10 PM, Ryan Carboni wrote:
>> I think Bitcoin should have a sanity check: after three days if 
>> only four blocks have been mined, difficulty should be adjusted 
>> downwards.
> 
>> This might become important in the near future. I project a 
>> Bitcoin mining bubble.
> 
> 
> 
> 
> 
> ------------------------------------------------------------------------------
>
> 
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> 
> 
> 
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