Re: [Bitcoin-development] Economics of information propagation

[Daniel Lidstrom <lidstrom83@gmail.com>]

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If this policy of mining empty blocks upon new block headers before
downloading and verifying the blocks became the standard, then wouldn't the
marginal orphan probability per transaction vanish?  It seems like this
could be a way to seriously reduce transaction fees.


On Sun, Apr 20, 2014 at 10:44 PM, Daniel Lidstrom <lidstrom83@gmail.com>wrote:

>
> Of course, in reality smaller miners can just mine on top of block headers
>> and include no transactions and do no validation, but that is extremely
>> harmful to the security of Bitcoin.
>
>
> If it's only during the few seconds that it takes to to verify the block,
> then would this really be that big of a deal?  E.g. even if all miners did
> this, a 10 second delay would only yield an average of a couple blind/empty
> blocks per day.
>
>
> On Sun, Apr 20, 2014 at 10:06 PM, Peter Todd <pete@petertodd.org> wrote:
>
>> -----BEGIN PGP SIGNED MESSAGE-----
>> Hash: SHA256
>>
>> That is mistaken: you can't mine on top of just a block header, leaving
>> small miners disadvantaged as they are earning no profit while they wait
>> for the information to validate the block and update their UTXO sets. This
>> results in the same problem as before, as the large pools who mine most
>> blocks can validate either instantly - the self-mine case - or more quickly
>> than the smaller miners.
>>
>> Of course, in reality smaller miners can just mine on top of block
>> headers and include no transactions and do no validation, but that is
>> extremely harmful to the security of Bitcoin.
>>
>>
>> On 20 April 2014 23:58:58 GMT-04:00, Mark Friedenbach <mark@monetize.io>
>> wrote:
>> >As soon as we switch to headers
>> >first - which will be soon - there will be no difference in propagation
>> >time no matter how large the block is. Only 80 bites will be required
>> >to
>> >propagate the block header which establishes priority for when the
>> >block is
>> >fully validated.
>> >On Apr 20, 2014 6:56 PM, "Jonathan Levin"
>> ><jonathan.levin@sant.ox.ac.uk>
>> >wrote:
>> >
>> >> Hi all,
>> >>
>> >> I am a post-graduate economist writing a paper on the incentives of
>> >> mining. Even though this issue has been debated in the forums, I
>> >think it
>> >> is important to get a sense of the magnitude of the incentives at
>> >play and
>> >> determine what implications this has for the transaction fee market.
>> >>
>> >> As it has been pointed out before the marginal cost for miners does
>> >not
>> >> stem from the private cost of the miner validating the signature and
>> >> including it in the list of transactions in the block but rather the
>> >> increased probability that the block will be orphaned as a result of
>> >slower
>> >> propagation. Gavin did some back of the envelope worst case
>> >calculations
>> >> but these overstated the effect of propagation delay. The reason
>> >being the
>> >> 80ms additional time to reach 50% of the network is spread throughout
>> >the
>> >> time that it takes to reach 50% of the network. During this time
>> >miners are
>> >> notified about the block and treat it as the longest chain and hence
>> >are no
>> >> longer mining with the aim to produce a competing block.
>> >>
>> >> I am looking to calculate the change in the curvature of the
>> >probability
>> >> mass function that a block hears about my block in any given second
>> >as a
>> >> function of the block size. Although there is likely to be
>> >significant
>> >> noise here, there seems to be some stable linear relationships with
>> >the
>> >> time that it takes to reach different quartiles. Has anyone done
>> >this? I
>> >> have used some empirical data that I am happy to share but ideally I
>> >would
>> >> like analytical solutions.
>> >>
>> >> Following Peter Todd, I also find the concerning result that
>> >propagation
>> >> delays results in increasing returns to higher shares of the hashing
>> >power.
>> >> Indeed it may well be in the interest of large pools to publish large
>> >> blocks to increase propagation delays on the network which would
>> >increase
>> >> orphan rates particularly for small miners and miners that have not
>> >> invested in sufficient bandwidth / connectivity. If a small miner
>> >hears
>> >> about a block after 4.5 seconds on average there is a 0.7% chance
>> >that
>> >> there is already a block in circulation.  Large miners can increase
>> >the
>> >> time that it takes for small miners to hear about blocks by
>> >increasing the
>> >> size of their blocks. For example if the time that it takes for a
>> >small
>> >> miner to hear about the block goes to 12 seconds there is a 2 percent
>> >> chance there is already a block in circulation for the small miner.
>> >There
>> >> is also a 1.2% chance that there will be a competing block published
>> >after
>> >> a small miner propagates in the time that it gets to full
>> >propagation. Am I
>> >> getting this right that the probability of a miner’s block being
>> >orphaned
>> >> is comprised of the probability that the miner was not the first to
>> >find a
>> >> valid block and the probability that given they are first, someone
>> >else in
>> >> the absence of hearing about it finds a competing valid block.
>> >>
>> >> One question is: Are orphans probabilistic and only resolved after
>> >hearing
>> >> about a new block that lengthens the chain or is there a way to know
>> >in
>> >> advance? Is it frowned upon to mine on top of a block that you have
>> >just
>> >> found even though it is very likely going to end up an orphan?
>> >>
>> >> Would be happy to share the draft form of the paper and receive any
>> >> feedback.
>> >>
>> >> Finally, at coinometrics we are working on a modified client to
>> >capture
>> >> information on network propagation and would invite any suggestions
>> >of any
>> >> other useful statistics that would be useful in the development of
>> >software.
>> >>
>> >> Best,
>> >>
>> >> Jonathan
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >>
>> >> On 21 Apr 2014, at 01:16, <
>> >> bitcoin-development-request@lists.sourceforge.net> <
>> >> bitcoin-development-request@lists.sourceforge.net> wrote:
>> >>
>> >> > Send Bitcoin-development mailing list submissions to
>> >> >       bitcoin-development@lists.sourceforge.net
>> >> >
>> >> > To subscribe or unsubscribe via the World Wide Web, visit
>> >> >
>> >https://lists.sourceforge.net/lists/listinfo/bitcoin-development
>> >> > or, via email, send a message with subject or body 'help' to
>> >> >       bitcoin-development-request@lists.sourceforge.net
>> >> >
>> >> > You can reach the person managing the list at
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>> >> >
>> >> > When replying, please edit your Subject line so it is more specific
>> >> > than "Re: Contents of Bitcoin-development digest..."
>> >> >
>> >> >
>> >> > Today's Topics:
>> >> >
>> >> >   1. Re: "bits": Unit of account (Oliver Egginger)
>> >> >   2. Re: "bits": Unit of account (Christophe Biocca)
>> >> >   3. Re: "bits": Unit of account (Gmail)
>> >> >   4. Re: "bits": Unit of account (Mike Caldwell)
>> >> >   5. Re: "bits": Unit of account (Justin A)
>> >> >
>> >> >
>> >> >
>> >----------------------------------------------------------------------
>> >> >
>> >> > Message: 1
>> >> > Date: Sun, 20 Apr 2014 20:43:24 +0200
>> >> > From: Oliver Egginger <bitcoin@olivere.de>
>> >> > Subject: Re: [Bitcoin-development] "bits": Unit of account
>> >> > To: Bitcoin Development <bitcoin-development@lists.sourceforge.net>
>> >> > Message-ID: <5354154C.1080908@olivere.de>
>> >> > Content-Type: text/plain; charset=ISO-8859-1
>> >> >
>> >> > Hello,
>> >> >
>> >> > just my two 'cents':
>> >> >
>> >> > Terms arises by itself. Just as most people speak of coins when
>> >they
>> >> > mean bitcoins. I do not see that bitcoin is currently in common use
>> >> > except for speculation. Therefore no term for smaller units has
>> >> > established yet. No problem in my eyes. Time will tell.
>> >> >
>> >> > - oliver
>> >> >
>> >> >
>> >> >
>> >> >
>> >> > ------------------------------
>> >> >
>> >> > Message: 2
>> >> > Date: Sun, 20 Apr 2014 15:19:38 -0400
>> >> > From: Christophe Biocca <christophe.biocca@gmail.com>
>> >> > Subject: Re: [Bitcoin-development] "bits": Unit of account
>> >> > To: Bitcoin Development <bitcoin-development@lists.sourceforge.net>
>> >> > Message-ID:
>> >> >       <CANOOu=9=
>> >> TAnaCuyh_P2GqHaguyY39xjhj84HSA_x+6F4MOqM_A@mail.gmail.com>
>> >> > Content-Type: text/plain; charset=UTF-8
>> >> >
>> >> > Culturally neutral? "bit" in French phonetically collides with
>> >slang
>> >> > for phallus ("bitte", with a silent "e"). Apparently it means
>> >"louse"
>> >> > in Turkish as well.
>> >> >
>> >> > Not that this really would be avoidable with any short word (all
>> >the
>> >> > short possible words are usually taken), but it's not neutral.
>> >> >
>> >> > On Sun, Apr 20, 2014 at 2:43 PM, Oliver Egginger
>> ><bitcoin@olivere.de>
>> >> wrote:
>> >> >> Hello,
>> >> >>
>> >> >> just my two 'cents':
>> >> >>
>> >> >> Terms arises by itself. Just as most people speak of coins when
>> >they
>> >> >> mean bitcoins. I do not see that bitcoin is currently in common
>> >use
>> >> >> except for speculation. Therefore no term for smaller units has
>> >> >> established yet. No problem in my eyes. Time will tell.
>> >> >>
>> >> >> - oliver
>> >> >>
>> >> >>
>> >> >>
>> >>
>>
>> >------------------------------------------------------------------------------
>> >> >> Learn Graph Databases - Download FREE O'Reilly Book
>> >> >> "Graph Databases" is the definitive new guide to graph databases
>> >and
>> >> their
>> >> >> applications. Written by three acclaimed leaders in the field,
>> >> >> this first edition is now available. Download your free book
>> >today!
>> >> >> http://p.sf.net/sfu/NeoTech
>> >> >> _______________________________________________
>> >> >> Bitcoin-development mailing list
>> >> >> Bitcoin-development@lists.sourceforge.net
>> >> >> https://lists.sourceforge.net/lists/listinfo/bitcoin-development
>> >> >
>> >> >
>> >> >
>> >> > ------------------------------
>> >> >
>> >> > Message: 3
>> >> > Date: Sun, 20 Apr 2014 14:32:26 -0500
>> >> > From: Gmail <will.yager@gmail.com>
>> >> > Subject: Re: [Bitcoin-development] "bits": Unit of account
>> >> > Cc: Bitcoin Development <bitcoin-development@lists.sourceforge.net>
>> >> > Message-ID: <B687D4AD-263F-4594-BE7A-FF238B8DF7AF@gmail.com>
>> >> > Content-Type: text/plain; charset="us-ascii"
>> >> >
>> >> > People in the Bitcoin community are sometimes resistant to the idea
>> >of
>> >> using the word "credit" as a unit of Bitcoin, because Bitcoin is not
>> >a
>> >> credit-based system.
>> >> >
>> >> > However, given that the average person has close to no
>> >understanding of
>> >> what "credit" means, and probably no concern for the distinction even
>> >if
>> >> they do know, it may be wise to use the futuristic and easily
>> >> understandable "credit" as our human-friendly unit.
>> >> >
>> >> > Do others agree that "credits" as a unit of account has a desirable
>> >> futuristic connotation?
>> >> >
>> >> > Will
>> >> >
>> >> > -------------- next part --------------
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>> >> >
>> >> > ------------------------------
>> >> >
>> >> > Message: 4
>> >> > Date: Sun, 20 Apr 2014 16:28:34 -0400
>> >> > From: Mike Caldwell <mcaldwell@swipeclock.com>
>> >> > Subject: Re: [Bitcoin-development] "bits": Unit of account
>> >> > To: Christophe Biocca <christophe.biocca@gmail.com>
>> >> > Cc: Bitcoin Development <bitcoin-development@lists.sourceforge.net>
>> >> > Message-ID: <4098C706-D67F-474E-9C13-E4C8F56B41ED@swipeclock.com>
>> >> > Content-Type: text/plain; charset="us-ascii"
>> >> >
>> >> > By culturally neutral I mean we avoid deliberately invoking a
>> >cultural
>> >> reference in the name.  For example "satoshi" would be a reference to
>> >> Japanese culture just for being a common Japanese name regardless of
>> >who
>> >> Satoshi turns out to be.
>> >> >
>> >> > Mike
>> >> >
>> >> > Sent from my iPhone
>> >> >
>> >> >> On Apr 20, 2014, at 1:20 PM, "Christophe Biocca" <
>> >> christophe.biocca@gmail.com> wrote:
>> >> >>
>> >> >> Culturally neutral? "bit" in French phonetically collides with
>> >slang
>> >> >> for phallus ("bitte", with a silent "e"). Apparently it means
>> >"louse"
>> >> >> in Turkish as well.
>> >> >>
>> >> >> Not that this really would be avoidable with any short word (all
>> >the
>> >> >> short possible words are usually taken), but it's not neutral.
>> >> >>
>> >> >>> On Sun, Apr 20, 2014 at 2:43 PM, Oliver Egginger
>> ><bitcoin@olivere.de>
>> >> wrote:
>> >> >>> Hello,
>> >> >>>
>> >> >>> just my two 'cents':
>> >> >>>
>> >> >>> Terms arises by itself. Just as most people speak of coins when
>> >they
>> >> >>> mean bitcoins. I do not see that bitcoin is currently in common
>> >use
>> >> >>> except for speculation. Therefore no term for smaller units has
>> >> >>> established yet. No problem in my eyes. Time will tell.
>> >> >>>
>> >> >>> - oliver
>> >> >>>
>> >> >>>
>> >> >>>
>> >>
>>
>> >------------------------------------------------------------------------------
>> >> >>> Learn Graph Databases - Download FREE O'Reilly Book
>> >> >>> "Graph Databases" is the definitive new guide to graph databases
>> >and
>> >> their
>> >> >>> applications. Written by three acclaimed leaders in the field,
>> >> >>> this first edition is now available. Download your free book
>> >today!
>> >> >>> http://p.sf.net/sfu/NeoTech
>> >> >>> _______________________________________________
>> >> >>> Bitcoin-development mailing list
>> >> >>> Bitcoin-development@lists.sourceforge.net
>> >> >>> https://lists.sourceforge.net/lists/listinfo/bitcoin-development
>> >> >>
>> >> >>
>> >>
>>
>> >------------------------------------------------------------------------------
>> >> >> Learn Graph Databases - Download FREE O'Reilly Book
>> >> >> "Graph Databases" is the definitive new guide to graph databases
>> >and
>> >> their
>> >> >> applications. Written by three acclaimed leaders in the field,
>> >> >> this first edition is now available. Download your free book
>> >today!
>> >> >> http://p.sf.net/sfu/NeoTech
>> >> >> _______________________________________________
>> >> >> Bitcoin-development mailing list
>> >> >> Bitcoin-development@lists.sourceforge.net
>> >> >> https://lists.sourceforge.net/lists/listinfo/bitcoin-development
>> >> >
>> >> >
>> >> >
>> >> > ------------------------------
>> >> >
>> >> > Message: 5
>> >> > Date: Sun, 20 Apr 2014 20:16:35 -0400
>> >> > From: Justin A <allport@gmail.com>
>> >> > Subject: Re: [Bitcoin-development] "bits": Unit of account
>> >> > To: Mike Caldwell <mcaldwell@swipeclock.com>
>> >> > Cc: Bitcoin Development <bitcoin-development@lists.sourceforge.net>
>> >> > Message-ID:
>> >> >       <
>> >> CAK2MuX3GufxU_AH0Kaw3pUkzgX_agok86ahCh+7r96UkxZwneQ@mail.gmail.com>
>> >> > Content-Type: text/plain; charset="utf-8"
>> >> >
>> >> > <delurk>
>> >> >
>> >> > What about "ubit", pronounced "YOU-bit", representing 1e-6 bitcoin?
>> >Easy
>> >> to
>> >> > say, tied in a visual way to the metric micro, leaves the required
>> >2
>> >> > decimal places for the marginally numerate.. What more could one
>> >want?
>> >> >
>> >> > </delurk>
>> >> >
>> >> > Also, hi. My first post; plan to get involved over the southern
>> >> hemisphere
>> >> > winter if I can learn enough.
>> >> > On Apr 20, 2014 4:32 PM, "Mike Caldwell" <mcaldwell@swipeclock.com>
>> >> wrote:
>> >> >
>> >> >> By culturally neutral I mean we avoid deliberately invoking a
>> >cultural
>> >> >> reference in the name.  For example "satoshi" would be a reference
>> >to
>> >> >> Japanese culture just for being a common Japanese name regardless
>> >of who
>> >> >> Satoshi turns out to be.
>> >> >>
>> >> >> Mike
>> >> >>
>> >> >> Sent from my iPhone
>> >> >>
>> >> >>> On Apr 20, 2014, at 1:20 PM, "Christophe Biocca" <
>> >> >> christophe.biocca@gmail.com> wrote:
>> >> >>>
>> >> >>> Culturally neutral? "bit" in French phonetically collides with
>> >slang
>> >> >>> for phallus ("bitte", with a silent "e"). Apparently it means
>> >"louse"
>> >> >>> in Turkish as well.
>> >> >>>
>> >> >>> Not that this really would be avoidable with any short word (all
>> >the
>> >> >>> short possible words are usually taken), but it's not neutral.
>> >> >>>
>> >> >>>> On Sun, Apr 20, 2014 at 2:43 PM, Oliver Egginger
>> ><bitcoin@olivere.de>
>> >> >> wrote:
>> >> >>>> Hello,
>> >> >>>>
>> >> >>>> just my two 'cents':
>> >> >>>>
>> >> >>>> Terms arises by itself. Just as most people speak of coins when
>> >they
>> >> >>>> mean bitcoins. I do not see that bitcoin is currently in common
>> >use
>> >> >>>> except for speculation. Therefore no term for smaller units has
>> >> >>>> established yet. No problem in my eyes. Time will tell.
>> >> >>>>
>> >> >>>> - oliver
>> >> >>>>
>> >> >>>>
>> >> >>>>
>> >> >>
>> >>
>>
>> >------------------------------------------------------------------------------
>> >> >>>> Learn Graph Databases - Download FREE O'Reilly Book
>> >> >>>> "Graph Databases" is the definitive new guide to graph databases
>> >and
>> >> >> their
>> >> >>>> applications. Written by three acclaimed leaders in the field,
>> >> >>>> this first edition is now available. Download your free book
>> >today!
>> >> >>>> http://p.sf.net/sfu/NeoTech
>> >> >>>> _______________________________________________
>> >> >>>> Bitcoin-development mailing list
>> >> >>>> Bitcoin-development@lists.sourceforge.net
>> >> >>>> https://lists.sourceforge.net/lists/listinfo/bitcoin-development
>> >> >>>
>> >> >>>
>> >> >>
>> >>
>>
>> >------------------------------------------------------------------------------
>> >> >>> Learn Graph Databases - Download FREE O'Reilly Book
>> >> >>> "Graph Databases" is the definitive new guide to graph databases
>> >and
>> >> >> their
>> >> >>> applications. Written by three acclaimed leaders in the field,
>> >> >>> this first edition is now available. Download your free book
>> >today!
>> >> >>> http://p.sf.net/sfu/NeoTech
>> >> >>> _______________________________________________
>> >> >>> Bitcoin-development mailing list
>> >> >>> Bitcoin-development@lists.sourceforge.net
>> >> >>> https://lists.sourceforge.net/lists/listinfo/bitcoin-development
>> >> >>
>> >> >>
>> >> >>
>> >>
>>
>> >------------------------------------------------------------------------------
>> >> >> Learn Graph Databases - Download FREE O'Reilly Book
>> >> >> "Graph Databases" is the definitive new guide to graph databases
>> >and
>> >> their
>> >> >> applications. Written by three acclaimed leaders in the field,
>> >> >> this first edition is now available. Download your free book
>> >today!
>> >> >> http://p.sf.net/sfu/NeoTech
>> >> >> _______________________________________________
>> >> >> Bitcoin-development mailing list
>> >> >> Bitcoin-development@lists.sourceforge.net
>> >> >> https://lists.sourceforge.net/lists/listinfo/bitcoin-development
>> >> >>
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>> >>
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