Jeff Garzik [ARCHIVE] on Nostr: š Original date posted:2014-07-24 š Original message:Miners are free to set the ...
š
Original date posted:2014-07-24
š Original message:Miners are free to set the block's timestamp to whatever they please,
within a certain +/- time window. Time might even go backwards a tiny
bit from the last block to the next block.
On Thu, Jul 24, 2014 at 9:14 PM, Ron OHara <ron.ohara54 at gmail.com> wrote:
>
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> I thought I should shortcut my research by asking a direct question here.
>
> As I understand it, the blockchain actually provides an extra piece of
> reliable data that is not being exploited by applications.
>
> Which data? The time. In this case 'the time' as agreed by >50% of
> the participants, where those participants have a strong financial
> incentive to keep that 'time' fairly accurate. (+/- about 10 minutes)
>
> Is this a reasonable understanding of 'time'? ... aka timestamps on the
> block
>
> Ok... 'time' on the blockchain could be 'gamed' ... but with great
> difficulty. An application presented with a fake blockchain can use
> quite a few heuristics to test the 'validity' of the block chain.
> It can review the usual cryptographic proofs, and check that difficulty
> is growing/declining only in a realistic manner up to the most recent
> block. Even use some arbitrary test like difficulty > 10,000,000,000
> ... on the presumption that any less means that the Bitcoin system has
> failed massively from where it currently is and has become an unreliable
> time source.
>
> Reliable 'time' has been impossible up until now - because you need to
> trust the time source, and that can always be faked. Using the
> blockchain as an approximate time source gives you a world wide
> consensus without direct trust of any player.
>
> So if this presumption is correct, then we can now build time capsule
> applications that can not be tricked into exposing their contents too
> early by running them in a virtual environment with the wrong system time.
>
> Is this right? or did miss I something fundamental?
>
> Ron
>
> - --
> public identify: https://www.onename.io/ron_ohara
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> Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/
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>
> ------------------------------------------------------------------------------
> Want fast and easy access to all the code in your enterprise? Index and
> search up to 200,000 lines of code with a free copy of Black Duck
> Code Sight - the same software that powers the world's largest code
> search on Ohloh, the Black Duck Open Hub! Try it now.
> http://p.sf.net/sfu/bds
> _______________________________________________
> Bitcoin-development mailing list
> Bitcoin-development at lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/bitcoin-development
--
Jeff Garzik
Bitcoin core developer and open source evangelist
BitPay, Inc. https://bitpay.com/
š Original message:Miners are free to set the block's timestamp to whatever they please,
within a certain +/- time window. Time might even go backwards a tiny
bit from the last block to the next block.
On Thu, Jul 24, 2014 at 9:14 PM, Ron OHara <ron.ohara54 at gmail.com> wrote:
>
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> I thought I should shortcut my research by asking a direct question here.
>
> As I understand it, the blockchain actually provides an extra piece of
> reliable data that is not being exploited by applications.
>
> Which data? The time. In this case 'the time' as agreed by >50% of
> the participants, where those participants have a strong financial
> incentive to keep that 'time' fairly accurate. (+/- about 10 minutes)
>
> Is this a reasonable understanding of 'time'? ... aka timestamps on the
> block
>
> Ok... 'time' on the blockchain could be 'gamed' ... but with great
> difficulty. An application presented with a fake blockchain can use
> quite a few heuristics to test the 'validity' of the block chain.
> It can review the usual cryptographic proofs, and check that difficulty
> is growing/declining only in a realistic manner up to the most recent
> block. Even use some arbitrary test like difficulty > 10,000,000,000
> ... on the presumption that any less means that the Bitcoin system has
> failed massively from where it currently is and has become an unreliable
> time source.
>
> Reliable 'time' has been impossible up until now - because you need to
> trust the time source, and that can always be faked. Using the
> blockchain as an approximate time source gives you a world wide
> consensus without direct trust of any player.
>
> So if this presumption is correct, then we can now build time capsule
> applications that can not be tricked into exposing their contents too
> early by running them in a virtual environment with the wrong system time.
>
> Is this right? or did miss I something fundamental?
>
> Ron
>
> - --
> public identify: https://www.onename.io/ron_ohara
> -----BEGIN PGP SIGNATURE-----
> Version: GnuPG v2.0.20 (GNU/Linux)
> Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/
>
> iQEcBAEBAgAGBQJT0a9sAAoJEAla1VT1+xc2ONQH/0R09guSNNCxP36KziAjfcBc
> JEhxMpIlqTTYEvNXaBmuPy4BN+IZQ9izgrW/cvlEJJNMmc5/VIBk83WZltmDwcKl
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> =T5fw
> -----END PGP SIGNATURE-----
>
>
> ------------------------------------------------------------------------------
> Want fast and easy access to all the code in your enterprise? Index and
> search up to 200,000 lines of code with a free copy of Black Duck
> Code Sight - the same software that powers the world's largest code
> search on Ohloh, the Black Duck Open Hub! Try it now.
> http://p.sf.net/sfu/bds
> _______________________________________________
> Bitcoin-development mailing list
> Bitcoin-development at lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/bitcoin-development
--
Jeff Garzik
Bitcoin core developer and open source evangelist
BitPay, Inc. https://bitpay.com/