public inbox for bitcoindev@googlegroups.com
 help / color / mirror / Atom feed
From: Ron OHara <ron.ohara54@gmail.com>
To: bitcoin-development@lists.sourceforge.net
Subject: [Bitcoin-development] Time
Date: Fri, 25 Jul 2014 02:14:20 +0100	[thread overview]
Message-ID: <53D1AF6C.7010802@gmail.com> (raw)


-----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
oo4MIdmp6vz984GWToyyLcLSEDT60UE9Hhe+U9RyF5J9kwbN8Uy4ozUHhFVP/0EL
q4O1V6ggPbHWgH4q8m8E9qWOlIFXCDgCjxpL8Ptxsk+UlBq2NWMiwTz6Tbc9KOB4
hOffzXCZV+DkwjFZD2Rc4rHaxw1yLuYr7DzmzwZbhRQclv9tZt9hoVaAT+RQpE1k
X7pi+zVzeMMng0bzUv8t/G+gq0gaelyV41MJQRparEXhnuYkgU7rAPKIQEG8qpc=
=T5fw
-----END PGP SIGNATURE-----




             reply	other threads:[~2014-07-25  1:14 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-07-25  1:14 Ron OHara [this message]
2014-07-25  1:41 ` [Bitcoin-development] Time Jeff Garzik
2014-07-25  2:35 ` Aaron Voisine
2014-07-25  2:39   ` Gregory Maxwell
2014-07-25  3:21     ` William Yager
2014-07-25  5:56       ` Aaron Voisine
2014-07-25 10:26         ` Mike Hearn
2014-07-25 14:45           ` Aaron Voisine
2014-07-25 16:03             ` Mike Hearn
2014-07-25 16:22               ` Natanael
2014-07-25 18:14                 ` Aaron Voisine
2014-07-25 10:30 ` Mike Hearn
2014-07-27 22:22   ` Peter Todd
2014-07-28 17:33   ` Troy Benjegerdes

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=53D1AF6C.7010802@gmail.com \
    --to=ron.ohara54@gmail.com \
    --cc=bitcoin-development@lists.sourceforge.net \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox