From: Gregory Maxwell <gmaxwell@gmail•com>
To: Matt Whitlock <bip@mattwhitlock•name>
Cc: Bitcoin Development <bitcoin-development@lists•sourceforge.net>,
Flavien Charlon <flavien.charlon@coinprism•com>
Subject: Re: [Bitcoin-development] [BIP draft] CHECKLOCKTIMEVERIFY - Prevent a txout from being spent until an expiration time
Date: Fri, 3 Oct 2014 09:17:48 -0700 [thread overview]
Message-ID: <CAAS2fgT5VSQywp_5_N2JboVT-LQDZ76UQXBvwZ4KfdQ06jAPig@mail.gmail.com> (raw)
In-Reply-To: <1987325.zKPNeYyO8K@crushinator>
On Fri, Oct 3, 2014 at 7:28 AM, Matt Whitlock <bip@mattwhitlock•name> wrote:
> Is there a reason why we can't have the new opcode simply replace the top stack item with the block height of the txout being redeemed?
This would not be soft-forking compatible.
It also would be unsafe in that it would result in transactions which
once mined could not be restored in a reorg through no fault of the
participants, which makes the coins less fungible and differently safe
to accept. It risks creating weird pressures around immediate block
admission since a one additional block delay could forever censor such
a transaction (E.g. increases the power of single miners to censor or
steal). Avoiding this is a conscious decision in Bitcoin and also part
of the justification for the 100 block maturity of newly generated
coins.
It also would require violating the script/transaction/block layering
more substantially, complicating implementations, and making the
validity of a script no longer a deterministic pure function of the
transaction.
Avoiding these issues is a conscious design in OP_CHECKLOCKTIMEVERIFY.
I would strenuously oppose a proposal which failed in any of these
respects.
> Then arbitrary logic could be implemented, including "output cannot be spent until a certain time" and also "output can ONLY be spent until a certain time," as well as complex logic with alternative key groups with differing time constraints.
You can already achieve the not spendable after logic with a
cancellation spend that moves the coin in the usual way. (Which
doesn't even require the participant be online, with the help of some
network service to queue unlocked transactions).
> OP_CHECKLOCKTIMEVERIFY, as conceived, seems too limited, IMHO.
It is intentionally so, and yet it covers the intended use cases;
including ones with alternative key groups, they are just not
exclusive.
next prev parent reply other threads:[~2014-10-03 16:17 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-10-01 13:08 Peter Todd
2014-10-01 15:01 ` Gavin Andresen
2014-10-02 1:06 ` Peter Todd
2014-10-01 15:29 ` Sergio Lerner
2014-10-01 17:06 ` Peter Todd
2014-10-01 18:23 ` Luke Dashjr
2014-10-01 20:58 ` Gavin Andresen
2014-10-01 21:04 ` Alan Reiner
2014-10-01 21:34 ` Gavin Andresen
2014-10-02 0:12 ` Peter Todd
2014-10-02 0:05 ` Peter Todd
2014-10-02 0:55 ` Luke Dashjr
2014-10-02 1:09 ` Peter Todd
2014-10-02 15:05 ` Flavien Charlon
2014-10-03 14:28 ` Matt Whitlock
2014-10-03 14:30 ` Matt Whitlock
2014-10-03 16:17 ` Gregory Maxwell [this message]
2014-10-03 17:50 ` Luke Dashjr
2014-10-03 20:58 ` Mike Hearn
2014-10-03 23:12 ` Jeff Garzik
2014-10-04 0:38 ` Peter Todd
2014-10-04 12:58 ` Mike Hearn
2014-10-07 15:50 ` Gavin Andresen
2014-10-07 16:08 ` Mike Hearn
2014-10-08 10:26 ` Wladimir
2014-10-09 3:13 ` Alan Reiner
2014-10-09 6:14 ` Adam Back
2014-10-09 6:28 ` Gregory Maxwell
2014-10-09 6:33 ` Peter Todd
2014-10-09 6:40 ` Gregory Maxwell
2014-10-08 4:07 ` Tom Harding
2014-10-08 10:15 ` Mike Hearn
2015-03-16 22:22 ` [Bitcoin-development] Relative CHECKLOCKTIMEVERIFY (was CLTV proposal) Matt Corallo
2015-03-19 17:39 ` Zooko Wilcox-OHearn
2015-04-21 7:59 ` Peter Todd
2015-04-26 11:35 ` Jorge Timón
2015-04-26 12:20 ` Jorge Timón
2015-04-27 19:35 ` Peter Todd
2015-04-28 7:44 ` Jorge Timón
2015-05-04 2:15 ` Matt Corallo
2015-05-04 11:24 ` Jorge Timón
2015-05-05 0:41 ` Btc Drak
2015-05-05 19:19 ` Jorge Timón
2015-05-05 20:38 ` Tier Nolan
2015-05-06 7:37 ` Jorge Timón
2015-05-06 22:09 ` Tier Nolan
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