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From: Johnson Lau <jl2012@xbt.hk>
To: Matthew Roberts <matthew@roberts.pm>,
	bitcoin-dev <bitcoin-dev@lists.linuxfoundation.org>
Subject: Re: [bitcoin-dev] BIP: OP_PRANDOM
Date: Fri, 20 May 2016 13:34:03 +0200	[thread overview]
Message-ID: <CBBB62CD-2E30-4C9F-962E-3F340B29EDA7@xbt.hk> (raw)
In-Reply-To: <CAAEDBiEB_RXBjrLB8kDb52bJOwZK-arVeHA_9LyoDgAraLKHNg@mail.gmail.com>

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Using the hash of multiple blocks does not make it any safer. The miner of the last block always determines the results, by knowing the hashes of all previous blocks.

> 
> == Security
> Pay-to-script-hash can be used to protect the details of contracts that use OP_PRANDOM from the prying eyes of miners. However, since there is also a non-zero risk that a participant in a contract may attempt to bribe a miner the inclusion of multiple block hashes as a source of randomness is a must. Every miner would effectively need to be bribed to ensure control over the results of the random numbers, which is already very unlikely. The risk approaches zero as N goes up.


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  reply	other threads:[~2016-05-20 11:34 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-05-20 10:57 [bitcoin-dev] BIP: OP_PRANDOM Matthew Roberts
2016-05-20 11:34 ` Johnson Lau [this message]
2016-05-20 14:30   ` James MacWhyte
2016-05-20 15:05   ` Matthew Roberts
2016-05-20 18:32     ` Eric Martindale
2016-05-22 13:30       ` Jeremy
2016-05-24 14:30         ` Sergio Demian Lerner
2016-05-24 14:36           ` Sergio Demian Lerner

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