From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 9E5B8D0A for ; Fri, 24 May 2019 08:15:53 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from sender-of-o53.zoho.com (sender-of-o53.zoho.com [135.84.80.218]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id A15BDF4 for ; Fri, 24 May 2019 08:15:51 +0000 (UTC) ARC-Seal: i=1; a=rsa-sha256; t=1558685749; cv=none; d=zoho.com; s=zohoarc; b=cA4vxUqUcAcvtcfVnxs+o4VneANiBboA8q1o1/IZFsV5OKgZAhblVD8LQ9h2UDoxUEb3ZFSg1WEzwQNqueLbCYd5T/V7WUzyeEDXMN2qxvFbQGbCYCTGudDdvExnBj0Q4xeP7XsuDr48taCbtirQTushjikNX+1dBfPGw1KDq0I= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1558685749; h=Content-Type:Content-Transfer-Encoding:Date:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:To:ARC-Authentication-Results; bh=S7tIr5Bf33Y7PqcEo88UeYmYe7HtuDA1frInj6l8ous=; b=I0Xsq1VMV/d/NDIj0d0vuVTWHIjEVX1yjNBG5k1/0hYdXZELAc01JlOXNtgAnc+SAjMpMjRSlTrrPkaNm6BVezUMGdNjyCxo9W/hDBnySL59lxU87obCwwOd526lrMBr3xZ3h7ACO6twL6FYlfLHQLChzKqw61fuEry6m+vM/Og= ARC-Authentication-Results: i=1; mx.zoho.com; dkim=pass header.i=xbt.hk; spf=pass smtp.mailfrom=jl2012@xbt.hk; dmarc=pass header.from= header.from= Received: from [192.168.1.2] (1-64-133-115.static.netvigator.com [1.64.133.115]) by mx.zohomail.com with SMTPS id 1558685748775305.6786937343502; Fri, 24 May 2019 01:15:48 -0700 (PDT) From: Johnson Lau Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Mime-Version: 1.0 (Mac OS X Mail 12.4 \(3445.104.11\)) Date: Fri, 24 May 2019 16:15:45 +0800 References: <42F53D61-BAAE-464F-BB0D-4D0CDC554D9A@gmail.com> To: Tamas Blummer , bitcoin-dev In-Reply-To: <42F53D61-BAAE-464F-BB0D-4D0CDC554D9A@gmail.com> Message-Id: <21B03A11-EED7-423B-B885-9A963E86A708@xbt.hk> X-Mailer: Apple Mail (2.3445.104.11) X-ZohoMailClient: External X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org X-Mailman-Approved-At: Fri, 24 May 2019 14:39:19 +0000 Subject: Re: [bitcoin-dev] OP_DIFFICULTY to enable difficulty hedges (bets) without an oracle and 3rd party. X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Protocol Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 24 May 2019 08:15:53 -0000 A gamble like this, decentralised or not, is easy to manipulate since = difficulty is determined entirely by the last block in a cycle > On 24 May 2019, at 1:42 AM, Tamas Blummer via bitcoin-dev = wrote: >=20 > Difficulty change has profound impact on miner=E2=80=99s production = thereby introduce the biggest risk while considering an investment. > Commodity markets offer futures and options to hedge risks on = traditional trading venues. Some might soon list difficulty futures. >=20 > I think we could do much better than them natively within Bitcoin. >=20 > A better solution could be a transaction that uses nLocktime = denominated in block height, such that it is valid after the difficulty = adjusted block in the future. > A new OP_DIFFICULTY opcode would put onto stack the value of = difficulty for the block the transaction is included into.=20 > The output script may then decide comparing that value with a strike = which key can spend it.=20 > The input of the transaction would be a multi-sig escrow of those who = entered the bet.=20 > The winner would broadcast.=20 >=20 > Once signed by both the transaction would not carry any counterparty = risk and would not need an oracle to settle according to the bet. >=20 > I plan to draft a BIP for this as I think this opcode would serve = significant economic interest of Bitcoin economy, and is compatible with = Bitcoin=E2=80=99s aim not to introduce 3rd party to do so. >=20 > Do you see a fault in this proposal or want to contribute? >=20 > Tamas Blummer=20 >=20 > _______________________________________________ > bitcoin-dev mailing list > bitcoin-dev@lists.linuxfoundation.org > https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev