Return-Path: Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) by lists.linuxfoundation.org (Postfix) with ESMTP id E0EAAC0171 for ; Fri, 31 Jan 2020 21:02:34 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id D3DBB86CD7 for ; Fri, 31 Jan 2020 21:02:34 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from hemlock.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id mL-iiEK4nmnn for ; Fri, 31 Jan 2020 21:02:33 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from newmail.dtrt.org (li1228-87.members.linode.com [45.79.129.87]) by hemlock.osuosl.org (Postfix) with ESMTPS id 9228D86416 for ; Fri, 31 Jan 2020 21:02:33 +0000 (UTC) Received: from harding by newmail.dtrt.org with local (Exim 4.92) (envelope-from ) id 1ixdQt-00076g-UX; Fri, 31 Jan 2020 16:02:31 -0500 Date: Fri, 31 Jan 2020 15:01:29 -0600 From: "David A. Harding" To: ZmnSCPxj , Bitcoin Protocol Discussion Message-ID: <20200131210129.ufnjxb2x7wllhcuw@ganymede> References: <2U3WdMgyM7iLhQnak0GjkH6u6C0C_Ry59WucTiRthajkOXqAirvN55U39to0kQY5bDzv9SBZXy5Qbx2QZopJwktHqVUKbfpCjEfq1H_v0vE=@protonmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="gscbx64t2zhk4gwn" Content-Disposition: inline In-Reply-To: <2U3WdMgyM7iLhQnak0GjkH6u6C0C_Ry59WucTiRthajkOXqAirvN55U39to0kQY5bDzv9SBZXy5Qbx2QZopJwktHqVUKbfpCjEfq1H_v0vE=@protonmail.com> User-Agent: NeoMutt/20180716 Subject: Re: [bitcoin-dev] Onchain fee insurance mechanism X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Bitcoin Protocol Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 31 Jan 2020 21:02:35 -0000 --gscbx64t2zhk4gwn Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Jan 31, 2020 at 03:42:08AM +0000, ZmnSCPxj via bitcoin-dev wrote: > Let me then propose a specific mechanism for feerate insurance against on= chain feerate spikes. >=20 > [...] >=20 > At current blockheight B, Alice and Ingrid then arrange a series of trans= actions: >=20 > nLockTime: B+1 > nSequence: RBF enabled, no relative locktime. > inputs: Alice 5000000, Ingrid 800000 > outputs: > Bob 400000 > Alice 99400 > Ingrid 800400 > fee: 200 > > [...] Ingrid is able to rescind this series of pre-signed transactions at any time before one of the transactions is confirmed by double spending her UTXO (e.g. via a RBF fee bump). If Alice needs to trust Ingrid to honor the contract anyway, they might as well not include Ingrid's input or output in the transaction and instead use an external accounting and payment mechanism. For example, Alice and Ingrid agree to a fee schedule: > height: B+1 > fee: 200 > > height: B+2 > fee: 400 > > height: B+3 > fee: 599 > > height: B+4 > fee: 3600 Then they wait for whichever version of the transaction to confirm and one of them remits to the other the appropriate amount (either 400, 200, or 1 base unit to Ingrid, or 3,000 base units to Alice). This remittance can be done by whatever mechanism they both support (e.g. an onchain transaction, an LN payment, or just credit on an exchange). Since it's possible to achieve equivilent security (or lack thereof) without the locktime mechanism, I don't think the locktime mechanism adds anything to the idea of hedging fees---and, as you note, it suffers =66rom incompatibility with some cases where users would be especially eager to obtain feerate insurance. -Dave --gscbx64t2zhk4gwn Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCgAdFiEEgxUkqkMp0LnoXjCr2dtBqWwiadMFAl40lakACgkQ2dtBqWwi adOaoxAAnVbJme1HN9kl+rY2V0Arxf7oSXlACBNO04rBrMnW4q5Ne7WVQYHI+RV4 zs+lOIzayQ+7bOa3QJ7EfWTODOc8VlykWCMOpF3Ry4GFgWpbhhS2F/CWBcG9bW09 NS4TIu7qEDqUWJV64sZ63kmo5pp8Mv86/1uKl0oGdK/yW36D5hMa1WnkSocFwOM8 L2r947WFhJk5BE1L6BST2bHm6uYP/wK1YVaBBrK5/9SR01TZA+XcduhUG6SPGChy RBlwkXh1/fXOrrur4WyqJROHzyJdK7kfFPcQPDdgJDGh5c9rG6WwpbJ2C3aF2ZFJ DNokeYsWxiOSxDaQP2KdMHKXroWTnW3y+TXaiDsjjtuJI9VOJjcEfM9eQaEszykz XvqF4MaorgA0m+kPYXdsipVYQQvBuVd2apfIQ/1NvMaJpo15PPBELOo3oecwH2+d YHp1CjRCfCZlGujDi+gjOvRHxQP3Y9I1UIj9c9+pf0lpgjxa0QGNR/DfqHakjuVD NmOi3ueNdiwMDrmUE8rIwj2MRKo/oNrGgwXLl0A2/PhDHgGmlOmOd3NDJwLmumsl 3nIE6OEUb6rfFA7wlx85MIOZ7AmVVAFOgD8925oFwCtQi33yxouuSAHfbt41ytp6 vOguZ9EMRQGtqB1tVl9+Iq23BDz2DrYegFi7JZt0FllyUr+H0ds= =qDn5 -----END PGP SIGNATURE----- --gscbx64t2zhk4gwn--