From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp4.osuosl.org (smtp4.osuosl.org [IPv6:2605:bc80:3010::137]) by lists.linuxfoundation.org (Postfix) with ESMTP id 2BB6BC000B for ; Fri, 18 Feb 2022 14:48:46 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id 13FFC41BA2 for ; Fri, 18 Feb 2022 14:48:46 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org X-Spam-Flag: NO X-Spam-Score: -1.599 X-Spam-Level: X-Spam-Status: No, score=-1.599 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, FROM_LOCAL_NOVOWEL=0.5, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001] autolearn=ham autolearn_force=no Authentication-Results: smtp4.osuosl.org (amavisd-new); dkim=pass (2048-bit key) header.d=protonmail.com Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id auhdwH4YTogM for ; Fri, 18 Feb 2022 14:48:44 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 Received: from mail-4324.protonmail.ch (mail-4324.protonmail.ch [185.70.43.24]) by smtp4.osuosl.org (Postfix) with ESMTPS id 944F341B39 for ; Fri, 18 Feb 2022 14:48:44 +0000 (UTC) Date: Fri, 18 Feb 2022 14:48:38 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=protonmail.com; s=protonmail3; t=1645195720; bh=aeZHPGRh1IGiyMwid9eQf/HTIZhuYe3fowRmtgxOV7o=; h=Date:To:From:Cc:Reply-To:Subject:Message-ID:In-Reply-To: References:From:To:Cc:Date:Subject:Reply-To:Feedback-ID: Message-ID; b=JxWEX3KGSbm1bRLFkhE6iE+Vn7cfWJNr6vaDait/WnG+VJv68XYABx695q/RjiqFM ePXIjaXoJM6JhQCTP8PxkxwT0WubL38zCVBQvKCQeTU31G74CWCHKfOxXOTw6tFWIE lEc7qw0Zlfw6kLB1JIejoeHoFUC/kZEO06kxjUFCb033q0R1GAFLGhZMvqO0B7WzSf UXQELSZv8Fw2nI6Bx4kgEVfTp38hse71jtUDPUjwXMLHYIhk4WdF4mEtN/W3xunLYM C0oKjUQYCKGT/X+0NoG9QbgYyYbkuGsGR6pcKjHwE89TW/scaTq9913XaJG5V5G3R5 JbJhA0aPnoIDA== To: Erik Aronesty From: ZmnSCPxj Reply-To: ZmnSCPxj Message-ID: In-Reply-To: References: <6nZ-SkxvJLrOCOIdUtLOsdnl94DoX_NHY0uwZ7sw78t24FQ33QJlJU95W7Sk1ja5EFic5a3yql14MLmSAYFZvLGBS4lDUJfr8ut9hdB7GD4=@protonmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Cc: Bitcoin Protocol Discussion , Anthony Towns Subject: Re: [bitcoin-dev] `OP_EVICT`: An Alternative to `OP_TAPLEAFUPDATEVERIFY` 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, 18 Feb 2022 14:48:46 -0000 Good morning Erik, > hey, i read that whole thing, but i'm confused as to why it's necessary > > seems like N of N participants can pre-sign an on-chain transfer of funds= for each participant to a new address that consists of (N-1) or (N-1) part= icipants, of which each portion of the signature is encrypted for the same = (N-1) participants > > then any (N-1) subset of participants can collude publish that transactio= n at any time to remove any other member from=C2=A0the pool > > all of the set up=C2=A0 (dkg for N-1), and transfer (encryption of partia= l sigs) is done offchain, and online with the participants=C2=A0that are on= line As I understand your counterproposal, it would require publishing one trans= action per evicted participant. In addition, each participant has to store `N!` possible orderings in which= participants can be evicted, as you cannot predict the future and cannot p= redict which partiicpants will go offline first. Finally, please see also the other thread on lightning-dev: https://lists.l= inuxfoundation.org/pipermail/lightning-dev/2022-February/003479.html In this thread, I point out that if we ever use channel factories, it would= be best if we treat each channel as a 2-of-2 that participates in an overa= ll N-of-N (i.e. the N in the outer channel factory is composed of 2-of-2). For example, instead of the channel factory being signed by participants `A= `, `B`, `C`, `D`, instead the channel factory is signed by `AB`, `AC`, `AD`= , `BC`, `BD`, `CD`, so that if e.g. participant B needs to be evicted, we c= an evict the signers `AB`, `BC`, and `BD`. This means that for the channel factory case, already the number of "partic= ipants" is quadratic on the number of *actual* participants, which greatly = increases the number of transactions that need to be evicted in one-evictio= n-at-a-time schemes (which is how I understand your proposal) as well as in= creasing the `N!` number of signatures that need to be exchanged during set= up. But yes, certainly that can work, just as pre-signed transactions can be us= ed instead of `OP_CTV` or pretty much any non-`OP_CHECKMULTISIG` opcode, xr= ef Smart Contracts Unchained. Regards, ZmnSCPxj