Return-Path: Received: from smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id BA900C000D for ; Tue, 21 Sep 2021 02:11:56 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id AAD3940333 for ; Tue, 21 Sep 2021 02:11:56 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org X-Spam-Flag: NO X-Spam-Score: 1.099 X-Spam-Level: * X-Spam-Status: No, score=1.099 tagged_above=-999 required=5 tests=[BAYES_50=0.8, 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, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001] autolearn=unavailable autolearn_force=no Authentication-Results: smtp4.osuosl.org (amavisd-new); dkim=pass (1024-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 dI45qLhffYn3 for ; Tue, 21 Sep 2021 02:11:53 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 Received: from mail4.protonmail.ch (mail4.protonmail.ch [185.70.40.27]) by smtp4.osuosl.org (Postfix) with ESMTPS id 73B6F40330 for ; Tue, 21 Sep 2021 02:11:53 +0000 (UTC) Date: Tue, 21 Sep 2021 02:11:42 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=protonmail.com; s=protonmail; t=1632190310; bh=YcWLYwU1MgvCIGiOpFuggt09qWVNasrRJJdc7gOcxCA=; h=Date:To:From:Cc:Reply-To:Subject:In-Reply-To:References:From; b=I+yng9UnKZC8Em80tkybb2n9C/y0fWjUkGAh6UozlBdcLgjRMjbyFXcPTVRKObCjR R01l9XA/C/XopKYrYNwzOk+P1Mdlr48ezc5tL/Bqjndln4EMBEAmOobKupGmtnDFFx JiyHwd9S6ssoq/x4DTLZ24Thh7E2sD7L0xtREYy4= To: Jeremy From: ZmnSCPxj Reply-To: ZmnSCPxj Message-ID: In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Cc: Bitcoin development mailing list , lightning-dev Subject: Re: [bitcoin-dev] [Lightning-dev] Inherited IDs - A safer, more powerful alternative to BIP-118 (ANYPREVOUT) for scaling Bitcoin 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: Tue, 21 Sep 2021 02:11:56 -0000 Good morning John Law, > (at the expense of requiring an on-chain transaction to update > the set of channels created by the factory). Hmmm this kind of loses the point of a factory? By my understanding, the point is that the set of channels can be changed *= without* an onchain transaction. Otherwise, it seems to me that factories with this "expense of requiring an= on-chain transaction" can be created, today, without even Taproot: * The funding transaction output pays to a simple n-of-n. * The above n-of-n is spent by an *offchain* transaction that splits the fu= nds to the current set of channels. * To change the set of channels, the participants perform this ritual: * Create, but do not sign, an alternate transaction that spends the above= n-of-n to a new n-of-n with the same participants (possibly with tweaked k= eys). * Create and sign, but do not broadcast, a transaction that spends the ab= ove alternate n-of-n output and splits it to the new set of channels. * Sign the alternate transaction and broadcast it, this is the on-chain t= ransaction needed to update the set of channels. The above works today without changes to Bitcoin, and even without Taproot = (though for large N the witness size does become fairly large without Tapro= ot). The above is really just a "no updates" factory that cuts through its closi= ng transaction with the opening of a new factory. Regards, ZmnSCPxj