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 24FDF941 for ; Sat, 22 Dec 2018 14:25:27 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mail-40133.protonmail.ch (mail-40133.protonmail.ch [185.70.40.133]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 5B8117C for ; Sat, 22 Dec 2018 14:25:26 +0000 (UTC) Date: Sat, 22 Dec 2018 14:25:16 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=protonmail.com; s=default; t=1545488724; bh=YdzfmBI0gswA1F2HoY8B+Bnc8n1YWbzz9Qgu0r67xXA=; h=Date:To:From:Cc:Reply-To:Subject:In-Reply-To:References: Feedback-ID:From; b=ms/54561ScRsb10EEasUburLK7isKLAz0LmjaPAhq4upNZBe1NcqYZxusUkLFVk3v K4WuN+6VJ9J0VIWXeFd9MlST3p6JyXHy23+2qAC3g9oYLQUr6tsc/MrhvDVzFxwbO7 P0fJAROTRWvoZ8vSkFzJzaSIXR28blkq42SGEfP4= To: Johnson Lau From: ZmnSCPxj Reply-To: ZmnSCPxj Message-ID: In-Reply-To: <34B38940-524D-42B9-8A67-6A62DCE04665@xbt.hk> References: <9F8C0789-48E9-448A-A239-DB4AFB902A00@xbt.hk> <8z5NQkaOUo9z-wdBphQtZrxIf7OCtVQFvK3neMWvcRsngld5XJs-vt7CLuY46ZOp_pX8gEd92pMdkEkp8CUOMH9lUTw5ocWsbDPiaKdSa2I=@protonmail.com> <34B38940-524D-42B9-8A67-6A62DCE04665@xbt.hk> Feedback-ID: el4j0RWPRERue64lIQeq9Y2FP-mdB86tFqjmrJyEPR9VAtMovPEo9tvgA0CrTsSHJeeyPXqnoAu6DN-R04uJUg==:Ext:ProtonMail MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-2.2 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FROM, FROM_LOCAL_NOVOWEL, RCVD_IN_DNSWL_LOW 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: Sun, 23 Dec 2018 18:43:54 +0000 Cc: bitcoin-dev Subject: Re: [bitcoin-dev] Safer NOINPUT with output tagging 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: Sat, 22 Dec 2018 14:25:27 -0000 Good morning Johnson, > Generally speaking, I think walletless protocol is needed only when you w= ant to rely a third party to open a offchain smart contract. It could be co= inswap, eltoo, or anything similar. I think a third party would be pointless in general, but then I am strongly= against custodiality. The idea is that you have some kind of hardware wallet or similar "somewhat= cold" storage *that you control yourself*, and crate channels for your hot= offchain Lightning wallet, without adding more transactions from your some= what-cold storage to your hot offchain Lightning wallet on the blockchain. Then you could feed a set of addresses to the hot offchain wallet (addresse= s your somewhat-cold storage controls) so that when channels are closed, th= e funds go to your somwhat-cold storage. I also doubt that any custodial service would want to mess around with dedu= cting funds from what the user input as the desired payment. I have not se= en a custodial service that does so (this is not a scientific study; I rare= ly use custodial services); custodial services will deduct more from your b= alance than what you send, but will not modify what you send, and will prev= ent you from sending more than your balance minus the fees they charge for = sending onchain. Even today, custodial services deducting from your sent value (rather than = the balance remaining after you send) would be problematic when interacting= with merchants (or their payment processors) accepting onchain payments; t= he merchant would refuse to service a lower value than what it charges and = it may be very technically difficult to recover such funds from the merchan= t. I expect such a custodial service would quickly lose users, but the world s= urprises me often. Regards, ZmnSCPxj