Return-Path: Received: from smtp1.osuosl.org (smtp1.osuosl.org [IPv6:2605:bc80:3010::138]) by lists.linuxfoundation.org (Postfix) with ESMTP id 03C0AC000B for ; Sun, 6 Mar 2022 20:54:08 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id D30EB81428 for ; Sun, 6 Mar 2022 20:54:07 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org X-Spam-Flag: NO X-Spam-Score: -1.897 X-Spam-Level: X-Spam-Status: No, score=-1.897 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_NONE=0.001] autolearn=ham autolearn_force=no Authentication-Results: smtp1.osuosl.org (amavisd-new); dkim=pass (2048-bit key) header.d=suredbits-com.20210112.gappssmtp.com Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id sikh-NJ-qoQ8 for ; Sun, 6 Mar 2022 20:54:07 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.8.0 Received: from mail-qv1-xf2f.google.com (mail-qv1-xf2f.google.com [IPv6:2607:f8b0:4864:20::f2f]) by smtp1.osuosl.org (Postfix) with ESMTPS id D623F81425 for ; Sun, 6 Mar 2022 20:54:06 +0000 (UTC) Received: by mail-qv1-xf2f.google.com with SMTP id j5so10662238qvs.13 for ; Sun, 06 Mar 2022 12:54:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suredbits-com.20210112.gappssmtp.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=B50l6rtbOXLS53rIwVtndROySrEgrIZpVE52sKt2ntI=; b=32BdhXGPSJGvNweYAVtc22Dk3n/Eo3Ffsr5MwRd8qpZus1AycBvzzY+4Fdh/Nosgro 4cUAt+W+kJOyDSFPsyBQAhwwRU5jt6JcmY5K84qmU/akuIiZYPOUS+mBuf+WIucJZRFu 9jYZ9dLjO478FNjyT0TpnHoOjI2vQby4A66qJjy1OslJx2dFELpJU0f32jchhFklvEP/ N025yyeTpuyRNpIYt75wfVocWzRaFNTe3Yr+Cko+jufPcN6frTJskjeaMVImWqElUE1F Ie7cN6abdvBY5HIZuSgVaEArZJdfLpx3I/nlDdLECjImnvUxGcEOG3KT5txSs+ErFtIx 2eJA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=B50l6rtbOXLS53rIwVtndROySrEgrIZpVE52sKt2ntI=; b=LvbtclWCy20f7+K98WbpEIzCCVmoJkKvYrkQRMrLfvzJwS5b7EcrMCTIS3m3sTI72o Pa9+Kc/rtGnxf+lz1AqNnShpVoMkIv1SpDFLNgJ+tZAjdPtNvI2LJpw9c9NY5aFH9cHt qlZuR4a8xzLNawcneiXjkdvGh4Yb5rRTc+8w+d/8GWhzZffMrxcqiXhuaTvIxvxiiSbn V0fifQgErpP9EJrvljowPQg/Ekm1d+cOFOrDJOYUqNJACN6NKRX1XaqJm2HExyaWxM42 dlNKcbGicUEF9juKgwCbYbRou4MB5ngci5ECe7xF+p33gdI4KfzXhgZaH2XG8yF9sDl6 3rXw== X-Gm-Message-State: AOAM533H6VMGqaj4O00IETEsZNtvJxo1U9tvIpU5PeUs4zW+dlrwcNhT YUMKu6g/Zv3JytXgU1gaZj4ZGL2hEV/zmZ3UO/5hvA== X-Google-Smtp-Source: ABdhPJz/s0VNsdONfYRvAl6KJTbJa4MlBc6bMauURhktw+7HOtwNK119roojeqetKJ4ErJjOxXBGSY6jmkscCsghsNA= X-Received: by 2002:a05:6214:242c:b0:432:b613:bb24 with SMTP id gy12-20020a056214242c00b00432b613bb24mr6263438qvb.29.1646600045727; Sun, 06 Mar 2022 12:54:05 -0800 (PST) MIME-Version: 1.0 References: <1ICs_kG6Eloiy6E4yLUkdFUI4EqKtaRPqcIY5kOM8Pq1xdWQHAMsMUxFsQ0xw2RcdMoMfxJSmlhb_ilXaw_nESliKxlE_Xp5tchQxXKD58E=@protonmail.com> <9yZl_Q0jy6DTD0BLoU-AaGZzHGO53238vIS8t54lGqFa0Rkk6-omZrTvwP3Rq4Yl3mp0krPPANseVFHebvLFw2-wj1FwPJxFSQPYrX6ujv0=@protonmail.com> In-Reply-To: <9yZl_Q0jy6DTD0BLoU-AaGZzHGO53238vIS8t54lGqFa0Rkk6-omZrTvwP3Rq4Yl3mp0krPPANseVFHebvLFw2-wj1FwPJxFSQPYrX6ujv0=@protonmail.com> From: Chris Stewart Date: Sun, 6 Mar 2022 14:53:55 -0600 Message-ID: To: ZmnSCPxj Content-Type: multipart/alternative; boundary="000000000000d0242405d992f215" X-Mailman-Approved-At: Sun, 06 Mar 2022 20:54:44 +0000 Cc: Bitcoin Protocol Discussion , "dlc-dev@mailmanlists.org" Subject: Re: [bitcoin-dev] Recurring bitcoin/LN payments using DLCs 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: Sun, 06 Mar 2022 20:54:08 -0000 --000000000000d0242405d992f215 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable FWIW, the initial use case that I hinted at in the OP is for lightning. The problem this company has is they offer an inbound liquidity service, but it is common after a user purchases liquidity, the channel goes unused. This is bad for the company as their liquidity is tied up in unproductive channels. The idea was to implement a monthly service fee that requires the user to pay a fixed amount if the channel isn=E2=80=99t being used. This compensates the company for the case where their liquidity is NOT being used. With standard lightning fees, you only get paid when liquidity is used. You don=E2=80=99t get paid when it is NOT being used. If you are offe= ring liquidity as a service this is bad. The user purchasing liquidity can make the choice to pay the liquidity fee, or not to pay it. In the case where a user does not pay the fee, the company can take this as a signal that they are no longer interested in the service. That way they can put their liquidity to use somewhere else that is more productive for the rest of the network. So it=E2=80=99s sort of a recurring payment for liquidity as a service, at = least that is how I=E2=80=99m thinking about it currently. On Sun, Mar 6, 2022 at 2:11 PM ZmnSCPxj wrote: > Good morning Chris, > > > >On the other hand, the above, where the oracle determines *when* the > fund can be spent, can also be implemented by a simple 2-of-3, and called > an "escrow". > > > > I think something that is underappreciated by protocol developers is th= e > fact that multisig requires interactiveness at settlement time. The > multisig escrow provider needs to know the exact details about the bitcoi= n > transaction and needs to issue a signature (gotta sign the outpoints, the > fee, the payout addresses etc). > > > > With PTLCs that isn't the case, and thus gives a UX improvement for > Alice & Bob that are using the escrow provider. The oracle (or escrow) ju= st > issues attestations. Bob or Alice take those attestations and complete th= e > adaptor signature. Instead of a bi-directional communication requirement > (the oracle working with Bob or Alice to build the bitcoin tx) at > settlement time there is only unidirectional communication required. > Non-interactive settlement is one of the big selling points of DLC style > applications IMO. > > > > One of the unfortunate things about LN is the interactiveness > requirements are very high, which makes developing applications hard > (especially mobile applications). I don't think this solves lightning's > problems, but it is a worthy goal to reduce interactiveness requirements > with new bitcoin applications to give better UX. > > Good point. > > I should note that 2-of-3 contracts are *not* transportable over LN, but > PTLCs *are* transportable. > So the idea still has merit for LN, as a replacement for 2-fo-3 escrows. > > Regards, > ZmnSCPxj > --000000000000d0242405d992f215 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
FWIW, the initial use case that I hinted at in the OP is = for lightning.

The probl= em this company has is they offer an inbound liquidity service, but it is c= ommon after a user purchases liquidity, the channel goes unused.

This is bad for the company as the= ir liquidity is tied up in unproductive channels. The idea was to implement= a monthly service fee that requires the user to pay a fixed amount if the = channel isn=E2=80=99t being used. This compensates the company for the case= where their liquidity is NOT being used. With standard lightning fees, you= only get paid when liquidity is used. You don=E2=80=99t get paid when it i= s NOT being used. If you are offering liquidity as a service this is bad.

The user purchasing liqui= dity can make the choice to pay the liquidity fee, or not to pay it. In the= case where a user does not pay the fee, the company can take this as a sig= nal that they are no longer interested in the service. That way they can pu= t their liquidity to use somewhere else that is more productive for the res= t of the network.

So it= =E2=80=99s sort of a recurring payment for liquidity as a service, at least= that is how I=E2=80=99m thinking about it currently.=C2=A0

<= div class=3D"gmail_quote">
On Sun, Mar= 6, 2022 at 2:11 PM ZmnSCPxj <ZmnSCPxj@protonmail.com> wrote:
Good morn= ing Chris,

> >On the other hand, the above, where the oracle determines *when* t= he fund can be spent, can also be implemented by a simple 2-of-3, and calle= d an "escrow".
>
> I think something that is underappreciated by protocol developers is t= he fact that multisig requires interactiveness at settlement time. The mult= isig escrow provider needs to know the exact details about the bitcoin tran= saction and needs to issue a signature (gotta sign the outpoints, the fee, = the payout addresses etc).
>
> With PTLCs that isn't the case, and thus gives a UX improvement fo= r Alice & Bob that are using the escrow provider. The oracle (or escrow= ) just issues attestations. Bob or Alice take those attestations and comple= te the adaptor signature. Instead of a bi-directional communication require= ment (the oracle working with Bob or Alice to build the bitcoin tx) at sett= lement time there is only unidirectional communication required. Non-intera= ctive settlement is one of the big selling points of DLC style applications= IMO.
>
> One of the unfortunate things about LN is the interactiveness requirem= ents are very high, which makes developing applications hard (especially mo= bile applications). I don't think this solves lightning's problems,= but it is a worthy goal to reduce interactiveness requirements with new bi= tcoin applications to give better UX.

Good point.

I should note that 2-of-3 contracts are *not* transportable over LN, but PT= LCs *are* transportable.
So the idea still has merit for LN, as a replacement for 2-fo-3 escrows.
Regards,
ZmnSCPxj
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