path: root/6d/a1082dbdf41b09189a0c9c7cd90d7ee3d0cee2

Return-Path: <runchao.han@monash.edu>
Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org
	[172.17.192.35])
	by mail.linuxfoundation.org (Postfix) with ESMTPS id 0CF91C2C
	for <bitcoin-dev@lists.linuxfoundation.org>;
	Mon, 12 Aug 2019 10:02:42 +0000 (UTC)
X-Greylist: whitelisted by SQLgrey-1.7.6
Received: from mail-pf1-f181.google.com (mail-pf1-f181.google.com
	[209.85.210.181])
	by smtp1.linuxfoundation.org (Postfix) with ESMTPS id A909987D
	for <bitcoin-dev@lists.linuxfoundation.org>;
	Mon, 12 Aug 2019 10:02:40 +0000 (UTC)
Received: by mail-pf1-f181.google.com with SMTP id q139so1155643pfc.13
	for <bitcoin-dev@lists.linuxfoundation.org>;
	Mon, 12 Aug 2019 03:02:40 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=monash.edu; s=google;
	h=from:message-id:mime-version:subject:date:in-reply-to:cc:to
	:references; bh=4QYhHUG0OuebgFZtEAKkjU0Ibqh2Gp6JLlfWXCKed+g=;
	b=SrCKH/DL92h3VD4xWPKhb1IP1OdaXlyvlVZLnkfYIy1jGxTuoHitb1e/hSGST9USTH
	w4kEa8NVexU4kkrHTd/dfbBh5CDzPNRsMGI968q1eRdpcznTow7ZlKVaRgzE/xeL1J2G
	UpJ5i9YIyD6fB2P7jBN6w526TId0xN2JltCeFYkktO0yJoFbjX3ObRV/MYHMoiOuLUnh
	YrtwIR2Zupcnu7lAhjo2no+MyszOiE3+6IBJr86mxifeHydK3wf0GYbrYTODRQxOjK3T
	fTe6oJix4OZw5MW2wwypYfC7isEnGwEYXwulitvl0tWlKFuYu1fL3u0Svn7ST3Jfbz47
	aoqA==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
	d=1e100.net; s=20161025;
	h=x-gm-message-state:from:message-id:mime-version:subject:date
	:in-reply-to:cc:to:references;
	bh=4QYhHUG0OuebgFZtEAKkjU0Ibqh2Gp6JLlfWXCKed+g=;
	b=KZZiU2SMGAuIDfsNJ0Xl4oVJIcj4yJab3rWDA4Q0dKd824c9E4JRyIhsYRd0TEJX7t
	3qrCWSp/UxCE7HjSs+IKv/lbk/R8+wxEyxK+bOYXvYEI7vh8o6RbMm2UZz9mh7nZH23n
	plt2OuHJQ/MIJCrjpYfK/MwOEU8v6SJoDiyKRnS4emdhJnPbi0pl1UtVovLHqCaVnDdP
	SC4CX+tmnpKKfutf7hoCdgMWT7qmfHbVj2GhOdwCr+zsW9YwyzR6rVInvcaLCGRwo7Pr
	PUdddpDNaiE08sHje5L7DJdtUroPDFRXa9RMq0jKtXsj2Bl1mvSxdsFBat2FmnDX2Apj
	t0nA==
X-Gm-Message-State: APjAAAWx9owi4t4ci9cQXbG1YIuZkGc6VmrLH0lcqiZhFgv0c/2Md6Ry
	LNxB9d8mKvCGrClCszxY5gB/Sg==
X-Google-Smtp-Source: APXvYqy5VIJfEw24maD5gdNuhFWqALDqvX4cLA3vJ1ExpK3qAWg6AZ8ljEFs9X3EeoaJk0Z/ypcAVA==
X-Received: by 2002:a17:90a:3be5:: with SMTP id
	e92mr2634306pjc.86.1565604160138; 
	Mon, 12 Aug 2019 03:02:40 -0700 (PDT)
Received: from [10.0.0.4] ([149.167.146.137]) by smtp.gmail.com with ESMTPSA id
	v145sm8884374pfc.31.2019.08.12.03.02.36
	(version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128);
	Mon, 12 Aug 2019 03:02:39 -0700 (PDT)
From: Runchao Han <runchao.han@monash.edu>
Message-Id: <419535C8-DE1D-425B-A38C-4196607E43D3@monash.edu>
Content-Type: multipart/alternative;
	boundary="Apple-Mail=_24A2BD3F-7E81-463A-8647-9155232E151D"
Mime-Version: 1.0 (Mac OS X Mail 12.4 \(3445.104.11\))
Date: Mon, 12 Aug 2019 20:02:33 +1000
In-Reply-To: <OLQmXBBI4kc9mkjbpr92bKp3UFhmg7ZtTn-m_VNinXNDT4CYz9Jf45gpSfxmkzXQLJfchMk7AaqEjbEor-ZJ02xrd_0yb2MOekXfRyovj6U=@protonmail.com>
To: ZmnSCPxj <ZmnSCPxj@protonmail.com>
References: <CAEtgg6GOdceubg+b=-MvH66CKGBy-67mbQR01JpG3L1YJ1jaVw@mail.gmail.com>
	<qBFyALsLsiKkSXsssc3T7dvwrXtzBXmAAmTFWAt04AkrFwbWnoCdGIjoyqMZGnJa5Y4CX5mi0-1uWtuzPT5Swr3txw6NthtkOUdzCOlyfXo=@protonmail.com>
	<ADA03200-1EED-4EAD-B320-3F2034F00954@monash.edu>
	<aJ7usJIj2_reg-36SKEUDRApK8AhsIm2esl-I1CJSxs8cZACAmuR0X1bBNDK_zlDOUlzUWD2n2pCnbYx20Jg8kvAyryKZ9mqe0OH2J0QivY=@protonmail.com>
	<CABnocSBSKsmWeRCOZE6DHwPXc2rucQGkHvjd+wJ+9JAJOT5=QQ@mail.gmail.com>
	<212E8AD5-0EED-468E-8AFC-134611514CBC@monash.edu>
	<OLQmXBBI4kc9mkjbpr92bKp3UFhmg7ZtTn-m_VNinXNDT4CYz9Jf45gpSfxmkzXQLJfchMk7AaqEjbEor-ZJ02xrd_0yb2MOekXfRyovj6U=@protonmail.com>
X-Mailer: Apple Mail (2.3445.104.11)
X-Spam-Status: No, score=-2.0 required=5.0 tests=BAYES_00,DKIM_SIGNED,
	DKIM_VALID, DKIM_VALID_AU, HTML_MESSAGE,
	RCVD_IN_DNSWL_NONE 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: Tue, 13 Aug 2019 02:14:06 +0000
Cc: Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>,
	"jiangshan.yu@monash.edu" <jiangshan.yu@monash.edu>
Subject: Re: [bitcoin-dev] OP_LOOKUP_OUTPUT proposal
X-BeenThere: bitcoin-dev@lists.linuxfoundation.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: Bitcoin Protocol Discussion <bitcoin-dev.lists.linuxfoundation.org>
List-Unsubscribe: <https://lists.linuxfoundation.org/mailman/options/bitcoin-dev>,
	<mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=unsubscribe>
List-Archive: <http://lists.linuxfoundation.org/pipermail/bitcoin-dev/>
List-Post: <mailto:bitcoin-dev@lists.linuxfoundation.org>
List-Help: <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=help>
List-Subscribe: <https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev>,
	<mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=subscribe>
X-List-Received-Date: Mon, 12 Aug 2019 10:02:42 -0000


--Apple-Mail=_24A2BD3F-7E81-463A-8647-9155232E151D
Content-Transfer-Encoding: quoted-printable
Content-Type: text/plain;
	charset=utf-8

Hi ZmnSCPxj,

Thanks for your explanation. It=E2=80=99s comprehensive.

I think our disagreement is on the step 6.
In step 6,

- Alice can publish or withhold the WJT tx
- Bob can wait or unilaterally close the WJT payment channel

I see the following things:

First, both Alice and Bob can do something on the WJT blockchain at this =
stage. What will happen if they publish txs simultaneously?
For example, Alice publishes WJT tx while Bob publishes the tx closing =
the channel.

Second, will the concurrent txs introduce some attacks?  I guess =
concurrent-while-conflicting txs lead to highly unpredictable =
behaviours.
For example, Alice or Bob uses high tx fee to bribe miners to accept =
her/his tx, in order to gain some advantage on the concurrent txs?
Also, the =E2=80=9Cwhale transaction=E2=80=9D works here. Will this =
introduce some double-spending variants?

Third, assume Bob doesn=E2=80=99t wait any more and closes the channel. =
In this case, Bob cannot get the premium.
This is not consistent with the original American Call Option, in which =
Bob should still get the premium.

To conclude, I find this protocol highly depends on the implementation =
of the payment channel as well as the expertise of participants (Alice =
and Bob) c.f. relatively low usability.
We may need a suitable payment channel implementation here. What=E2=80=99s=
 your opinion on the payment channel suitable for this scenario?

Sincerely,
Runchao

> On 12 Aug 2019, at 6:05 pm, ZmnSCPxj <ZmnSCPxj@protonmail.com> wrote:
>=20
> Good morning Runchao,
>=20
>=20
> Sent with ProtonMail Secure Email.
>=20
> =E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90 =
Original Message =E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=
=80=90
> On Monday, August 12, 2019 11:19 AM, Runchao Han =
<runchao.han@monash.edu <mailto:runchao.han@monash.edu>> wrote:
>=20
>> Good morning ZmnSCPxj,
>>=20
>> Sorry for the ambiguity of my last email. It was Sunday and I wrote =
it in 1 min on my bed. Let me elaborate what we are thinking of here.
>>=20
>> ## Analysis on the protocol from Fournier et al.
>>=20
>> In this protocol, Bob participates in the swap following the steps =
below:
>>=20
>> 1. Alice and Bob creates a payment channel on WJT blockchain.
>> 2. Bob creates the WJT transaction using the joint account of Alice =
and Bob, including 1) Bob's input of 1,000,000 WJT, 2) Alice=E2=80=99s =
input for the 10,000 WJT premium. This transaction should be signed by =
both Alice and Bob in order to be valid.
>> 3. Bob signs the WJT transaction and sends the WJT transaction to =
Alice.
>> 4. Alice signs this WJT transaction. At this stage, Alice has both =
the valid BTC transaction and the valid WJT transaction.
>> 5. Alice broadcasts both the BTC transaction and the WJT transaction.
>=20
> Incorrect.
>=20
> The order is below.
> I add also the behavior when the protocol is stalled such that a step =
is not completed.
>=20
> 1.  Alice broadcasts and confirms a BTC transaction paying an HTLC, =
hashlock Bob, Timelock Alice.
>    * Alice is initiating the protocol via this step, thus =
non-completion of this step is simply not performing the protocol.
> 2.  Alice informs the BTC transaction to Bob.
>    * If Alice does not perform this, Bob does not know it and Alice =
locked her own money for no reason.
> 3.  Alice and Bob indicate their inputs for the WJT-side funding =
transaction.
>    * If Alice does not perform this, it aborts the protocol and Alice =
locked her own money for no reason.
>    * If Bob does not perform this, it aborts the protocol and Bob =
turns down the opportunity to earn 10,000 WJT (opportunity cost).
> 4.  Alice and Bob exchange signatures for the WJT-side claim =
transaction which spends the funding transaction via the hashlock side =
and gives 1,000,000 WJT to payout to Alice and 10,000 WJT premium to =
Bob.
>    Order does not matter as funding  tx is still unsigned.
>    * If Alice does not perform this, it aborts the protocol and Alice =
locked her own money for no reason.
>    * If Bob does not perform this, it aborts the protocol and Bob =
turns down the opportunity to earn 10,000 WJT (opportunity cost).
> 5.  Bob provides signatures for the WJT funding tx,
>    * If Bob does not perform this, it aborts the protocol and Bob =
turns down the opportunity to earn 10,000 WJT (opportunity cost).
> 6.  Alice signs WJT funding tx and broacasts and confirms.
>    * If Alice does not perform this, Bob invalidates the transaction =
by spending any of his inputs.
>      * Alice has an option here, but a very short option: up until Bob =
grows tired of waiting.
>        Bob can make this timeout arbitrarily small, without requiring =
input from Alice.
>        What value would there be in a 1-second option, even gotten for =
free, when Alice has spent fees on the BTC-side transaction in the first =
place?
> 7.  Alice completes the claim transaction and broadcasts.
>    * If Alice does not perform this, Bob simply waits out the timelock =
and recovers his funds plus premium.
> 8.  Bob spends the BTC HTLC via the hashlock path.
>    * If Bob does not perform this, Bob has given money for free to =
Alice.
>=20
> Thus I do not believe this is needed for blockchain-layer atomic =
swaps.
>=20
> For Lightning-layer atomic swaps, the solution requires that two =
hashes be used on the WJT side, and is largely the above protocol in =
very broad strokes.
> Unfortunately, using two hashes instead of one leaks to intermediate =
hops that the payment involved a cross-currency swap, thus undesirable.
>=20
>=20
>=20
>>=20
>> In a word, Bob is responsible for preparing the WJT transaction, =
while Alice is responsible for preparing the BTC transaction and =
broadcasting both transactions.
>>=20
>> Here, if Bob stalls, nothing will happen, because Bob cannot spend =
the 10,000 WJT premium without Alice=E2=80=99s signature.
>> If Alice stalls, you are saying that Bob can spend the input of =
1,000,000 WJT so he does not lose any money.
>>=20
>> I have 3 questions on this scheme.
>>=20
>> First, I=E2=80=99m not sure how do you define =E2=80=9CAlice =
stalls=E2=80=9D. In this case, Alice can stall by 1) withhold the WJT =
tx, or 2) broadcast BTC/WJT funding txs but withhold the preimage.
>> If 2), this protocol is okay. But what about 1) i.e. Alice withholds =
the WJT tx? Here, Bob cannot do anything except for closing the payment =
channel and quit.
>=20
> Yes.
>=20
>>=20
>> Second, I=E2=80=99m not sure whether Bob can spend his money in this =
payment channel while the payment channel is still valid.
>> In Bitcoin, Bob needs to close the payment channel and get back his =
money first, then he can spend the money.
>=20
> Depends on how the payment channel is implemented.
> If you do something like send transactions spending the internal state =
outputs, then ratifying this later by performing a transaction =
cut-through to derive the next state update, then it is no different =
from blockchain layer.
> Of course, if you postulate the non-cooperation of Alice in this, =
there is indeed a need to close unilaterally.
> But this is the same as any non-cooperation in any channel system: =
that is the entire point why you have unilateral closes.
>=20
>>=20
>> Third, let=E2=80=99s optimistically assume Bob can close this payment =
channel without Alice=E2=80=99s consent.
>=20
> Every payment channel system worth consideration today has a =
unilateral close.
> There is no need for optimism.
>=20
>> Now he decides to close this channel if Alice does not broadcast the =
WJT tx all the time.
>> Alice does not need to pay for the premium if she withholds the WJT =
tx. If Alice decides not to proceed this swap, Bob should close this =
channel and get back 1,000,000 WJT. However, Bob cannot get the 10,000 =
WJT premium.
>=20
> And this time frame can be made arbitarily small by Bob by simple =
threat of unilateral close, thus not making it an option for Alice.
>=20
> Regards,
> ZmnSCPxj


--Apple-Mail=_24A2BD3F-7E81-463A-8647-9155232E151D
Content-Transfer-Encoding: quoted-printable
Content-Type: text/html;
	charset=utf-8

<html><head><meta http-equiv=3D"Content-Type" content=3D"text/html; =
charset=3Dutf-8"></head><body style=3D"word-wrap: break-word; =
-webkit-nbsp-mode: space; line-break: after-white-space;" class=3D"">Hi =
ZmnSCPxj,<div class=3D""><br class=3D""></div><div class=3D"">Thanks for =
your explanation. It=E2=80=99s comprehensive.</div><div class=3D""><br =
class=3D""></div><div class=3D"">I think our disagreement is on the step =
6.</div><div class=3D"">In step 6,</div><div class=3D""><br =
class=3D""></div><div class=3D"">- Alice can publish or withhold the WJT =
tx</div><div class=3D"">- Bob can wait or unilaterally close the WJT =
payment channel</div><div class=3D""><br class=3D""></div><div =
class=3D"">I see the following things:</div><div class=3D""><br =
class=3D""></div><div class=3D"">First, both Alice and Bob can do =
something on the WJT blockchain at this stage. What will happen if they =
publish txs simultaneously?</div><div class=3D"">For example, Alice =
publishes WJT tx while Bob publishes the tx closing the =
channel.</div><div class=3D""><br class=3D""></div><div class=3D"">Second,=
 will the concurrent txs introduce some attacks? &nbsp;I guess =
concurrent-while-conflicting txs lead to highly unpredictable =
behaviours.</div><div class=3D"">For example, Alice or Bob uses high tx =
fee to bribe miners to accept her/his tx, in order to gain some =
advantage on the concurrent txs?</div><div class=3D"">Also, the =E2=80=9Cw=
hale transaction=E2=80=9D works here. Will this introduce some =
double-spending variants?</div><div class=3D""><br class=3D""></div><div =
class=3D"">Third, assume Bob doesn=E2=80=99t wait any more and closes =
the channel. In this case, Bob cannot get the premium.</div><div =
class=3D"">This is not consistent with the original American Call =
Option, in which Bob should still get the premium.</div><div =
class=3D""><br class=3D""></div><div class=3D"">To conclude, I find this =
protocol highly depends on the implementation of the payment channel as =
well as the expertise of participants (Alice and Bob) c.f. relatively =
low usability.</div><div class=3D"">We may need a suitable payment =
channel implementation here. What=E2=80=99s your opinion on the payment =
channel suitable for this scenario?</div><div class=3D""><div><br =
class=3D""></div><div>Sincerely,</div><div>Runchao</div><div><br =
class=3D""><blockquote type=3D"cite" class=3D""><div class=3D"">On 12 =
Aug 2019, at 6:05 pm, ZmnSCPxj &lt;<a =
href=3D"mailto:ZmnSCPxj@protonmail.com" =
class=3D"">ZmnSCPxj@protonmail.com</a>&gt; wrote:</div><br =
class=3D"Apple-interchange-newline"><div class=3D""><span =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none; float: none; =
display: inline !important;" class=3D"">Good morning Runchao,</span><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><span =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none; float: none; =
display: inline !important;" class=3D"">Sent with ProtonMail Secure =
Email.</span><br style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none;" class=3D""><br style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none;" class=3D""><span style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none; float: none; display: inline !important;" =
class=3D"">=E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90=
 Original Message =E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=
=80=90</span><br style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none;" class=3D""><span style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none; float: none; display: inline !important;" class=3D"">On Monday, =
August 12, 2019 11:19 AM, Runchao Han &lt;</span><a =
href=3D"mailto:runchao.han@monash.edu" style=3D"font-family: Helvetica; =
font-size: 12px; font-style: normal; font-variant-caps: normal; =
font-weight: normal; letter-spacing: normal; orphans: auto; text-align: =
start; text-indent: 0px; text-transform: none; white-space: normal; =
widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; =
-webkit-text-stroke-width: 0px;" =
class=3D"">runchao.han@monash.edu</a><span style=3D"caret-color: rgb(0, =
0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none; float: none; display: inline !important;" =
class=3D"">&gt; wrote:</span><br style=3D"caret-color: rgb(0, 0, 0); =
font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D""><br style=3D"caret-color: rgb(0, 0, =
0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D""><blockquote type=3D"cite" =
style=3D"font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
orphans: auto; text-align: start; text-indent: 0px; text-transform: =
none; white-space: normal; widows: auto; word-spacing: 0px; =
-webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D"">Good morning ZmnSCPxj,<br =
class=3D""><br class=3D"">Sorry for the ambiguity of my last email. It =
was Sunday and I wrote it in 1 min on my bed. Let me elaborate what we =
are thinking of here.<br class=3D""><br class=3D"">## Analysis on the =
protocol from Fournier et al.<br class=3D""><br class=3D"">In this =
protocol, Bob participates in the swap following the steps below:<br =
class=3D""><br class=3D"">1. Alice and Bob creates a payment channel on =
WJT blockchain.<br class=3D"">2. Bob creates the WJT transaction using =
the joint account of Alice and Bob, including 1) Bob's input of =
1,000,000 WJT, 2) Alice=E2=80=99s input for the 10,000 WJT premium. This =
transaction should be signed by both Alice and Bob in order to be =
valid.<br class=3D"">3. Bob signs the WJT transaction and sends the WJT =
transaction to Alice.<br class=3D"">4. Alice signs this WJT transaction. =
At this stage, Alice has both the valid BTC transaction and the valid =
WJT transaction.<br class=3D"">5. Alice broadcasts both the BTC =
transaction and the WJT transaction.<br class=3D""></blockquote><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><span =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none; float: none; =
display: inline !important;" class=3D"">Incorrect.</span><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><span =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none; float: none; =
display: inline !important;" class=3D"">The order is below.</span><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><span =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none; float: none; =
display: inline !important;" class=3D"">I add also the behavior when the =
protocol is stalled such that a step is not completed.</span><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><span =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none; float: none; =
display: inline !important;" class=3D"">1. &nbsp;Alice broadcasts and =
confirms a BTC transaction paying an HTLC, hashlock Bob, Timelock =
Alice.</span><br style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none;" class=3D""><span style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none; float: none; display: inline !important;" =
class=3D"">&nbsp;&nbsp;&nbsp;* Alice is initiating the protocol via this =
step, thus non-completion of this step is simply not performing the =
protocol.</span><br style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none;" class=3D""><span style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none; float: none; display: inline !important;" class=3D"">2. =
&nbsp;Alice informs the BTC transaction to Bob.</span><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><span =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none; float: none; =
display: inline !important;" class=3D"">&nbsp;&nbsp;&nbsp;* If Alice =
does not perform this, Bob does not know it and Alice locked her own =
money for no reason.</span><br style=3D"caret-color: rgb(0, 0, 0); =
font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D""><span style=3D"caret-color: rgb(0, 0, =
0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none; float: none; display: inline !important;" =
class=3D"">3. &nbsp;Alice and Bob indicate their inputs for the WJT-side =
funding transaction.</span><br style=3D"caret-color: rgb(0, 0, 0); =
font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D""><span style=3D"caret-color: rgb(0, 0, =
0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none; float: none; display: inline !important;" =
class=3D"">&nbsp;&nbsp;&nbsp;* If Alice does not perform this, it aborts =
the protocol and Alice locked her own money for no reason.</span><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><span =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none; float: none; =
display: inline !important;" class=3D"">&nbsp;&nbsp;&nbsp;* If Bob does =
not perform this, it aborts the protocol and Bob turns down the =
opportunity to earn 10,000 WJT (opportunity cost).</span><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><span =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none; float: none; =
display: inline !important;" class=3D"">4. &nbsp;Alice and Bob exchange =
signatures for the WJT-side claim transaction which spends the funding =
transaction via the hashlock side and gives 1,000,000 WJT to payout to =
Alice and 10,000 WJT premium to Bob.</span><br style=3D"caret-color: =
rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: =
normal; font-variant-caps: normal; font-weight: normal; letter-spacing: =
normal; text-align: start; text-indent: 0px; text-transform: none; =
white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D""><span style=3D"caret-color: rgb(0, 0, =
0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none; float: none; display: inline !important;" =
class=3D"">&nbsp;&nbsp;&nbsp;Order does not matter as funding &nbsp;tx =
is still unsigned.</span><br style=3D"caret-color: rgb(0, 0, 0); =
font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D""><span style=3D"caret-color: rgb(0, 0, =
0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none; float: none; display: inline !important;" =
class=3D"">&nbsp;&nbsp;&nbsp;* If Alice does not perform this, it aborts =
the protocol and Alice locked her own money for no reason.</span><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><span =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none; float: none; =
display: inline !important;" class=3D"">&nbsp;&nbsp;&nbsp;* If Bob does =
not perform this, it aborts the protocol and Bob turns down the =
opportunity to earn 10,000 WJT (opportunity cost).</span><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><span =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none; float: none; =
display: inline !important;" class=3D"">5. &nbsp;Bob provides signatures =
for the WJT funding tx,</span><br style=3D"caret-color: rgb(0, 0, 0); =
font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D""><span style=3D"caret-color: rgb(0, 0, =
0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none; float: none; display: inline !important;" =
class=3D"">&nbsp;&nbsp;&nbsp;* If Bob does not perform this, it aborts =
the protocol and Bob turns down the opportunity to earn 10,000 WJT =
(opportunity cost).</span><br style=3D"caret-color: rgb(0, 0, 0); =
font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D""><span style=3D"caret-color: rgb(0, 0, =
0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none; float: none; display: inline !important;" =
class=3D"">6. &nbsp;Alice signs WJT funding tx and broacasts and =
confirms.</span><br style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none;" class=3D""><span style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none; float: none; display: inline !important;" =
class=3D"">&nbsp;&nbsp;&nbsp;* If Alice does not perform this, Bob =
invalidates the transaction by spending any of his inputs.</span><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><span =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none; float: none; =
display: inline !important;" class=3D"">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;* =
Alice has an option here, but a very short option: up until Bob grows =
tired of waiting.</span><br style=3D"caret-color: rgb(0, 0, 0); =
font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D""><span style=3D"caret-color: rgb(0, 0, =
0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none; float: none; display: inline !important;" =
class=3D"">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Bob can make this =
timeout arbitrarily small, without requiring input from Alice.</span><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><span =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none; float: none; =
display: inline !important;" =
class=3D"">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;What value would =
there be in a 1-second option, even gotten for free, when Alice has =
spent fees on the BTC-side transaction in the first place?</span><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><span =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none; float: none; =
display: inline !important;" class=3D"">7. &nbsp;Alice completes the =
claim transaction and broadcasts.</span><br style=3D"caret-color: rgb(0, =
0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D""><span style=3D"caret-color: rgb(0, 0, =
0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none; float: none; display: inline !important;" =
class=3D"">&nbsp;&nbsp;&nbsp;* If Alice does not perform this, Bob =
simply waits out the timelock and recovers his funds plus =
premium.</span><br style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none;" class=3D""><span style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none; float: none; display: inline !important;" class=3D"">8. &nbsp;Bob =
spends the BTC HTLC via the hashlock path.</span><br style=3D"caret-color:=
 rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: =
normal; font-variant-caps: normal; font-weight: normal; letter-spacing: =
normal; text-align: start; text-indent: 0px; text-transform: none; =
white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D""><span style=3D"caret-color: rgb(0, 0, =
0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none; float: none; display: inline !important;" =
class=3D"">&nbsp;&nbsp;&nbsp;* If Bob does not perform this, Bob has =
given money for free to Alice.</span><br style=3D"caret-color: rgb(0, 0, =
0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D""><br style=3D"caret-color: rgb(0, 0, =
0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D""><span style=3D"caret-color: rgb(0, 0, =
0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none; float: none; display: inline !important;" =
class=3D"">Thus I do not believe this is needed for blockchain-layer =
atomic swaps.</span><br style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none;" class=3D""><br style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none;" class=3D""><span style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none; float: none; display: inline !important;" class=3D"">For =
Lightning-layer atomic swaps, the solution requires that two hashes be =
used on the WJT side, and is largely the above protocol in very broad =
strokes.</span><br style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none;" class=3D""><span style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none; float: none; display: inline !important;" class=3D"">Unfortunately, =
using two hashes instead of one leaks to intermediate hops that the =
payment involved a cross-currency swap, thus undesirable.</span><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" =
class=3D""><blockquote type=3D"cite" style=3D"font-family: Helvetica; =
font-size: 12px; font-style: normal; font-variant-caps: normal; =
font-weight: normal; letter-spacing: normal; orphans: auto; text-align: =
start; text-indent: 0px; text-transform: none; white-space: normal; =
widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><br =
class=3D"">In a word, Bob is responsible for preparing the WJT =
transaction, while Alice is responsible for preparing the BTC =
transaction and broadcasting both transactions.<br class=3D""><br =
class=3D"">Here, if Bob stalls, nothing will happen, because Bob cannot =
spend the 10,000 WJT premium without Alice=E2=80=99s signature.<br =
class=3D"">If Alice stalls, you are saying that Bob can spend the input =
of 1,000,000 WJT so he does not lose any money.<br class=3D""><br =
class=3D"">I have 3 questions on this scheme.<br class=3D""><br =
class=3D"">First, I=E2=80=99m not sure how do you define =E2=80=9CAlice =
stalls=E2=80=9D. In this case, Alice can stall by 1) withhold the WJT =
tx, or 2) broadcast BTC/WJT funding txs but withhold the preimage.<br =
class=3D"">If 2), this protocol is okay. But what about 1) i.e. Alice =
withholds the WJT tx? Here, Bob cannot do anything except for closing =
the payment channel and quit.<br class=3D""></blockquote><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><span =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none; float: none; =
display: inline !important;" class=3D"">Yes.</span><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" =
class=3D""><blockquote type=3D"cite" style=3D"font-family: Helvetica; =
font-size: 12px; font-style: normal; font-variant-caps: normal; =
font-weight: normal; letter-spacing: normal; orphans: auto; text-align: =
start; text-indent: 0px; text-transform: none; white-space: normal; =
widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><br =
class=3D"">Second, I=E2=80=99m not sure whether Bob can spend his money =
in this payment channel while the payment channel is still valid.<br =
class=3D"">In Bitcoin, Bob needs to close the payment channel and get =
back his money first, then he can spend the money.<br =
class=3D""></blockquote><br style=3D"caret-color: rgb(0, 0, 0); =
font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D""><span style=3D"caret-color: rgb(0, 0, =
0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none; float: none; display: inline !important;" =
class=3D"">Depends on how the payment channel is implemented.</span><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><span =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none; float: none; =
display: inline !important;" class=3D"">If you do something like send =
transactions spending the internal state outputs, then ratifying this =
later by performing a transaction cut-through to derive the next state =
update, then it is no different from blockchain layer.</span><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><span =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none; float: none; =
display: inline !important;" class=3D"">Of course, if you postulate the =
non-cooperation of Alice in this, there is indeed a need to close =
unilaterally.</span><br style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none;" class=3D""><span style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none; float: none; display: inline !important;" class=3D"">But this is =
the same as any non-cooperation in any channel system: that is the =
entire point why you have unilateral closes.</span><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><br =
style=3D"caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: =
12px; font-style: normal; font-variant-caps: normal; font-weight: =
normal; letter-spacing: normal; text-align: start; text-indent: 0px; =
text-transform: none; white-space: normal; word-spacing: 0px; =
-webkit-text-stroke-width: 0px; text-decoration: none;" =
class=3D""><blockquote type=3D"cite" style=3D"font-family: Helvetica; =
font-size: 12px; font-style: normal; font-variant-caps: normal; =
font-weight: normal; letter-spacing: normal; orphans: auto; text-align: =
start; text-indent: 0px; text-transform: none; white-space: normal; =
widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; =
-webkit-text-stroke-width: 0px; text-decoration: none;" class=3D""><br =
class=3D"">Third, let=E2=80=99s optimistically assume Bob can close this =
payment channel without Alice=E2=80=99s consent.<br =
class=3D""></blockquote><br style=3D"caret-color: rgb(0, 0, 0); =
font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D""><span style=3D"caret-color: rgb(0, 0, =
0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none; float: none; display: inline !important;" =
class=3D"">Every payment channel system worth consideration today has a =
unilateral close.</span><br style=3D"caret-color: rgb(0, 0, 0); =
font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D""><span style=3D"caret-color: rgb(0, 0, =
0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none; float: none; display: inline !important;" =
class=3D"">There is no need for optimism.</span><br style=3D"caret-color: =
rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: =
normal; font-variant-caps: normal; font-weight: normal; letter-spacing: =
normal; text-align: start; text-indent: 0px; text-transform: none; =
white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D""><br style=3D"caret-color: rgb(0, 0, =
0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D""><blockquote type=3D"cite" =
style=3D"font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
orphans: auto; text-align: start; text-indent: 0px; text-transform: =
none; white-space: normal; widows: auto; word-spacing: 0px; =
-webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D"">Now he decides to close this channel =
if Alice does not broadcast the WJT tx all the time.<br class=3D"">Alice =
does not need to pay for the premium if she withholds the WJT tx. If =
Alice decides not to proceed this swap, Bob should close this channel =
and get back 1,000,000 WJT. However, Bob cannot get the 10,000 WJT =
premium.<br class=3D""></blockquote><br style=3D"caret-color: rgb(0, 0, =
0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D""><span style=3D"caret-color: rgb(0, 0, =
0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none; float: none; display: inline !important;" =
class=3D"">And this time frame can be made arbitarily small by Bob by =
simple threat of unilateral close, thus not making it an option for =
Alice.</span><br style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none;" class=3D""><br style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none;" class=3D""><span style=3D"caret-color: rgb(0, 0, 0); font-family: =
Helvetica; font-size: 12px; font-style: normal; font-variant-caps: =
normal; font-weight: normal; letter-spacing: normal; text-align: start; =
text-indent: 0px; text-transform: none; white-space: normal; =
word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: =
none; float: none; display: inline !important;" =
class=3D"">Regards,</span><br style=3D"caret-color: rgb(0, 0, 0); =
font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;" class=3D""><span style=3D"caret-color: rgb(0, 0, =
0); font-family: Helvetica; font-size: 12px; font-style: normal; =
font-variant-caps: normal; font-weight: normal; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none; float: none; display: inline !important;" =
class=3D"">ZmnSCPxj</span></div></blockquote></div><br =
class=3D""></div></body></html>=

--Apple-Mail=_24A2BD3F-7E81-463A-8647-9155232E151D--