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From: Billy Tetrud <billy.tetrud@gmail.com>
Date: Sat, 26 Jun 2021 09:13:23 -0700
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To: Antoine Riard <antoine.riard@gmail.com>
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Subject: Re: [bitcoin-dev] Proposal: Full-RBF in Bitcoin Core 24.0
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>  services providers are offering zero-conf channels, where you can start
to spend instantly [0]. I believe that's an interesting usage

I agree those are interesting and useful cases. I suppose I should clarify
that when I asked if bitcoin should continue supporting 0-conf
transactions, I meant: should we make design decisions based on whether it
makes raw 0-conf transactions more or less difficult to double spend on? I
do think 0-conf transactions can be useful in situations where there is
some level of trust (either direct trust between the interacting parties,
or disperse trust that most people won't try to double spend, perhaps
because the transaction is small or their identity is tied to it). Fidelity
bonds sound like an interesting way to mitigate sybil attacks in a
reputation system.

On Thu, Jun 24, 2021 at 5:23 PM Antoine Riard <antoine.riard@gmail.com>
wrote:

> > Do we as a community want to support 0-conf payments in any way at this
> > point? It seems rather silly to make software design decisions to
> > accommodate 0-conf payments when there are better mechanisms for fast
> > payments (ie lightning).
>
> Well, we have zero-conf LN channels ? Actually, Lightning channel funding
> transactions should be buried under a few blocks, though few services
> providers are offering zero-conf channels, where you can start to spend
> instantly [0]. I believe that's an interesting usage, though IMHO as
> mentioned we can explore different security models to make 0-conf safe
> (reputation/fidelity-bond).
>
> > One question I have is: how does software generally inform the user abo=
ut
> 0-conf payment detection?
>
> Yes generally it's something like an "Unconfirmed" annotation on incoming
> txn, though at least this is what Blockstream Green or Electrum are doing=
.
>
> > But I
> suppose it would depend on how often 0-conf is used in the bitcoin
> ecosystem at this point, which I don't have any data on.
>
> There are few Bitcoin services well-known to rely on 0-conf. Beyond how
> much of the Bitcoin traffic is tied to a 0-conf is a hard question, a lot
> of 0-confs service providers are going to be reluctant to share the
> information, for a really good reason you will learn a subset of their
> business volumes.
>
> I'll see if I can come up with some Fermi estimation on this front.
>
> [0] https://www.bitrefill.com/thor-turbo-channels/
>
> Le mer. 16 juin 2021 =C3=A0 20:58, Billy Tetrud <billy.tetrud@gmail.com> =
a
> =C3=A9crit :
>
>> Russel O'Connor recently opined
>> <https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2021-June/01906=
1.html>
>> that RBF should be standard treatment of all transactions, rather than a=
s a
>> transaction opt-in/out. I agree with that. Any configuration in a
>> transaction that has not been committed into a block yet simply can't be
>> relied upon. Miners also have a clear incentive to ignore RBF rules and
>> mine anything that passes consensus. At best opting out of RBF is a weak
>> defense, and at worst it's simply a false sense of security that is like=
ly
>> to actively lead to theft events.
>>
>> Do we as a community want to support 0-conf payments in any way at this
>> point? It seems rather silly to make software design decisions to
>> accommodate 0-conf payments when there are better mechanisms for fast
>> payments (ie lightning).
>>
>> One question I have is: how does software generally inform the user abou=
t
>> 0-conf payment detection? Does software generally tell the user somethin=
g
>> along the lines of "This payment has not been finalized yet. All recipie=
nts
>> should wait until the transaction has at least 1 confirmation, and most
>> recipients should wait for 6 confirmations" ? I think unless we pressure
>> software to be very explicit about what counts as finality, users will
>> simply continue to do what they've always done. Rolling out this policy
>> change over the course of a year or two seems fine, no need to rush. But=
 I
>> suppose it would depend on how often 0-conf is used in the bitcoin
>> ecosystem at this point, which I don't have any data on.
>>
>> On Tue, Jun 15, 2021 at 10:00 AM Antoine Riard via bitcoin-dev <
>> bitcoin-dev@lists.linuxfoundation.org> wrote:
>>
>>> Hi,
>>>
>>> I'm writing to propose deprecation of opt-in RBF in favor of full-RBF a=
s
>>> the Bitcoin Core's default replacement policy in version 24.0. As a
>>> reminder, the next release is 22.0, aimed for August 1st, assuming
>>> agreement is reached, this policy change would enter into deployment ph=
ase
>>> a year from now.
>>>
>>> Even if this replacement policy has been deemed as highly controversial
>>> a few years ago, ongoing and anticipated changes in the Bitcoin ecosyst=
em
>>> are motivating this proposal.
>>>
>>> # RBF opt-out as a DoS Vector against Multi-Party Funded Transactions
>>>
>>> As explained in "On Mempool Funny Games against Multi-Party Funded
>>> Transactions'', 2nd issue [0], an attacker can easily DoS a multi-party
>>> funded transactions by propagating an RBF opt-out double-spend of its
>>> contributed input before the honest transaction is broadcasted by the
>>> protocol orchester. DoSes are qualified in the sense of either an attac=
ker
>>> wasting timevalue of victim's inputs or forcing exhaustion of the
>>> fee-bumping  reserve.
>>>
>>> This affects a series of Bitcoin protocols such as Coinjoin, onchain
>>> DLCs and dual-funded LN channels. As those protocols are still in the e=
arly
>>> phase of deployment, it doesn't seem to have been executed in the wild =
for
>>> now.  That said, considering that dual-funded are more efficient from a
>>> liquidity standpoint, we can expect them to be widely relied on, once
>>> Lightning enters in a more mature phase. At that point, it should becom=
e
>>> economically rational for liquidity service providers to launch those D=
oS
>>> attacks against their competitors to hijack user traffic.
>>>
>>> Beyond that, presence of those DoSes will complicate the design and
>>> deployment of multi-party Bitcoin protocols such as payment
>>> pools/multi-party channels. Note, Lightning Pool isn't affected as ther=
e is
>>> a preliminary stage where batch participants are locked-in their funds
>>> within an account witnessScript shared with the orchestrer.
>>>
>>> Of course, even assuming full-rbf, propagation of the multi-party funde=
d
>>> transactions can still be interfered with by an attacker, simply
>>> broadcasting a double-spend with a feerate equivalent to the honest
>>> transaction. However, it tightens the attack scenario to a scorched ear=
th
>>> approach, where the attacker has to commit equivalent fee-bumping reser=
ve
>>> to maintain the pinning and might lose the "competing" fees to miners.
>>>
>>> # RBF opt-out as a Mempools Partitions Vector
>>>
>>> A longer-term issue is the risk of mempools malicious partitions, where
>>> an attacker exploits network topology or divergence in mempools policie=
s to
>>> partition network mempools in different subsets. From then a wide range=
 of
>>> attacks can be envisioned such as package pinning [1], artificial
>>> congestion to provoke LN channels closure or manipulation of
>>> fee-estimator's feerate (the Core's one wouldn't be affected as it reli=
es
>>> on block confirmation, though other fee estimators designs deployed acr=
oss
>>> the ecosystem are likely going to be affected).
>>>
>>> Traditionally, mempools partitions have been gauged as a spontaneous
>>> outcome of a distributed systems like Bitcoin p2p network and I'm not a=
ware
>>> it has been studied in-depth for adversarial purposes. Though, deployme=
nt
>>> of second-layer
>>> protocols, heavily relying on sanity of a local mempool for
>>> fee-estimation and robust propagation of their time-sensitive transacti=
ons
>>> might lead to reconsider this position. Acknowledging this, RBF opt-out=
 is
>>> a low-cost partitioning tool, of which the existence nullifies most of
>>> potential progresses to mitigate malicious partitioning.
>>>
>>>
>>> To resume, opt-in RBF doesn't suit well deployment of robust
>>> second-layers protocol, even if those issues are still early and deserv=
e
>>> more research. At the same time, I believe a meaningful subset of the
>>> ecosystem  are still relying
>>> on 0-confs transactions, even if their security is relying on far weake=
r
>>> assumptions (opt-in RBF rule is a policy rule, not a consensus one) [2]=
 A
>>> rapid change of Core's mempool rules would be harming their quality of
>>> services and should be
>>> weighed carefully. On the other hand, it would be great to nudge them
>>> towards more secure handling of their 0-confs flows [3]
>>>
>>> Let's examine what could be deployed ecosystem-wise as enhancements to
>>> the 0-confs security model.
>>>
>>> # Proactive security models : Double-spend Monitoring/Receiver-side
>>> Fee-Topping with Package Relay
>>>
>>> From an attacker viewpoint, opt-in RBF isn't a big blocker to successfu=
l
>>> double-spends. Any motivated attacker can modify Core to mass-connect t=
o a
>>> wide portion of the network, announce txA to this subset, announce txA'=
 to
>>> the
>>> merchant. TxA' propagation will be encumbered by the privacy-preserving
>>> inventory timers (`OUTBOUND_INVENTORY_BROADCAST_INTERVAL`), of which an
>>> attacker has no care to respect.
>>>
>>> To detect a successful double-spend attempt, a Bitcoin service should
>>> run few full-nodes with well-spread connection graphs and unlinkable
>>> between them, to avoid being identified then maliciously partitioned fr=
om
>>> the rest of the network.
>>>
>>> I believe this tactic is already deployed by few Bitcoin services, and
>>> even one can throw flame at it because it over consumes network resourc=
es
>>> (bandwidth, connection slots, ...), it does procure a security advantag=
e to
>>> the ones doing it.
>>>
>>> One further improvement on top of this protection could be to react
>>> after the double-spend detection by attaching a CPFP to the merchant
>>> transaction, with a higher package feerate than the double-spend. Expec=
ted
>>> deployment of package-relay as a p2p mechanism/mempool policy in Bitcoi=
n
>>> Core should enable it to do so.
>>>
>>> # Reactive security models : EconomicReputation-based Compensations
>>>
>>> Another approach could be to react after the fact if a double-spend has
>>> been qualified. If the sender is already known to the service provider,=
 the
>>> service account can be slashed.  If the sender is a low-trusted
>>> counterparty to the merchant, "side-trust" models could be relied on. F=
or
>>> e.g a LN pubkey with a stacked reputation from your autopilot, LSATs, s=
take
>>> certificates, a HTLC-as-a-fidelity-bond, ... The space is quite wide th=
ere
>>> but I foresee those trust-minimized, decentralized solutions being adop=
ted
>>> by the LN ecosystem to patch the risks when you enter in a channel/HTLC
>>> operation with an anonymous counterparty.
>>>
>>> What other cool new tools could be considered to enhance 0-confs
>>> security ?
>>>
>>> To conclude, let's avoid replaying the contentious threads of a few
>>> years ago. What this new thread highlights is the fact that a transacti=
on
>>> relay/mempool acceptance policy might be beneficial to some class of
>>> already-deployed
>>> Bitcoin applications while being detrimental to newer ones. How do we
>>> preserve the current interests of 0-confs users while enabling upcoming
>>> interests of fancy L2s to flourish is a good conversation to have. I th=
ink.
>>>
>>> If there is ecosystem agreement on switching to full-RBF, but 0.24
>>> sounds too early, let's defer it to 0.25 or 0.26. I don't think Core ha=
s a
>>> consistent deprecation process w.r.t to policy rules heavily relied-on =
by
>>> Bitcoin users, if we do so let sets a precedent satisfying as many folk=
s as
>>> we can.
>>>
>>> Cheers,
>>> Antoine
>>>
>>> [0]
>>> https://lists.linuxfoundation.org/pipermail/lightning-dev/2021-May/0030=
33.html
>>>
>>> [1] See scenario 3 :
>>> https://lists.linuxfoundation.org/pipermail/lightning-dev/2020-June/002=
758.html
>>>
>>> [2] https://github.com/bitcoin/bitcoin/pull/10823#issuecomment-46648512=
1
>>>
>>> [3] And the LN ecosystem does have an interest to fix zero-confs
>>> security, if "turbo-channels"-like become normalized for mobile nodes
>>> _______________________________________________
>>> bitcoin-dev mailing list
>>> bitcoin-dev@lists.linuxfoundation.org
>>> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>>>
>>

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<div dir=3D"ltr">&gt;=C2=A0

services providers are offering zero-conf channels, where you can start to =
spend instantly [0]. I believe that&#39;s an interesting usage<div><br></di=
v><div>I agree those are interesting and useful cases. I suppose I should c=
larify that when I asked if bitcoin should continue supporting 0-conf trans=
actions, I meant: should we make design decisions based on whether it makes=
 raw 0-conf transactions more or less difficult to double spend on? I do th=
ink 0-conf transactions=C2=A0can be useful in situations where there is som=
e level of trust (either direct trust between the interacting parties, or d=
isperse trust that most people won&#39;t try to double spend, perhaps becau=
se the transaction is small or their identity is tied to it). Fidelity bond=
s sound like an interesting way to mitigate=C2=A0sybil attacks in a reputat=
ion system.</div></div><br><div class=3D"gmail_quote"><div dir=3D"ltr" clas=
s=3D"gmail_attr">On Thu, Jun 24, 2021 at 5:23 PM Antoine Riard &lt;<a href=
=3D"mailto:antoine.riard@gmail.com">antoine.riard@gmail.com</a>&gt; wrote:<=
br></div><blockquote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8e=
x;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir=3D"ltr"=
>&gt; Do we as a community want to support 0-conf payments in any way at th=
is<br>&gt; point? It seems rather silly to make software design decisions t=
o<br>&gt; accommodate 0-conf payments when there are better mechanisms for =
fast<br>&gt; payments (ie lightning).<br><br>Well, we have zero-conf LN cha=
nnels ? Actually, Lightning channel funding transactions should be buried u=
nder a few blocks, though few services providers are offering zero-conf cha=
nnels, where you can start to spend instantly [0]. I believe that&#39;s an =
interesting usage, though IMHO as mentioned we can explore different securi=
ty models to make 0-conf safe (reputation/fidelity-bond).<br><br>&gt; One q=
uestion I have is: how does software generally inform the user about<br>0-c=
onf payment detection?<br><br>Yes generally it&#39;s something like an &quo=
t;Unconfirmed&quot; annotation on incoming txn, though at least this is wha=
t Blockstream Green or Electrum are doing.<br><br>&gt; But I<br>suppose it =
would depend on how often 0-conf is used in the bitcoin<br>ecosystem at thi=
s point, which I don&#39;t have any data on.<br><br>There are few Bitcoin s=
ervices well-known to rely on 0-conf. Beyond how much of the Bitcoin traffi=
c is tied to a 0-conf is a hard question, a lot of 0-confs service provider=
s are going to be reluctant to share the information, for a really good rea=
son you will learn a subset of their business volumes.<br><br>I&#39;ll see =
if I can come up with some Fermi estimation on this front.<br><br>[0] <a hr=
ef=3D"https://www.bitrefill.com/thor-turbo-channels/" target=3D"_blank">htt=
ps://www.bitrefill.com/thor-turbo-channels/</a><br></div><br><div class=3D"=
gmail_quote"><div dir=3D"ltr" class=3D"gmail_attr">Le=C2=A0mer. 16 juin 202=
1 =C3=A0=C2=A020:58, Billy Tetrud &lt;<a href=3D"mailto:billy.tetrud@gmail.=
com" target=3D"_blank">billy.tetrud@gmail.com</a>&gt; a =C3=A9crit=C2=A0:<b=
r></div><blockquote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex=
;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir=3D"ltr">=
Russel O&#39;Connor <a href=3D"https://lists.linuxfoundation.org/pipermail/=
bitcoin-dev/2021-June/019061.html" target=3D"_blank">recently opined</a> th=
at RBF should=C2=A0be standard treatment of all transactions, rather than a=
s a transaction opt-in/out. I agree with that. Any configuration in a trans=
action that has not been committed into a block yet simply can&#39;t be rel=
ied upon. Miners also have a clear incentive to ignore RBF rules and mine a=
nything that passes consensus. At best opting out of RBF is a weak defense,=
 and at worst it&#39;s simply a false sense of security that is likely to a=
ctively=C2=A0lead to theft events.=C2=A0<br><div><br></div><div>Do we as a =
community want to support 0-conf payments in any way at this point? It seem=
s rather silly=C2=A0to make software design decisions to accommodate=C2=A00=
-conf payments when there are better mechanisms for fast payments (ie light=
ning).=C2=A0</div><div><br></div><div>One question I have is: how does soft=
ware generally inform the user about 0-conf payment detection? Does softwar=
e generally tell the user something along the lines of &quot;This payment h=
as not been finalized yet. All recipients should wait until the transaction=
 has at least 1 confirmation, and most recipients should wait for 6 confirm=
ations&quot; ? I think unless we pressure software to be very explicit abou=
t what counts as finality, users will simply continue to do what they&#39;v=
e always done. Rolling out this policy change over the course of a year or =
two seems fine, no need to rush. But I suppose it would depend on how often=
 0-conf is used in the bitcoin ecosystem at this point, which I don&#39;t h=
ave any data on.=C2=A0</div></div><br><div class=3D"gmail_quote"><div dir=
=3D"ltr" class=3D"gmail_attr">On Tue, Jun 15, 2021 at 10:00 AM Antoine Riar=
d via bitcoin-dev &lt;<a href=3D"mailto:bitcoin-dev@lists.linuxfoundation.o=
rg" target=3D"_blank">bitcoin-dev@lists.linuxfoundation.org</a>&gt; wrote:<=
br></div><blockquote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8e=
x;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir=3D"ltr"=
><div>Hi,<br><br>I&#39;m writing to propose deprecation of opt-in RBF in fa=
vor of full-RBF as the Bitcoin Core&#39;s default replacement policy in ver=
sion 24.0. As a reminder, the next release is 22.0, aimed for August 1st, a=
ssuming agreement is reached, this policy change would enter into deploymen=
t phase a year from now. <br><br>Even if this replacement policy has been d=
eemed as highly controversial a few years ago, ongoing and anticipated chan=
ges in the Bitcoin ecosystem are motivating this proposal.<br><br># RBF opt=
-out as a DoS Vector against Multi-Party Funded Transactions<br><br>As expl=
ained in &quot;On Mempool Funny Games against Multi-Party Funded Transactio=
ns&#39;&#39;, 2nd issue [0], an attacker can easily DoS a multi-party funde=
d transactions by propagating an RBF opt-out double-spend of its contribute=
d input before the honest transaction is broadcasted by the protocol orches=
ter. DoSes are qualified in the sense of either an attacker wasting timeval=
ue of victim&#39;s inputs or forcing exhaustion of the fee-bumping =C2=A0re=
serve.<br><br>This affects a series of Bitcoin protocols such as Coinjoin, =
onchain DLCs and dual-funded LN channels. As those protocols are still in t=
he early phase of deployment, it doesn&#39;t seem to have been executed in =
the wild for now.=C2=A0 That said, considering that dual-funded are more ef=
ficient from a liquidity standpoint, we can expect them to be widely relied=
 on, once Lightning enters in a more mature phase. At that point, it should=
 become economically rational for liquidity service providers to launch tho=
se DoS attacks against their competitors to hijack user traffic.<br><br>Bey=
ond that, presence of those DoSes will complicate the design and deployment=
 of multi-party Bitcoin protocols such as payment pools/multi-party channel=
s. Note, Lightning Pool isn&#39;t affected as there is a preliminary stage =
where batch participants are locked-in their funds within an account witnes=
sScript shared with the orchestrer.<br><br>Of course, even assuming full-rb=
f, propagation of the multi-party funded transactions can still be interfer=
ed with by an attacker, simply broadcasting a double-spend with a feerate e=
quivalent to the honest transaction. However, it tightens the attack scenar=
io to a scorched earth approach, where the attacker has to commit equivalen=
t fee-bumping reserve to maintain the pinning and might lose the &quot;comp=
eting&quot; fees to miners.<br><br># RBF opt-out as a Mempools Partitions V=
ector<br><br>A longer-term issue is the risk of mempools malicious partitio=
ns, where an attacker exploits network topology or divergence in mempools p=
olicies to partition network mempools in different subsets. From then a wid=
e range of attacks can be envisioned such as package pinning [1], artificia=
l congestion to provoke LN channels closure or manipulation of fee-estimato=
r&#39;s feerate (the Core&#39;s one wouldn&#39;t be affected as it relies o=
n block confirmation, though other fee estimators designs deployed across t=
he ecosystem are likely going to be affected).<br><br>Traditionally, mempoo=
ls partitions have been gauged as a spontaneous outcome of a distributed sy=
stems like Bitcoin p2p network and I&#39;m not aware it has been studied in=
-depth for adversarial purposes. Though, deployment of second-layer<br>prot=
ocols, heavily relying on sanity of a local mempool for fee-estimation and =
robust propagation of their time-sensitive transactions might lead to recon=
sider this position. Acknowledging this, RBF opt-out is a low-cost partitio=
ning tool, of which the existence nullifies most of potential progresses to=
 mitigate malicious partitioning.<br><br><br>To resume, opt-in RBF doesn&#3=
9;t suit well deployment of robust second-layers protocol, even if those is=
sues are still early and deserve more research. At the same time, I believe=
 a meaningful subset of the ecosystem =C2=A0are still relying<br>on 0-confs=
 transactions, even if their security is relying on far weaker assumptions =
(opt-in RBF rule is a policy rule, not a consensus one) [2] A rapid change =
of Core&#39;s mempool rules would be harming their quality of services and =
should be<br>weighed carefully. On the other hand, it would be great to nud=
ge them towards more secure handling of their 0-confs flows [3]<br><br>Let&=
#39;s examine what could be deployed ecosystem-wise as enhancements to the =
0-confs security model.<br><br># Proactive security models : Double-spend M=
onitoring/Receiver-side Fee-Topping with Package Relay<br><br>From an attac=
ker viewpoint, opt-in RBF isn&#39;t a big blocker to successful double-spen=
ds. Any motivated attacker can modify Core to mass-connect to a wide portio=
n of the network, announce txA to this subset, announce txA&#39; to the<br>=
merchant. TxA&#39; propagation will be encumbered by the privacy-preserving=
 inventory timers (`OUTBOUND_INVENTORY_BROADCAST_INTERVAL`), of which an at=
tacker has no care to respect.<br><br>To detect a successful double-spend a=
ttempt, a Bitcoin service should run few full-nodes with well-spread connec=
tion graphs and unlinkable between them, to avoid being identified then mal=
iciously partitioned from the rest of the network.<br><br>I believe this ta=
ctic is already deployed by few Bitcoin services, and even one can throw fl=
ame at it because it over consumes network resources (bandwidth, connection=
 slots, ...), it does procure a security advantage to the ones doing it.<br=
><br>One further improvement on top of this protection could be to react af=
ter the double-spend detection by attaching a CPFP to the merchant transact=
ion, with a higher package feerate than the double-spend. Expected deployme=
nt of package-relay as a p2p mechanism/mempool policy in Bitcoin Core shoul=
d enable it to do so.<br><br># Reactive security models : EconomicReputatio=
n-based Compensations<br><br>Another approach could be to react after the f=
act if a double-spend has been qualified. If the sender is already known to=
 the service provider, the service account can be slashed.=C2=A0 If the sen=
der is a low-trusted counterparty to the merchant, &quot;side-trust&quot; m=
odels could be relied on. For e.g a LN pubkey with a stacked reputation fro=
m your autopilot, LSATs, stake certificates, a HTLC-as-a-fidelity-bond, ...=
 The space is quite wide there but I foresee those trust-minimized, decentr=
alized solutions being adopted by the LN ecosystem to patch the risks when =
you enter in a channel/HTLC operation with an anonymous counterparty. <br><=
br></div><div>What other cool new tools could be considered to enhance 0-co=
nfs security ?<br></div><div><br>To conclude, let&#39;s avoid replaying the=
 contentious threads of a few years ago. What this new thread highlights is=
 the fact that a transaction relay/mempool acceptance policy might be benef=
icial to some class of already-deployed <br>Bitcoin applications while bein=
g detrimental to newer ones. How do we preserve the current interests of 0-=
confs users while enabling upcoming interests of fancy L2s to flourish is a=
 good conversation to have. I think.<br><br>If there is ecosystem agreement=
 on switching to full-RBF, but 0.24 sounds too early, let&#39;s defer it to=
 0.25 or 0.26. I don&#39;t think Core has a consistent deprecation process =
w.r.t to policy rules heavily relied-on by Bitcoin users, if we do so let s=
ets a precedent satisfying as many folks as we can.<br><br>Cheers,<br>Antoi=
ne<br><br>[0] <a href=3D"https://lists.linuxfoundation.org/pipermail/lightn=
ing-dev/2021-May/003033.html" target=3D"_blank">https://lists.linuxfoundati=
on.org/pipermail/lightning-dev/2021-May/003033.html</a><br><br>[1] See scen=
ario 3 : <a href=3D"https://lists.linuxfoundation.org/pipermail/lightning-d=
ev/2020-June/002758.html" target=3D"_blank">https://lists.linuxfoundation.o=
rg/pipermail/lightning-dev/2020-June/002758.html</a><br><br>[2] <a href=3D"=
https://github.com/bitcoin/bitcoin/pull/10823#issuecomment-466485121" targe=
t=3D"_blank">https://github.com/bitcoin/bitcoin/pull/10823#issuecomment-466=
485121</a><br><br></div>[3] And the LN ecosystem does have an interest to f=
ix zero-confs security, if &quot;turbo-channels&quot;-like become normalize=
d for mobile nodes<br></div>
_______________________________________________<br>
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bitcoin-dev@lists.linuxfoundation.org</a><br>
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rel=3D"noreferrer" target=3D"_blank">https://lists.linuxfoundation.org/mail=
man/listinfo/bitcoin-dev</a><br>
</blockquote></div>
</blockquote></div>
</blockquote></div>

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