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Topic: The Lightning Network FAQ - page 51. (Read 32053 times)

legendary
Activity: 2898
Merit: 1823
November 19, 2020, 04:26:12 AM


In 2017, there was an article dedicated to this issue.
https://medium.com/@jonaldfyookball/mathematical-proof-that-the-lightning-network-cannot-be-a-decentralized-bitcoin-scaling-solution-1b8147650800

Unfortunately, it was ignored by the Bitcoin community. Partly because they couldn't understand the math in the article. But more because the conclusions made in the article were unpleasant for LN fans. Smiley


Was it? Did you read the comments/replies?

One of them cared enough to wrote a blog of his own after reading Jonald Fyookball's blog, https://medium.com/@murchandamus/i-have-just-read-jonald-fyookballs-article-https-medium-com-jonaldfyookball-mathematical-fd112d13737a

There was Bram Cohen in the comments too, and challenged the math, and called Joland Fyookball "stupid".
Of course I read this blog.

Look carefully at the phrase at the end:
Quote
As the model on which Fyookball is basing their calculations is already far-fetched, I will not bother addressing the math.
In fact, the author of this comment just couldn't understand the article.

The article considers a different model ( in the form of a tree), because this model should give the best results. It does not state that LN will have a model in the form of a tree. And if even for the most optimal model we get bad results, then for all other models, the results will be even worse. This is a standard technique in mathematics.

I don't recall Bram Cohen's comment. Could you give a link to this comment. If in addition to the word "stupid" there are real arguments.


It's there in the responses of the blog. I remember Bram Cohen had something to say about it on Twitter as well. I will try to find it.



I was looking for hardware for Lightning, someone recommended this, https://store.start9labs.com/collections/embassy

Does anyone have reviews?
legendary
Activity: 1468
Merit: 1102
November 18, 2020, 08:15:44 PM
This is more like a real scenario. A $ 1000 channel means that you have to pay the hub $30 per year.
Maybe it's more realistic the hub won't earn $30 per year from a $1000 investment. It's not as if there's a shortage of people hodling Bitcoin, but the problem (and that may be a much bigger problem) is that LN-nodes can't use cold storage. If you have 1000 Bitcoin and you could safely increase your stash by running a LN-hub, you wouldn't mind if the revenue is small. It's still better than nothing. But switching from cold storage to a hot node isn't going to happen for a small profit.
You have an interesting way to lead a discussion. First, say that it will be more realistic if the hubs earn less. But then you claim that this will not happen, because few people will risk for a small profit and pull their funds from a cold wallet to a hot wallet that is connected to the Internet, and all the keys on this computer are open .
Either fools or fans will risk their money for a profit of less than 1% per year. Smiley
His calculations may be correct but he then tries to "use" them to prove his point.
What a scoundrel. SmileySmileySmiley
legendary
Activity: 3290
Merit: 16489
Thick-Skinned Gang Leader and Golden Feather 2021
November 18, 2020, 03:38:05 PM
If you have 1 BTC, wouldn't it be better to open 10 X 0.1 channels, or even 100 X 0.01 channels which would make you a mini-hub that others could then start connecting to?
It depends Wink Opening 100 channels eats up on-chain fees. One large channel with a well-connected node saves those fees.

This is more like a real scenario. A $ 1000 channel means that you have to pay the hub $30 per year.
Maybe it's more realistic the hub won't earn $30 per year from a $1000 investment. It's not as if there's a shortage of people hodling Bitcoin, but the problem (and that may be a much bigger problem) is that LN-nodes can't use cold storage. If you have 1000 Bitcoin and you could safely increase your stash by running a LN-hub, you wouldn't mind if the revenue is small. It's still better than nothing. But switching from cold storage to a hot node isn't going to happen for a small profit.

~snip~
Please fix your quote, that's not my text.
legendary
Activity: 3892
Merit: 6012
Decentralization Maximalist
November 18, 2020, 12:56:26 PM
If we want to objectively assess the prospects for LN, we should not look at atypical cases. They don't make the weather. Smiley
We need to see how 90% of the standard participants will behave. For example, how will 90% of customers use LN? How will 90% of sellers use LN? What will be 90% of the LN network nodes? Is it profitable for these 90% to keep an LN node?
These are not atypical cases. They're the majority of the larger service providers I mentioned - in the case LN is popular and successful. I should have written "there are several categories of entities" instead -  I am sure you also did understand it that way (but my non-native English may have given you the opportunity for this "answer") Wink And no, we don't need 90% to be "profitable" in the sense that they make money charging fees. It is enough if the money they save in comparison to on-chain fees, all costs (opening/closing channels etc.) included, is > 0.

Quote
Unfortunately for you, mathematics is a neutral science.
His calculations may be correct but he then tries to "use" them to prove his point (which he has sustained during years here in this forum) that LN is not viable. And this exceeds the field of mathematics but enters the field of politics.

If you had read my post completely, you may have seen that I even agree with him that a completely distributed LN where most participants are well-connected, without hubs, is probably very difficult to achieve (and would also not be necessary, imo). But Fyookball didn't address the point that there are many entities who are incentived to run well-connected mini-hub nodes without having to profit directly from them. Their profits come not primarily from the fees they earn, but from the fees they save.

(I will not continue this discussion cluttering the thread, but leave it again for more technical FAQs.)
legendary
Activity: 1468
Merit: 1102
November 18, 2020, 12:53:10 PM


In 2017, there was an article dedicated to this issue.
https://medium.com/@jonaldfyookball/mathematical-proof-that-the-lightning-network-cannot-be-a-decentralized-bitcoin-scaling-solution-1b8147650800

Unfortunately, it was ignored by the Bitcoin community. Partly because they couldn't understand the math in the article. But more because the conclusions made in the article were unpleasant for LN fans. Smiley


Was it? Did you read the comments/replies?

One of them cared enough to wrote a blog of his own after reading Jonald Fyookball's blog, https://medium.com/@murchandamus/i-have-just-read-jonald-fyookballs-article-https-medium-com-jonaldfyookball-mathematical-fd112d13737a

There was Bram Cohen in the comments too, and challenged the math, and called Joland Fyookball "stupid".
Of course I read this blog.

Look carefully at the phrase at the end:
Quote
As the model on which Fyookball is basing their calculations is already far-fetched, I will not bother addressing the math.
In fact, the author of this comment just couldn't understand the article.

The article considers a different model ( in the form of a tree), because this model should give the best results. It does not state that LN will have a model in the form of a tree. And if even for the most optimal model we get bad results, then for all other models, the results will be even worse. This is a standard technique in mathematics.

I don't recall Bram Cohen's comment. Could you give a link to this comment. If in addition to the word "stupid" there are real arguments.
legendary
Activity: 2898
Merit: 1823
November 18, 2020, 11:58:46 AM
Yes. It may not have been the best example indeed. Here's another one: I think a node with 1 BTC in LN can process 10 BTC per day in transactions (given the right circumstances). At 0.25% fee that would earn 25 mBTC fees per day. Seeing this numbers makes me think it's not very likely to happen any time soon though, 0.25% is very high. For my last transaction I paid about 0.01% in fee. And that fee is for all nodes involved in the route.
If you can earn 1 mBTC by transfaring 10 BTC per day though a node that holds 1 BTC, it's still a pretty good profit.
Unfortunately, you are assuming the most fantastic scenario. Smiley

The math of LN Economics is pretty poor.

Let's consider the most efficient option: one LN node and many end users connected to this node.  The node must invest the same amount as all users do. If the node wants to earn 3% of the profit for the year, then all users will have to pay this 3%. That is, on average, each user will pay 3% per year of the amount invested in the channel. (The average route length will be 2).

As for me, this already raises doubts about the economic viability of the LN system.

If we consider a more distributed system of LN nodes, the average route length will increase. Accordingly, the investment efficiency will decrease. In order for nodes to earn 3% a year from their invested funds, users will already have to pay 2*3% or even 3*3% of their funds in the channel. The longer the average route length, the higher the coefficient.

"Super-cheap transactions in LN" and "LN-nodes that make a profit" are mutually exclusive things. Smiley

In 2017, there was an article dedicated to this issue.
https://medium.com/@jonaldfyookball/mathematical-proof-that-the-lightning-network-cannot-be-a-decentralized-bitcoin-scaling-solution-1b8147650800

Unfortunately, it was ignored by the Bitcoin community. Partly because they couldn't understand the math in the article. But more because the conclusions made in the article were unpleasant for LN fans. Smiley


Was it? Did you read the comments/replies?

One of them cared enough to wrote a blog of his own after reading Jonald Fyookball's blog, https://medium.com/@murchandamus/i-have-just-read-jonald-fyookballs-article-https-medium-com-jonaldfyookball-mathematical-fd112d13737a

There was Bram Cohen in the comments too, and challenged the math, and called Joland Fyookball "stupid".
legendary
Activity: 3724
Merit: 3063
Leave no FUD unchallenged
November 18, 2020, 10:28:19 AM
Fyookball isn't an "independent researcher", he's clearly a big blocker and probably a Bitcoin Cash supporter. That's ok for me but his postings (on his blog and here) shouldn't be considered neutral science.
Don't believe the math in the article, because the author is a big block proponent. SmileySmileySmiley  Funny.
Unfortunately for you, mathematics is a neutral science.

Contrary to popular belief, numbers can lie if you're clever about it.  How else do you explain companies cooking the books on their accounting or the popular expression "lies, damn lies and statistics".

The question always becomes "what numbers did they deliberately leave out"?

I'm sure a fraud like Faketoshi would insist that his numbers add up too, but we know better.    Wink



//EDIT:  Apologies LoyceV.  I need to stop using my phone when replying to multi-quote posts, heh.  Too easy to select the wrong text on touchscreen devices.
legendary
Activity: 1468
Merit: 1102
November 18, 2020, 06:15:15 AM
I'll try a more realistic one: how about you get $1000 salary once a month, and pay your normal bills with it? Bills will go from high amounts like your rent to daily small amounts for coffee. Then you indeed can't use the same funds several times. It becomes slightly better if you receive your salary every week. You probably don't want an open channel with your employer (I wouldn't want them to know my remaining balance), so you'll still need a third party.
This is more like a real scenario. A $ 1000 channel means that you have to pay the hub $30 per year.
If you make an average of 1 transaction per day, 360 per year, then you will get an average of $30/360 - 8 cents per transaction.
If there are 10 transactions every day, then 0.8 cents. But this is unlikely. After all, if we are considering the option with a single hub, then all your counterparties must be connected to this hub.
8 cents per transaction-this is already comparable to transactions in another blockchain. For example, take dash. There are instant payments that can be made for ~10 cents per transaction. And at the same time, you don't need any centralized hub, you don't need channels, you don't need a third party to replenish the channel. The question is, what will users prefer?

Is it unprofitable to keep an LN node? This means that there will be few nodes, and their number will not grow. What we have now.
There are SEVERAL entities which would benefit from a LN node even if their income from LN fees is tiny.
If we want to objectively assess the prospects for LN, we should not look at atypical cases. They don't make the weather. Smiley
We need to see how 90% of the standard participants will behave.

For example, how will 90% of customers use LN? How will 90% of sellers use LN?

What will be 90% of the LN network nodes? Is it profitable for these 90% to keep an LN node?

Quote
Fyookball isn't an "independent researcher", he's clearly a big blocker and probably a Bitcoin Cash supporter. That's ok for me but his postings (on his blog and here) shouldn't be considered neutral science.
Don't believe the math in the article, because the author is a big block proponent. SmileySmileySmiley  Funny.
Unfortunately for you, mathematics is a neutral science.
legendary
Activity: 3626
Merit: 2209
💲🏎️💨🚓
November 17, 2020, 09:32:46 PM
Again, an unrealistic scenario.Smiley

 I (like most users) don't get paid$ 10 many times over the course of a month. I usually only pay$10. After 10 payments, my channel  will be reset to zero. And you will need to either re-create the channel, or replenish it using a third-party service. And this is the fee for an additional  on-chain transaction.
I'll try a more realistic one: how about you get $1000 salary once a month, and pay your normal bills with it? Bills will go from high amounts like your rent to daily small amounts for coffee. Then you indeed can't use the same funds several times. It becomes slightly better if you receive your salary every week. You probably don't want an open channel with your employer (I wouldn't want them to know my remaining balance), so you'll still need a third party.

I have some funds in a Blue wallet that I don't mind exchanging 1:1 for on-chain funds - (you) pay the TX fees on your end and I do likewise.  Having no funds on your end is good as it enables you to have inbound capacity when you open a new channel.



Just an aside for a previous comment in the thread:

If you have 1 BTC, wouldn't it be better to open 10 X 0.1 channels, or even 100 X 0.01 channels which would make you a mini-hub that others could then start connecting to?
legendary
Activity: 3892
Merit: 6012
Decentralization Maximalist
November 17, 2020, 08:19:56 PM
Is it unprofitable to keep an LN node? This means that there will be few nodes, and their number will not grow. What we have now.
There are several entities which would benefit from a LN node even if their income from LN fees is tiny. The most obvious examples are exchanges and other custodial wallet providers. But there are others, like arbitrageurs (we discussed that some pages ago), but also online merchants (from a certain size upwards).

This would lead, if we take the graphics above, to a scenario closer to the middle one from Fyookball's blog post, but I would argue that these "indirectly profitting nodes" would try to be more well connected than in this example where each one has only 2-3 connections to nearby nodes. So we would have, at the end, a network between the "decentralized" and the "distributed" model, with clearly identifiable hubs, but which would be much better connected than in the example.

This however depends again from popularity of the LN itself (only a few of these entities do not depend from incentives which are related to the size/network effect of LN), which brings us back to the chicken-and-egg problem we discussed in the pages before. Clearly, exchanges could be the "boosters" of LN if they bring the arbitrage business "on board", and this already could mean a significant growth. But for now afaik Bitfinex is the only larger exchange which supports LN fully, so arbitrage via LN still doesn't make sense.

Fyookball isn't an "independent researcher", he's clearly a big blocker and probably a Bitcoin Cash supporter. That's ok for me but his postings (on his blog and here) shouldn't be considered neutral science.
legendary
Activity: 3290
Merit: 16489
Thick-Skinned Gang Leader and Golden Feather 2021
November 17, 2020, 01:04:46 PM
Again, an unrealistic scenario.Smiley

 I (like most users) don't get paid$ 10 many times over the course of a month. I usually only pay$10. After 10 payments, my channel  will be reset to zero. And you will need to either re-create the channel, or replenish it using a third-party service. And this is the fee for an additional  on-chain transaction.
I'll try a more realistic one: how about you get $1000 salary once a month, and pay your normal bills with it? Bills will go from high amounts like your rent to daily small amounts for coffee. Then you indeed can't use the same funds several times. It becomes slightly better if you receive your salary every week. You probably don't want an open channel with your employer (I wouldn't want them to know my remaining balance), so you'll still need a third party.
legendary
Activity: 1468
Merit: 1102
November 17, 2020, 10:17:23 AM
[
Quote
Let's consider the most efficient option: one LN node and many end users connected to this node.  The node must invest the same amount as all users do. If the node wants to earn 3% of the profit for the year, then all users will have to pay this 3%. That is, on average, each user will pay 3% per year of the amount invested in the channel. (The average route length will be 2).
3% sounds bad if you spend $1000 per month. But if you put $100 in a channel, and spend and receive $10 at a time, but do that 50 times per month, then $3 in fees doesn't sound bad at all! I spent more on my last on-chain Bitcoin transaction (I made a mistake on the fees, my fault).
Again, an unrealistic scenario.Smiley

 I (like most users) don't get paid$ 10 many times over the course of a month. I usually only pay$10. After 10 payments, my channel  will be reset to zero. And you will need to either re-create the channel, or replenish it using a third-party service. And this is the fee for an additional  on-chain transaction.

Quote
Quote
"Super-cheap transactions in LN" and "LN-nodes that make a profit" are mutually exclusive things. Smiley
You're probably right here. But I don't really mind, it's not as if Bitcoin nodes are currently making a profit. Some things are just done to support the network, and if an exchange (or casino) runs a LN-node, earning money from transaction routing is only a side-income, and not their core business.
Is it unprofitable to keep an LN node? This means that there will be few nodes, and their number will not grow. What we have now.
copper member
Activity: 2856
Merit: 3071
https://bit.ly/387FXHi lightning theory
November 17, 2020, 09:25:19 AM
Unfortunately, you are assuming the most fantastic scenario. Smiley
What can I say, I'm an optimist Smiley

Quote
Let's consider the most efficient option: one LN node and many end users connected to this node.  The node must invest the same amount as all users do. If the node wants to earn 3% of the profit for the year, then all users will have to pay this 3%. That is, on average, each user will pay 3% per year of the amount invested in the channel. (The average route length will be 2).
3% sounds bad if you spend $1000 per month. But if you put $100 in a channel, and spend and receive $10 at a time, but do that 50 times per month, then $3 in fees doesn't sound bad at all! I spent more on my last on-chain Bitcoin transaction (I made a mistake on the fees, my fault).

Quote
"Super-cheap transactions in LN" and "LN-nodes that make a profit" are mutually exclusive things. Smiley
You're probably right here. But I don't really mind, it's not as if Bitcoin nodes are currently making a profit. Some things are just done to support the network, and if an exchange (or casino) runs a LN-node, earning money from transaction routing is only a side-income, and not their core business.

Quote
I must admit I don't have the time to read it in-depth now. But I like this picture:
Image loading...
The thing is: I'm okay with the scenario on the left, if that means I can make many small cheap payments using Bitcoin. I'd prefer a fully decentralized system, but I get that won't happen.

Dont eos have around 22 trusted nodes mining everything in a decentralised style way? Id be happy with something like that, or just with the idea that you make a payment regularly with and have a channel open to a local store who would want the fee for processing your transaction...

If santander charged €30 for a transfer I see no reason Deutsche or Lloyd's wouldn't want to try to bring it down to €25 if they can..

3% fees are high - i wouldn't want to pay that much compared to if I could make a bank transfer.
legendary
Activity: 3290
Merit: 16489
Thick-Skinned Gang Leader and Golden Feather 2021
November 17, 2020, 08:55:26 AM
Unfortunately, you are assuming the most fantastic scenario. Smiley
What can I say, I'm an optimist Smiley

Quote
Let's consider the most efficient option: one LN node and many end users connected to this node.  The node must invest the same amount as all users do. If the node wants to earn 3% of the profit for the year, then all users will have to pay this 3%. That is, on average, each user will pay 3% per year of the amount invested in the channel. (The average route length will be 2).
3% sounds bad if you spend $1000 per month. But if you put $100 in a channel, and spend and receive $10 at a time, but do that 50 times per month, then $3 in fees doesn't sound bad at all! I spent more on my last on-chain Bitcoin transaction (I made a mistake on the fees, my fault).

Quote
"Super-cheap transactions in LN" and "LN-nodes that make a profit" are mutually exclusive things. Smiley
You're probably right here. But I don't really mind, it's not as if Bitcoin nodes are currently making a profit. Some things are just done to support the network, and if an exchange (or casino) runs a LN-node, earning money from transaction routing is only a side-income, and not their core business.

Quote
I must admit I don't have the time to read it in-depth now. But I like this picture:
Image loading...
The thing is: I'm okay with the scenario on the left, if that means I can make many small cheap payments using Bitcoin. I'd prefer a fully decentralized system, but I get that won't happen.
legendary
Activity: 1468
Merit: 1102
November 17, 2020, 08:28:23 AM
Yes. It may not have been the best example indeed. Here's another one: I think a node with 1 BTC in LN can process 10 BTC per day in transactions (given the right circumstances). At 0.25% fee that would earn 25 mBTC fees per day. Seeing this numbers makes me think it's not very likely to happen any time soon though, 0.25% is very high. For my last transaction I paid about 0.01% in fee. And that fee is for all nodes involved in the route.
If you can earn 1 mBTC by transfaring 10 BTC per day though a node that holds 1 BTC, it's still a pretty good profit.
Unfortunately, you are assuming the most fantastic scenario. Smiley

The math of LN Economics is pretty poor.

Let's consider the most efficient option: one LN node and many end users connected to this node.  The node must invest the same amount as all users do. If the node wants to earn 3% of the profit for the year, then all users will have to pay this 3%. That is, on average, each user will pay 3% per year of the amount invested in the channel. (The average route length will be 2).

As for me, this already raises doubts about the economic viability of the LN system.

If we consider a more distributed system of LN nodes, the average route length will increase. Accordingly, the investment efficiency will decrease. In order for nodes to earn 3% a year from their invested funds, users will already have to pay 2*3% or even 3*3% of their funds in the channel. The longer the average route length, the higher the coefficient.

"Super-cheap transactions in LN" and "LN-nodes that make a profit" are mutually exclusive things. Smiley

In 2017, there was an article dedicated to this issue.
https://medium.com/@jonaldfyookball/mathematical-proof-that-the-lightning-network-cannot-be-a-decentralized-bitcoin-scaling-solution-1b8147650800

Unfortunately, it was ignored by the Bitcoin community. Partly because they couldn't understand the math in the article. But more because the conclusions made in the article were unpleasant for LN fans. Smiley
legendary
Activity: 2898
Merit: 1823
November 17, 2020, 04:15:24 AM
But payment channels, and their capacity, are actually limited by how much Bitcoin the people who run nodes hold, are limited by how much capital they want to open payment channels with, are limited with their technical-skills in how to maintain the node/balance channels.

And if they are a smaller public node, like one of mine. If they have a need for the BTC someplace else.
I just moved all the funds out of one of nodes because I was to tired to deal with moving some funds out of cold storage.

It's part of the reason why commercial businesses are critical here IMO. They have a plan, they put the funds in and leave them there and keep them balanced.
Unlike Dave who puts them in and plays around and then pulls them to get a new laptop because the charging port on this one is wonky and going to fail sooner or later.

-Dave


That's it! That's the point! Because if the capital "invested" in LN payment channels could earn you profit, enough to make it have a feasible rate of "investment", then the more sensible thing to do is, leave the "investment" alone and look for another way to buy the new laptop.

Capital is limited. I believe the altruism that boot-strapped LN would be replaced by participants based on incentives.
legendary
Activity: 3290
Merit: 16489
Thick-Skinned Gang Leader and Golden Feather 2021
November 16, 2020, 03:53:11 PM
I honestly don't understand why that comparison.
My point is: you don't need a large balance on a node to be able to make many transactions, as long as you have transactions in both directions.

Quote
Plus isn't the 24 hour volume from your link, trading volume, not transaction volume?
Yes. It may not have been the best example indeed. Here's another one: I think a node with 1 BTC in LN can process 10 BTC per day in transactions (given the right circumstances). At 0.25% fee that would earn 25 mBTC fees per day. Seeing this numbers makes me think it's not very likely to happen any time soon though, 0.25% is very high. For my last transaction I paid about 0.01% in fee. And that fee is for all nodes involved in the route.
If you can earn 1 mBTC by transfaring 10 BTC per day though a node that holds 1 BTC, it's still a pretty good profit.
legendary
Activity: 3458
Merit: 6231
Crypto Swap Exchange
November 16, 2020, 09:53:29 AM
But payment channels, and their capacity, are actually limited by how much Bitcoin the people who run nodes hold, are limited by how much capital they want to open payment channels with, are limited with their technical-skills in how to maintain the node/balance channels.

And if they are a smaller public node, like one of mine. If they have a need for the BTC someplace else.
I just moved all the funds out of one of nodes because I was to tired to deal with moving some funds out of cold storage.

It's part of the reason why commercial businesses are critical here IMO. They have a plan, they put the funds in and leave them there and keep them balanced.
Unlike Dave who puts them in and plays around and then pulls them to get a new laptop because the charging port on this one is wonky and going to fail sooner or later.

-Dave
legendary
Activity: 2898
Merit: 1823
November 16, 2020, 07:52:22 AM
But payment channels, and their capacity, are actually limited by how much Bitcoin the people who run nodes hold, are limited by how much capital they want to open payment channels with, are limited with their technical-skills in how to maintain the node/balance channels.

That limitation, and increase in demand for LN transactions = higher fees?
Let's compare it to Tether for a moment: it's 24h volume is more than twice it's market cap. Each coin is "used" several times per day. The same will happen for LN-nodes, and the same happens with actual dollar coins and banknotes too.


I honestly don't understand why that comparison. Plus isn't the 24 hour volume from your link, trading volume, not transaction volume?
legendary
Activity: 3290
Merit: 16489
Thick-Skinned Gang Leader and Golden Feather 2021
November 16, 2020, 05:29:22 AM
But payment channels, and their capacity, are actually limited by how much Bitcoin the people who run nodes hold, are limited by how much capital they want to open payment channels with, are limited with their technical-skills in how to maintain the node/balance channels.

That limitation, and increase in demand for LN transactions = higher fees?
Let's compare it to Tether for a moment: it's 24h volume is more than twice it's market cap. Each coin is "used" several times per day. The same will happen for LN-nodes, and the same happens with actual dollar coins and banknotes too.
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