Would it cost anything to open a Channel on Lightning Network?

[Carlton Banks]

if that's right, many users will keep their payments offline forever: if you only receive 0.00005BTC through LN, it's not even enough to pay for a Bitcoin fee, so all Bitcoin dust stays off-chain.

Yep, that's the idea. But not really for 500 bits (as in your example), if Lightning is successful enough then 500 bits could be economic to send on-chain again. Lighting really unlocks amounts less than that, 100's of satoshi, or even less than 1 satoshi (i.e. milli-satoshis. Lightning expresses BTC amounts in millisatoshis I believe)

[Samarkand]

... This routing of payments will either be extremely cheap or have no cost, depending on whether node operators in the route charge a fee for being routed through.
...

Has it already been specified what is necessary to run your own Lightning Network node?
I guess that you would need one of the Lightning Network clients alongside with enough
locked Bitcoin to provide liquidity. Besides, it is probably necessary to be connected to the internet
in order to route transactions.

Which other requirements do I miss?

[LoyceV]

if Lightning is successful enough then 500 bits could be economic to send on-chain again.

I highly doubt that. If 10 million people make only one on-chain transaction per month, 1 MB blocks are full already.

Lightning expresses BTC amounts in millisatoshis I believe)

I can't wait for it to happen!

[Vigme86]

Can I please get answers to these questions  

1.  Would opening a Payment Channel on Lightning Network cost any fee?

2. Can one open a payment channel with an individual (& not just companies) ?

3.  Would payment channels continue to be opened or exist after its bitcoins has been exhausted?

4. Can I withdraw my bitcoin from  payment channel whenever I want?  If yes, does it cost anything to do this?

Point 1. and point 3. are kind of part of the points that confuses me on LN stuff, if I may I would like to detail it more.

If I have good understood, once LN will be avaible for mass adoption, as a user you have to make a multi-sig special transaction on-chain
to create the channel, and if you or your counterpart will link to other users with other channels, and so on, in that case you're creating the famous Lightning Network (LN), off-chain, to transact between multiple users.
Then each transaction on the channel will be off-chain until channel will not be closed, but transactions on-channel, thus off-chain, will not be feeless, and each transaction will cost a fee to pay LN nodes between you and the user you want to pay and viceversa.

Thus there will be on-chain fees, collected by miners as of today, and off-chain fees, collected by LN users.

My questions are:
- Who pays on-chain fees? A and B I suppose, right? In equal shares? 30% 70%? 70% 30%? How will be calculated?

- How will be calculated off-chain fees ?

- In my view, off-chain fees will be collected by users who can afford running a full-node running 24h 7d with multiple opened channels, that could be   kind of an interesting business not for miners but for simple users also, or not?

- Once you will have a LN with multiple channels, how do you balance between them once a channel between two users (A and B), and hence the bitcoin encumbered on-chain within that transaction, will be released?
It's highly unlikely they will be still entirely between A and B wallets, quite the contrary, some part of them will be paid as off-chain fees, others will be sent to other users (let's say C and D), which though remain with opened channels. What will happen in that event to those bitcoins? I suppose they will be avaiable on-chain to C and D wallets, but it seems kind of risky to me, because you could create negative balances on the Lighting Network, how do you manage that?
Let's say C has a 0,5 BTC balance off-chain, A and B close their channel, doing that C "earns" 1 BTC in his on-chain wallet and "lose" 1 BTC in his LN off-chain, hence with a balance off-chain in the LN of -0,5 BTC. What will happen if he closes all his channels?

Thanks in advance  

Really ? Anyone ? Are they kind of newbie questions for you ?

[Carlton Banks]

if Lightning is successful enough then 500 bits could be economic to send on-chain again.

I highly doubt that. If 10 million people make only one on-chain transaction per month, 1 MB blocks are full already.

Your math is right. Your figures are wrong: 1MB is not the blocksize any longer.

And your logic is wrong too. When millions of transactions per day are being made over Lightning, the price users are willing to pay on-chain is going to be less. Why wait minutes or hours when most transactions can be made in less than a second? Why pay 100,000 times the fees? Demand will follow supply, and fees will adjust commensurately.

[LoyceV]

if Lightning is successful enough then 500 bits could be economic to send on-chain again.

I highly doubt that. If 10 million people make only one on-chain transaction per month, 1 MB blocks are full already.

Your math is right. Your figures are wrong: 1MB is not the blocksize any longer.

I thought about that, but ignored it: even if you do the math with 4 MB blocks, it's just 4 times more users or 4 times more transactions.

And your logic is wrong too. When millions of transactions per day are being made over Lightning, the price users are willing to pay on-chain is going to be less. Why wait minutes or hours when most transactions can be made in less than a second?

That would mean many users would never settle their transactions on-chain anymore. That means the small amounts they have in their future Lightning Wallet have the potential to be settled on-chain, but they never do it because it's easier/cheaper not to? Can you even call it Bitcoin if they never go on-chain?

[Carlton Banks]

Can you even call it Bitcoin if they never go on-chain?

Why not?

[Quickseller]

if Lightning is successful enough then 500 bits could be economic to send on-chain again.

I highly doubt that. If 10 million people make only one on-chain transaction per month, 1 MB blocks are full already.

Your math is right. Your figures are wrong: 1MB is not the blocksize any longer.

And your logic is wrong too. When millions of transactions per day are being made over Lightning, the price users are willing to pay on-chain is going to be less. Why wait minutes or hours when most transactions can be made in less than a second? Why pay 100,000 times the fees? Demand will follow supply, and fees will adjust commensurately.

Users will have to periodically close/settle LN channels for a variety of reasons even if fees are high. If participants of LN channels start to act maliciously, channels will be forced to close, when channels have nearly all of the balances on one side, the other side will want to close the channel to reduce risk, channels will be opened and closed as users start/stop using bitcoin, businesses will close channels as they accumulate large amounts of bitcoin so they can move coins to cold storage, etc.

[LoyceV]

Can you even call it Bitcoin if they never go on-chain?

Why not?

Although philosophical, it doesn't feel right.

Users will have to periodically close/settle LN channels for a variety of reasons even if fees are high. If participants of LN channels start to act maliciously, channels will be forced to close, when channels have nearly all of the balances on one side, the other side will want to close the channel to reduce risk

Isn't "closing channels" very easy to abuse? Say a LN hub pays me 0.0000001 Bitcoin, if I understand correctly I can close that channel whenever I want. I won't have enough funds to pay the fee, but the hub does. Does this mean the hub has to pay many times more than what it paid me in fees?
Or is there a safeguard in place that I don't know about? If it is like I just described, a spam attack can easily bankrupt LN hubs.

[Carlton Banks]

Users will have to periodically close/settle LN channels for a variety of reasons even if fees are high. If participants of LN channels start to act maliciously, channels will be forced to close, when channels have nearly all of the balances on one side, the other side will want to close the channel to reduce risk, channels will be opened and closed as users start/stop using bitcoin, businesses will close channels as they accumulate large amounts of bitcoin so they can move coins to cold storage, etc.

I made a basic supply and demand argument. Lightning channels adds several orders of magnitude more transaction capacity for sending BTC between users. A list of conditions under which channels close is not very meaningful as a response.

Although philosophical, it doesn't feel right.

Philosophy involves reasoning. Feelings do not.