15
votes
Accepted
What is a hash pre-image as it is used for the breach remedy?
In the image below from Rusty Russell's Deployable Lightning paper, you can see a visualization of the commitment transactions and their outputs:
For each payment in a channel, there are two ...
- 11.8k
15
votes
How does Lightning transaction revocation work?
When you open a lightning channel, you will receive from the other person their revocation_basepoint, and for each commitment transaction, you will send to the other person a per_commitment_point. The ...
- 68.6k
7
votes
Accepted
Transaction overriding in lightning network
Lightning payment channels are established by two parties Alice and Bob paying into a 2-of-2 multisignature address. Concurrently, they create two "exit-transactions", one for each participant which ...
- 72.8k
4
votes
Is eltoo more memory efficient for watchtowers?
Without eltoo (ie today) a watchtower needs to store a different justice transaction for every channel update in case the channel counterparty broadcasts (deliberately or accidentally) an expired ...
- 14.7k
4
votes
Lightning: Why would Bitcoin Network Accept a Breach Remedy?
You are right. If the dishonest party publishes an outdated commitment transaction it is most likely be accepted by the Bitcoin network.
The key trick is that the old state has an output script that ...
- 11.8k
3
votes
Order of Exchanging Revocation Keys during Lightning Transactions
Alice and Bob jointly create a public key R for each revocable output (RSMC output script).
They each privately generate r-1 and r-2, and derive public keys R-1 and R-2 from these. R is the sum of R-...
- 2,501
3
votes
Accepted
Lightning Network: what happens if parties lose their txs?
Yes that is correct. Bob's revocation secret is used as an insurance policy for Alice. If she loses it, Bob will be able to act maliciously and get away with it.
However, I want to add two things:
...
- 11.8k
2
votes
Lightning incentive for micro-cheating?
When the total capacity of the channel is less than it costs to close the channel, neither party has an incentive to close the channel.
If broadcasting an outdated commitment transaction returns some ...
- 72.8k
2
votes
How is a doublespend prevented in the Lightning Network?
Alice and Bob open a channel with a fixed balance equal to the amount in the multi-sig address. The channel opens with a balance sheet which includes proof for both Alice and Bob’s balance.
Every ...
- 21
2
votes
How is a doublespend prevented in the Lightning Network?
Based on your comments, I think one fundamental issue you're missing is that to pay with LN, the other party has to be online at the time. There's no question of "what happens if Bob is offline" ...
- 19.7k
2
votes
How is a doublespend prevented in the Lightning Network?
Doublespends are not possible, because a payment on LN is only considered finalized once both payment channel owners have revoked the previous state of the payment channel by handing their partner a ...
- 72.8k
2
votes
Accepted
Lightning Network: hashlocks vs private keys exchange
So the question is: are commitment transactions between two nodes revoked through hashlocks or through private keys exchange?
Either way will work, but hashlocks are simpler. They're described in ...
- 29.3k
2
votes
Is there any tech that uses a signature as a private key?
It seems that publishing a transaction that shouldn't be published (a
"bad act") must involve publishing something the victim can use to
unwind everything.
Really, I should have asked the ...
- 793
2
votes
Accepted
What is the cost of resolving a Lightning channel breach?
The cost is proportional to the number of committed HTLCs on the channel at the time of closure. Each HTLC has an output in the commitment transaction which pays into either a HTLC-success transaction ...
- 3,324
2
votes
Accepted
Can miners collude to bypass the penalty based revocation system of the lightning network?
When a channel is closed unilaterally, it requires two transactions by the closing party to move funds from a channel back into unilateral control.
The closing party publishes their version of the ...
- 72.8k
2
votes
Can miners collude to bypass the penalty based revocation system of the lightning network?
It's named "penalty transaction" by the specs :).
What you say is true but far from sufficient. It also requires this miner be able to heal this block chain without a censored (the penalty) ...
- 7,097
2
votes
Accepted
Question about Payment Channels
I think I see where the confusion is, but please correct me if I'm not quite understanding your question.
It's possible to misinterpret that section in Mastering Bitcoin as saying that there is one ...
- 373
2
votes
Watchtower limitations and possible solutions so far in 2021-Nov?
The capacity of the lightning network seems to ride on the "trust" of the counterparty you are opening a channel with along with the additional layer of trusting a watchtower to keep your ...
- 14.7k
1
vote
Accepted
How can I recover a Core Lightning node as safely as possible if the backups might be out of date?
This is a really good question.
Is it safer to try using the emergency.recover file first? If the peer cooperates, is this completely safe? If the peer tries to cheat me, do I still have time to use ...
- 1,358
1
vote
Accepted
Using multiple penalty transactions to increase max HTLCs per LN channel
Are there any significant hurdles preventing us from using multiple penalty transactions, where the nth penalty transaction spends HTLCs [n*483; (n+1)*483[ from the commitment transaction? At first ...
- 11.8k
1
vote
How to transmit fraudulent commitment transaction on lightning channel?
As far as I know the lightning clients that I know of (LND, c-lightning) do not offer this possibility through their API.
So you'd be right to patch the code yourself. For LND, you should have a look ...
- 285
1
vote
Lightning: Why would Bitcoin Network Accept a Breach Remedy?
1) An invalid commitment transaction remains a valid transaction on the bitcoin network until the funding TX output is spent.
Each commitment transaction, once signed will remain valid until the ...
- 2,501
1
vote
Lightning: Why would Bitcoin Network Accept a Breach Remedy?
The assumption in your last question is wrong, since there is no exclusivity in the publishing of both transactions. They can be accepted into the ledger and as a matter of fact, the subsequent ...
- 141
1
vote
Transaction overriding in lightning network
A commitment transaction is a transaction that sends person A's bitcoins to person A, and person B's bitcoins to an intermediate address (let's call it B*). B* can be spent by person B, but only after ...
- 1,569
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