Questions tagged [hash-time-locked-contract]
A Hash Time Locked Contract (HTLC) is a conditional payment that requires the recipient to reveal a hash preimage. It also includes a time lock clause that allows the payment to be refunded after a certain time. HTLCs are used in Lightning Network channels, atomic swaps and other protocols.
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Script for Success of HTLC in the Lightning Network
BOLT #3 specifies that an HTLC success transaction (the second-stage transaction that spends an HTLC by providing the preimage) has the witness script 0 <remotehtlcsig> <localhtlcsig> <...
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Using multiple penalty transactions to increase max HTLCs per LN channel
BOLT#2 states the below as one rationale to limit a Lighting Network channel to 483 HTLCs:
It also ensures that a single penalty transaction can spend the entire commitment transaction, as calculated ...
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Opportunity cost of coins locked in HTLC
If a party agrees to lock coins in HTLC for payment (having hashlock for time T), and it receives a fee f if the HTLC succeeds, then does it mean that the opportunity cost of coins locked in HTLC is f?...
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Signing taproot key-path transaction from rust-bitcoin
I'm trying to make a taproot HTLC using rust-bitcoin for an atomic swap protocol. My plan is that in the "happy case" of my protocol, the coins are spent with the key-path, and then there is ...
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LN-Channel: Do I have to use new private keys for each HTLCs out of security?
I have a question regarding the security of HTLCs in a LN-channel.
In a LN-transaction with multiple HTLCs (routings) to the destination one is using the signature of each node provider so that the ...
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What is involved in the "database compaction" of a LND node?
As lightning network channels route payments, channel updates require the 2 channel peers (Alice & Bob) to do a round of signing and trade commitment transactions for the most up-to-date channel ...
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What Lightning Network transaction information is usable to provide a verifiable public index of received payments?
I have in mind a protocol architecture that includes value transfer, where BTC is the unit of account.
To make the protocol scalable I could specify use of the Lightning Network protocol.
In this case,...
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What prevent users from cheating in an HTLC contract
I was reading about HTLC and how Charlie have to create a random number and generates its SHA256 hash that is supposed to be used by Bob in the end to finalize the payment he has received from Alice.
...
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Can eltoo's no-penalty design be exploited by malicious submissions of old state?
Eltoo uses the no-penalty submission mechanism, where the cost for an adversary to submit an old state is the transaction fee. This action seems unprofitable, but if we add HTLC to Eltoo, things seem ...
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Unilateral close because of HTLC in remote commitment
I run lnd on my node and sometimes see messages like this:
[INF] CNCT: ChannelArbitrator(CHANPOINT): immediately failing htlc=HTLCID from remote commitment
The corresponding close transaction sent ...
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Lightning protocol modification for app
I'm currently building a Lightning platform for online sellers. I have found that timing can be very problematic: For example, two people want to buy the last item in stock or a unique item like a ...
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Difference between capacity and max_htlc in Lightning Network?
What is the difference between capacity and max_htlc in the routing of payments in the network?
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How would PTLC's change invoices?
I am wondering how would switching from HTLCs to PTLCs change invoices? I assume there would not be a payment-hash anymore, but what would replace it. A payment-point?
Also, is there already support ...
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UNIX END TIME January 19, 2038 - Will it affect Timelock nLOCKTIME smart contracts past that date?
So UNIX END TIME is January 19, 2038.
What will happen then to the btc TX that looks at Unixtime for nLOCKTIME transactions?
Will any Locktime transaction past that date, say to 2040 be an issue? Or ...
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Is it possible to run a Lightning Network node with multiple entities holding parts of the private key?
What's the technical limitation stopping multiple entities from collectively managing an LN node?
I understand all parties (entities that share the Node private key) need to be online to sign routing/...
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Taproot PTLC: Non-Multisig partly timelocked spending conditions
(Taproot environment) What I came up with is the following logic:
$alice = A;
$bob = B;
pk($bob) || (pk($alice) && older(10))
(See on Minsc).
I looked at the generated / resulting Bitcoin ...
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What does the abbreviation "HTLC" stand for?
An HTLC is a contract making use of both a hashlock and a timelock. I noticed a discrepancy in what various sources state the abbreviation HTLC is short for. I've found:
"Hashed Timelock ...
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Can PTLCs and HTLCs be mixed along a route?
When PTLCs get introduced on the Lightning Network, do all hops along a route need to use just one of either HTLCs or PTLCs, or would it be possible to create a route where some nodes use PTLCs and ...
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What would happen to Bitcoin if GPS/Galileo timing ceased to be available?
According to this web site, the timing from a system like GPS is essential to "financial networks [which] rely on precision timing for synchronization and operational efficiency." Is the ...
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how many htlcs can a lightning channel have pending at a given time
Channels can have pending HTLCs, or even handle multiple payments concurrently. Is there a max number of pending HTLCs a channel can entertain? What is that max, why is it set to that number, and what ...
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Do BIP199's HTLCs suffer from script malleability?
Do BIP199 HTLCs suffer from sigscript malleability like multisigs do due to OP_CHECKMULTISIG?
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Atomicity on HTLC payment chain
I have a doubt about HTLC on a lightning network payment. I have this scenario:
Alice wants to pay 100 sats to David using a route she found with Bob and Chad, this would be:
Alice -> Bob -> ...
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Why, how, and when should an intermediate LN node terminate/resolve its HTLC(s) off-chain?
I once heard an attack against LN, which was called "flood & loot": https://medium.com/blockchains-huji/flood-loot-a-systemic-attack-on-the-lightning-network-5c3dac7bba24
The 3rd step of ...
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Decode script return different value from my relative timelock
I want to lock a UTXO for 90 days.
My Binary is:
00000000010000000011101101010011
And my sequence is: 533B40
When I decode the witness script with bitcoin-cli decodescript I can see 4209491.
Where ...
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What is "Link-Level Multiplexing"?
In a discussion about private channels, Conner Fromknecht mentioned a concept called Link-Level Multiplexing. What is this and what is it useful for? How does it work?
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Time locked puzzle for payment in Lightning Network
Currently HTLC's timeout transaction relies on absolute timelock enforced on the script. It allows a counterparty to withdraw the money from the contract if the other party doesn't release the ...
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Lightning Network state deprecation secret keeping
When using a lightning channel, two sides are sending transactions representing the current state (or balance) between them, and for each state sent, they invalidate the previous state by sending a ...
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Simulate HTLC in regtest c-lightning
I have three nodes in regtest environment l1, l2, and l3
l1 create a channel with l2
l2 create a channel with l3
l3 create an invoice for l1.
l1 can pays it because use the route l1-l2-l3
I presume ...
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Who bears the transaction fee for settling HTLC in Lightning Network?
Given a channel that exist between Alice and Bob, where Alice wants to transfer 0.0001 BTC to Bob. Alice makes HTLC payment to Bob contingent to the secret for the payment hash within a timelock of ...
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Reuse of payment hash in Lightning Network
Suppose there exist two such payment transfer request: A transfers 1 msat to R via A->B->C->R and S transfers 5 msat to R via S->B->C->R. Let the two HTLCs be formed across both the paths ...
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Why do multihop LN payments start settling from the recipient's end?
In HTLC, after all the parties have locked their funds in the contract, claiming payment happens in a reverse way, starting with the receiver who reveals the preimage of the corresponding payment hash....
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settling timelocked contracts based on amount of time elapsed in Lightning network
Suppose in a payment route A->B->C, A desires to pay 0.01 BTC to C. It locks in 0.01 BTC with B in the HTLC having timeout period of say 2 days and B locks 0.01 BTC with C in HTLC having timeout ...
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Why does every HTLC in a commitment transaction require its own signature?
From BOLT 02 we can learn
When a node has changes for the remote commitment, it can apply them,
sign the resulting transaction (as defined in BOLT #3), and send a
commitment_signed message.
1. type: ...
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non-mandatory-script-verify-flag (Locktime requirement not satisfied) (code 64)
I'm attempting to redeem the following htlc ( the python script below ) via timeout, however the redemption tx errors out upon validation with the error below:
bitcoin.rpc.VerifyRejectedError: {'code'...
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Can someone explain how an HTLC is redeemed?
I'm looking at Bolt 3 in the Lightning rfc. My question is about how a HTLC is redeemed. Example HTLC script for reference:
# To remote node with revocation key
OP_DUP OP_HASH160 <RIPEMD160(SHA256(...
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Why do we need revocation in both the offered/received HTLC outputs and HTLC timeout/success outputs?
The witness script for the output in the HTLC success/timeout transaction is:
OP_IF
# Penalty transaction
<revocationpubkey>
OP_ELSE
`to_self_delay`
OP_CHECKSEQUENCEVERIFY
...
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Possible race condition(double spend) on HTLC-Timeout in the lightning network?
From the offered HTLC Outputs,
# To remote node with revocation key
OP_DUP OP_HASH160 <RIPEMD160(SHA256(revocationpubkey))> OP_EQUAL
OP_IF
OP_CHECKSIG
OP_ELSE
<remote_htlcpubkey> ...
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Single-hop Payment vs Multi-hop payments
I am beginner of lightning network. When i am looking roughly lightning network whitepaper, i was confused about the types of contracts used in single-hop and multi-hop.
As far as I understand, In ...
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Do HTLCs get "carried over" in the subsequent commitment transactions?
With regular commitment transactions, current transaction invalidates the previous one. This is fine, since TXs between A and B in their channel happen one after another. However, HTLCs are sort of ...
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lightning to lightning non custodial swaps [closed]
Do you know the way to freeze funds in lightning tx to implement atomic swap between two independent lightning networks?
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Method to create P2SH address
I am trying to create a htlc smart contract manually by writing a script and finding the hex using the btcc compiler. Now node A has to create a transaction using that hex and lock money in that p2sh ...
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HTLCs and commitment transactions
Why commitment transactions can't simply be HTLCs instead of contracts revocable by having the second half of the Revocable Private Key? I mean, why bother to create a Revocable Public Key from two ...
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BOLT #3: Shouldn't timeout be included in the script of "Offered HTLC Outputs" for the local node?
According to the BOLT #3 documentation, the offered HTLC output has the following script that allows the remote node to claim the funds with the payment pre-image and the local node to claim it after ...
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Remote node signature for HTLC-success and HTLC-timeout transactions
According to BOLT #3, when constructing a HTLC output in the version of the local node (both received and offered HTLC), it requires that the payment to the local node is locked with CHECKMULTISIG ...
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How multiple unfinished payments in single LN channel work?
I think I understand HTLCs, at least if they are on chain. I also have a basic understanding of how off chain channel looks like.
I understand it as follows. It is a 2-of-2 multisig transaction ...
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Why do we use CLTV instead of CSV in the HTLC output of the commitment transaction?
In lightning network commitment transactions, the HTLC offered/received outputs generally pay the offering node after a timeout which is scripted using CLTV. In other parts of the commitment ...
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Implement HTLC manually by writing scripts
Is there any way to implement HTLC manually for locking funds in the channels in lightning network for a period of time (by setting intervals) and releasing the funds after the time lock expired using ...
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How can I create HTLCs below dust_limit_satoshi in Lightning Network?
BOLT#2 documentation for open_channel message has two points (dust_limit_satoshi and htlc_min_msat) in the data message that I found confusing. Below is the statement related to dust_limit_satoshi:
...
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"HTLCs don't work for micropayments"?
I read this tweet by Tadge Dryja recently. What exactly did he mean? Is this an issue? If so, is this issue fixable?
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Destination address(es) when redeeming an HTLC
Starting from this text at https://en.bitcoin.it/wiki/Script:
"The script for a typical Bitcoin transfer to destination Bitcoin address D simply encumbers future spending of the bitcoins with two ...
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