Questions tagged [sequence]
32 questions
36
votes
2 answers
What is TxIn's sequence?
I'm currently trying to generate the genesis block with my code and I've stumbled upon the TxIn sequence field that is not explained in the Protocol Specification wiki page, nor does it seem to appear in the block explorer. What is the way the value…
ThePiachu
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12
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1 answer
What does the sequence in a transaction input mean?
Following a transaction input:
What is the meaning of the sequence number? What does the 4294967295 tell me?
Michael
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9
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2 answers
Why is the locktime set at transaction level while the sequence is set at input level?
Giacomo Zucco pointed out the oddity of there being one timelock field per transaction, but one sequence per input.
Even for the original use of determining the order of replacement, it would seem that only the maximum sequence is relevant in the…
Murch
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1 answer
What does the 'n' in nLockTime and nSequence stand for?
I know what nLockTime and nSequence do, but I'm just curious about where the 'n' comes from. Thanks
Darius
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6
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Sequence number semantics
Reading the following BIPs: 68, 112, 125, I got a few questions about the sematics of sequence numbers. As far as I understood, in version 1 transactions, sequence numbers have the following meaning:
If any input has a sequence less than…
Simone Bronzini
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5
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2 answers
What is transaction "finality"?
bitcoind IsFinalTx() as seen here checks the properties of a transaction in this order:
Is nLockTime exactly 0? That's final. return.
If it's not 0, is it below the current block height / time? If so, it's final. return.
Ensure that every tx input…
pinhead
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5
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What is an "insecure transaction type", as mentioned by Bitcoin Wallet for Android?
I am running Bitcoin Core v0.11.0.0-gd26f951 (64-bit) at home on Ubuntu, and have installed the Bitcoin Wallet for Android on my phone. I sent two transactions from home to my phone: First, Second. One had a very low fee and took days, so I sent…
Pepijn Schmitz
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5
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1 answer
Is my understanding of locktime correct?
I have been trying to understand locktimes and sequence numbers. I'm gradually building up a picture in my head based on code, code comments and info on the web. Rather than asking lots of questions, I am going to describe my understanding of how…
mulllhausen
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Is there any way to make an UTXO that cannot be spent until a certain block #?
In bitcoin, each transaction has an nLockTime integer to specify the earliest allowed block number/time that the transaction can be added to the blockchain. In addition, each transaction input has an nSequence integer that could theoretically be…
morsecoder
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Does `0 OP_CSV` force the spending transaction to signal BIP125 replacability?
If I send bitcoins to an output whose script will execute 0 OP_CHECKSEQUENCEVERIFY when it is spent, does that require the spender to set the BIP125 signal indicating that the transaction is replacable?
For example, in cases where participants in a…
David A. Harding
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3
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What is the recommended sequence for signalling RBF?
What is the recommended nSequence for signalling RBF transactions?
BIP125 says:
A transaction is considered to have opted in to allowing replacement of itself if any of its inputs have an nSequence number less than (0xffffffff - 1).
What is the…
Karel Bílek
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2
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Sequence valid before time
I'm studying sequence, and I set a transaction valid after 512 seconds.
First of all I use regtest and I start from clean blockchain, after that I mine 114 blocks.
At this point miner creates a transaction and tries to send it
My decode…
monkeyUser
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In Lightning commitment transactions, what do the upper 8 bits of sequence and locktime represent?
In Bolt 3 of the Lightning Network specs, for commitment transactions it states:
locktime: upper 8 bits are 0x20, lower 24 bits are the lower 24 bits of the obscured commitment number.
sequence: upper 8 bits are 0x80, lower 24 bits are upper 24…
Darius
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2
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Why mark a transaction as RBF (Replace-by-Fee) explicitly?
I could broadcast a second transaction that has the same inputs but a higher fee, without marking the original transaction as replaceable. Miners would most likely favor the second transaction and reject the original one. Why should I mark my…
KayO
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2
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What is the "sequence" and its details as referenced for the segwit application?
On the segwit page there is a reference that the "feffffff" is the "sequence". What does the "sequence" represent in relation to what? Does it always have to be "feffffff"? What happens if it's "feffffff" instead of "ffffffff"? Does it help…
Mine
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