Questions tagged [timestamp]

Collects questions about the rules, precision, and utility of the timestamp in block headers.

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1answer
52 views

How exactly is network time sampled?

How exactly is network time sampled? Is it as simple as one node stamping data right before being sent, the receiving node logging the current time before all other activity, and taking the ...
3
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1answer
641 views

Ripple ledger time format?

I am wondering what is the format used in Ripple ledger time? For example, one of the most recent ledgers had close_time of 447299110. I initially thought it was UNIX time, but the current time was ...
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3answers
1k views

How accurate is Bitcoin network time?

Have any observations been made to conclude the accuracy of Bitcoin network time? It would be interesting to know if NIST or any other authority has tracked the phenomenon.
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1answer
253 views

Can an old block be inserted into the blockchain?

I've been shown how network time is enforced, but I'm still having trouble understanding how a false old block cannot be inserted into the blockchain with the entire chain remined or how a powerful ...
3
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1answer
357 views

How is network time enforced?

I've seen how nodes gather network time data, but how is it enforced in the blockchain? Are all of the timestamps digitally signed and included in the block as proof?
2
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1answer
603 views

Are transactions verified in chronological order?

I've seen that blocks include timestamps which are updated "Every few seconds", but who updates the timestamps, and are the timestamps used to verify transactions in chronological order? If a block ...
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2answers
2k views

Are timestamps in transactions trustable?

I need to properly segment transactions by time. Are timestamps in transactions trustable? Can these be forged? I'm not sure if transaction timestamps are part of the protocol, but I'm particularly ...
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1answer
170 views

distinguish change address from real origin<->destination

a lot of bitcoin clients now send change address balances back to the origin address, by default, to make it easier for people to keep track of their balances. with this in mind, those transactions ...
0
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1answer
247 views

understanding timestamp from blockexplorer.com

What is the timestamp used for the blocks on blockexplorer.com For example block 233969 has: Time: 2013-04-30 23:27:36 is this time converted to 32bit hex for hash calculation, if so how ?
5
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2answers
2k views

Why the timestamp component of the block header?

What is the reason for the timestamp field in the block header? Surely the nonce should be the only property that changes? Should the nonce reset to 0 everytime the timestamp changes?
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2answers
924 views

Can a miner set the EXACT timestamp of a block?

I know that miners can adjust the timestamp of a block, but can they control the exact timestamp datetime (within the +-2h rule)? For example: A miner mines a block at 2013-08-08 08:01:34. Can the ...
2
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1answer
139 views

Bitcoin QT computer time

Bitcoin qt says my computer time needs to be correct for it to work properly. My time is right to the minute, but not the second. Will this cause a problem?
2
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3answers
141 views

Can the Bitcoin network be used as a timestamping service?

Does the Bitcoin protocol provide means to add some freely definable data to transactions such that a small transaction could actually be used to timestamp arbitrary data?
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3answers
4k views

What format is the time of a Bitcoin transaction stored in?

This may be a very simple question to answer, but I haven't been able to quickly find it. Regardless, if you were to deconstruct a transaction in the blockchain, and pull out the time value of the ...
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2answers
2k views

How does Bitcoin figure out what time it is?

Bitcoin needs to know the current time in order to validate blocks. How does it decide that? Note that I'm talking about the Satoshi client specifically.
7
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1answer
2k views

How is locktime enforced in the standard client?

I am trying to study the locktime feature of transactions ( https://en.bitcoin.it/wiki/Protocol_specification#tx ). I have created some raw transactions in the testnet with different locktimes, but, ...
1
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1answer
232 views

In a given contract, should the “LockTime” timestamp include an extra hour for confirmations to prevent a double spend?

Anytime a transaction has a timestamp attached to it, and there are signed but not submitted transactions at play, shouldn't the holder of the non-submitted tx have to take into account the ...
11
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2answers
4k views

Transactions with a wait time (using nLockTime)

I'd like to know if there are transactions that can only take place at some predefined moment. In principle, it should be possible to use the parameter nLockTime to wait for a particular block number: ...
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2answers
2k views

What stops miners/nodes lying about what time a block was mined?

From what I understand, the difficulty required by the proof-of-work in bitcoin is a function of block history, specifically the average time between last ~2000 blocks, with the intention that its ...
11
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5answers
3k views

how can I insert an arbitrary sha256 hash into the blockchain?

If I want to prove that I wrote a particular document before a certain point in time, it would be sufficient to generate the sha256 hash of the document and somehow arrange for that hash to appear in ...
12
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1answer
2k views

How can an earlier block have a later timestamp?

Block #180966 has a timestamp of 2012-05-20 23:02:53. Block #180967 has a timestamp of 2012-05-20 23:02:13. How has the software permitted a later block to have an earlier timestamp than its ...
18
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1answer
2k views

Was a timejacking attack ever performed?

The timejacking attack appears to be a pretty straightforward attack to pull off successfully. I was wondering, whether it was ever performed and documented somewhere, or was it just theoretically ...
5
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1answer
382 views

Getwork - can the miner increment timestamp?

When requesting getwork from bitcoind or a pool, the miner is expected to be incrementing the nonce value of the block, but can it also increment the timestamp value, or would such tempering cause a ...
10
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2answers
324 views

What are acausal blocks?

In this forum post the poster (2112) writes: It is my understanding that at least Eligius pool isn't a "honest node" and intentionally produces acausal blocks (or at least as close to ...
21
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1answer
816 views

Gaming the “off-by-one” bug (difficulty re-target based on 2015 instead of 2016 block time span)?

In this forum post from Gavin Andresen he writes: Second: I've written 'discourage blocks' infrastructure: https://github.com/gavinandresen/bitcoin-git/tree/discourageblocks (code reviews ...

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