Linked Questions

1
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1answer
43 views

Bitcoin Blocks Date not coherent? [duplicate]

I was taking data from the BTC Blockchain with a custom script. I found something really weird. Block nr. 24668 was created at 2009-10-09 23:02:57 Block nr. 24669 was created at 2009-10-10 00:15:48 ...
33
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10answers
28k views

How to check if the block chain is up to date using bitcoind or json-rpc?

I read the full api method list and did not seem to find one. I suppose there is no command specifically for that purpose, so what is the general way of doing this? I would consider checking the ...
16
votes
5answers
2k views

What can xxxCoin do to stop the impending 51% attack?

Within the coming weeks both Namecoin and SolidCoin have been threatened with the same attack. What can be done by the users, pool operators and developers of these forks to either; A. Minimise ...
11
votes
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 ...
15
votes
1answer
2k views

What is the “zeitgeist attack”? Does it affect all blockchain technologies?

What exactly is this attack? It would be nice to have a good explanation of how it works and which chains can be effected by this. Does it apply to the bitcoin main chain, or only the newer and ...
4
votes
1answer
2k views

where do the timestamps on blocks come from?

A stork brings them... or... One of the basic principles on a dist. system is lack of a global clock. So how are the timestamps assigned to blocks, by the machine that mines it? Couldn't it just ...
3
votes
2answers
1k views

What security threats does blockchain technology solve or present?

I am interested in security, identity and authenticity in electronic networks. What sort of security concerns could blockchain technology help with and what sort does it pose? Are there entry and ...
5
votes
2answers
854 views

How could a time warp attack be prevented?

jarpian explains what a time warp attack (AKA zeitgeist attack) is: This is a 51% attack where the attacker sets the block timestamps artificially to lower the difficulty, allowing him to profit ...
2
votes
1answer
586 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 ...
1
vote
2answers
206 views

Bitcoin spend before received

When browsing the blockchain.info I came across this address. It seemed peculiar to me, that the amount of 0.6 BTCs has allegedly been spend before received. Is it because the "receiving transaction"...
1
vote
1answer
70 views

When is the halvening? What are the dates of past halvenings?

When a miner finds a new block, they receive a block reward that is comprised of the transaction fees from that block, plus a set amount of newly minted BTC. When the network started, this block ...
0
votes
1answer
62 views

Proving the margin of error of a block timestamp

In the Bitcoin wiki: Block times are accurate only to within an hour or two. is a bit vague. Is it possible to prove that an arbitrary accepted block timestamp is within x seconds of the real-...