Bitcoin Forum

I'm probably just missing something completely obvious, but why is it that blocks are being found what looks like out of order?

https://i.imgur.com/oWxXoHu.png

If you look at the image I took from a block explorer, how was block 336404 found before 336403? Same thing happened with blocks 336402 and 336401.

I have seen it some times but I have never known why that happens

Agreed. I have seen this with Blockchain.info's blockexplorer as well.
Its either an error with the block explorer, or the block was actually found first, but transmitted through the network in a weird way, thus late..

But I really don't know.

There is no way to synchronize time in a trustless way so timestamps don't mean a lot. One of the miners probably has their time set incorrectly.

The block height is the "order" that the blocks are found.  It is impossible for that to be "out of order", since that defines the order.

The timestamps are set by the miner, and can be off by as much as a couple of hours depending on various factors.

Therefore, the timestamps just give a general idea of when the block was solved.  It is sufficient for determining the new difficulty after 2016 blocks, but isn't usefull for determining exactly when a block was first broadcast.

Out of order? You're out of order! The whole trial is out of order! [indicates the gallery which is up in arms by this point] They're out of order!

























 ;D

i don't get it. How was it out of order?

Read quote #5. Skip quote #6 :P

Thanks! The thread title was poor, should have said something like block timestamps out of order. I knew that the height was the correct order (like a linked-list, right?). The timestamps were throwing me off. I was assuming the timestamp was being relayed in UTC from all the nodes when the block was found. But I guess it makes sense that any given miner (or pool) could have a bogus time settings causing issues.

I appreciate the quick answers to my question!

if only this forum allowed tipping...

The timestamp that any block explorer displays when a block is found is only the time that their node first receives "notification" of the block. It is not uncommon for a transaction (including a coinbase transaction of a found block) to propagate entirely through the network.

It is generally a good idea for any miner to use a very well connected node so it can quickly be "notified" of a newly found block

Block explorer probably had a small error. Aswell as Blockchain they shouldn't be used as to 100% to interpret the data and should be used as a guide only.

I haven't seen the source code for the various block explorers, but it seems odd that they would display something other than the block's timestamp. Are you sure you know what you are talking about?



It's generally a good idea to read the thread before responding to it.

The node that mined that block had a wrong time set, thus it signed the block with the wrong time and transmitted it through the network.

that makes sense

I have seen it some times but didn't know why