About 2.5 minute block targets
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FTC 2.5 minute block targets, What time is it determined? I think it was not initially identified, Who remembers ? :)
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yes, that was defined initially.
the difificulty is adjusted to archive the target timeframe of 2.5 minutes, if the hashrate varies and a deviation from that timeframe occurs.
there are always gaps but it works quite well :)
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The difficulty of the next transaction block to be added to the block chain is calculated by the wining miner of the last block.
For Feathercoin it is based on the Block rate over the last 126 blocks (cheers Wellenreiter).
The more miners there are, the higher the difficulty will be set, to maintain the block rate at 2.5 minutes.
An easy way to think of it is,
If one person is calculating 1 sum a minute and you want him to do 1 hours worth of sums, you give him 60 sums
If there are 2 people, you make the sums twice as hard.
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Actually it’s 126 blocks only after the 2nd hard fork, which also implemented damping to reduce the jumps in difficulty, that occured before.
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thank you in advance.But I still have some questions.
I find some record on http://explorer.feathercoin.com/chain/Feathercoin?hi=76050&count=100 . The interval between the two blocks is not 2.5 minutes,eg block number: 76037,76038,76039, they are 2013-09-03 21:44:23,2013-09-03 21:44:52,2013-09-03 21:45:12.
Intervals of less than 2.5 minutes,That is why ? -
I guess it could be the the hash rate went up very quickly before the Difficulty was adjusted making it possible to mine blocks much quicker.
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2.5 minutes is the target. the time vary for each search with an average of 2.5 minutes. so each period (2016 for Bitcoin and Litecoin, 126 now for Feathercoin) an average is calculated. and applied to adjust the difficulty to get the 2.5 minutes.
Bitcoin and Litecoin And Feathercoin at start had a basic formula. that can be simplified as (1+ (delta time deviation/target) )* difficulty = new difficulty. this works when you have a steady and small change in hashrate. (the % is limited by a min and a Max on ) so 2.4 minutes would give (1+(-0.1/2.5))*difficulty= 1.04*difficulty
so if time is lower the 2.5 minutes diff will increase and if more then 2.5 diff will decrease.
actual FTC to make change a bit slower for hash rate jump for coins hoppers (delta over 126 + delta over 504)/2*0.25 *difficulty this is done every 126 blocks.
so time between 2 blocks is mostly never exactly 2.5 minutes. But it always try to get to that number. if you get the average of last 1000-1500 blocks you will find we are pretty much on it. With LTC retarget to lower diff some hours ago we will have longer time and diff will go down a bit for next day. we should be around 2.5 minutes tomorrow and stable at 145-150 diff and in 2.5 days when LTC retarget again we will probably get pretty fast to 1-1.5 minutes and back to 175-180 difficulty shortly after :(
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That’s fine. I understand what you say.