\[DISCUSSION\] Difficulty handling strategies

zerodrama

We here at Feathercoin got attacked by hostile miners, for ideology or for future profits. Our response was to limit the difficulty jump, shorten the block retarget, and add ACP.
New coins get a ton of activity and then they are left holding the difficulty bag so to speak. Catcoin had to reduce to every block retarget, 36 block average, and limit the difficulty jumps to 12%.
Others are considering Kimoto’s Gravity Well.

I’m going to pull out an old proposal I made earlier for an anti-hostile, miner incentive cycling algorithm. It reacts quickly to sustained attacks, but also gives miners an incentive at the beginning of each retarget period.
We retarget every 126 blocks within a 504 block sampling period. The original version here did not include the limit in jumps so I’ll have to modify it. Also it needs to be a more general and simple function (in case wallets disagree what block they are at).
[font=courier][size=6pt]
diff_1 = diff_0 + 7/14 * (diff_0 * [(hashrate_1 - hashrate_0) / hashrate_0])[/size][/font][font=courier][size=6pt]
diff_2 = diff_1 + 5/12 * (diff_1 * [(hashrate_2 - hashrate_1) / hashrate_0])
[/size][/font][font=courier][size=6pt]diff_3 = diff_2 + 3/10 * (diff_2 * [(hashrate_3 - hashrate_2) / hashrate_0])
[/size][/font][font=courier][size=6pt]diff_4 = diff_3 + 1/ 8 * (diff_3 * [(hashrate_4 - hashrate_3) / hashrate_0])[/size][/font]

This is just a draft. I’ll update it further.

RIPPEDDRAGON

oh boy…this can of worms again… not your idea but the diff re-target discussion in general

wrapper

We are being attacked by a 10 GHash agent. We assume a manually switched multipool at hash change over.

Either that someone has 10 GHash of ASIC scrypt hardware already.

In the case of Bitcoin peer pressure was enough to prevent manipulation, do the multipool miner know they are being used to destroy the coins they might support?

Bitcoin and Litecoin are open to the same “attack”. As long as their hash rate keeps increasing they are OK, when it levels off, …

You have my interest…

I’m all up for progress. I do not fear change.

What do the other devs think?

This seems worth brainstorming.

Let the ultimate experiment continue…