Topic: delete - page 6. (Read 23927 times)

Someone must be gaming the difficulty.  Maybe the "pulsing attack" others have mentioned.

Difficulty adjusts ever 240 blocks (2 per day, 3 minute target block = 240 blocks per 12 hours).

I am showing 17873 blocks and difficulty of 2791
Initial difficulty was 8.

17873 / 240 = 74 adjustments (truncating the fraction)

The network has continually been behind the 3 minute target so every adjustment should be max upward.

If max adjust is 10%.  8 * 1.10^74 = 9205
If max adjust is 13%.  8 * 1.13^74 = 67,747
If max adjust is 15%.  8 * 1.15^74 = 248,159

Actual difficulty after 17873 blocks (74 adjustments) is 2791 (a mere 348x original difficulty).

What gives?

Yeah great gift. 99% of all generations were invalid for the first hours anyway. I think the difficulty was started too low.

And why start difficulty at 8 instead of, say, 1000? Well, gifts for all fanboys 24/7 on IRC ready to start mining from second 0.
You can't at the same time say you're spreading early coins amongst "thousands" of early adopters and be surprised that a difficulty of 8 gives super fast blocks.

My guess is the 'network requirements' are that every second block has to be signed by some king of magic private key. Of course that would be terrible design as the key will leak sooner or later but I can't think of any other way of getting trusted super nodes to contribute to the block chain in the way SC2 seems to have done.

so it sounds like difficulty is increasing as planned.  The problem was initial design having initial difficulty of 1.  And that doesn't seem like that much of a problem.  It does heavily favor whoever was mining for these initial low difficulty rates.  As throwing huge amounts of processing power at the chain would not increase difficulty heavily.

If the initial difficulty was 10, the difficulty right now would be 10x what it is now.  If it started at 100 it would be 100x what is now.  This was probably an unplanned problem due to the variables stated above.

The only problem I see with having the hard 10-15% difficulty increase cap is the chain does not adjust well to large amounts of processing power being added.  That coupled with the uneven % increases in the negative direction, and the "attack" mentioned a few posts back of strobing/throttling a large botnet onto the chain seem like it could become a problem.  Not so much a huge problem, just that a large amount of processing power could be used on the chain for a longer amount of time due to the retargetting scheme - which would mean potential attackers could "harvest" more out of the chain without affecting the difficulty as much.

I also don't think the huge # of stales at the start was an attack.  It more sounds like the extremely low difficulty of 1 coupled with a huge influx of unexpected miners caused a lot more problems than expected.  If you are generating a block every 1s - it's going to be real hard to keep the whole network on the same chain.  Propogation time alone of the blocks would probably take longer than generating a new block - and that was more the main issue it seems at the start of this chain.

As for central authority and % skimming of generated blocks that's a whole other issue not related to security, and more related to trust and design.  As people have been posting, that really is an issue with trust and with who controls that wallet.

Claims of 51% attack preventions - I don't believe there is enough evidence or proof here to refute or back up those claims.  But I'd be wary of assuming this is true without proof.  But I also wouldn't go out of my way to say it's not there.... There is no proof for either side to be true, just claims that their side is true....  Show me a 51% network control double spend and I'll believe it doesn't have protection, or show us/explain to us the code of how a 51% attack couldn't succeed.  But without proof on either side my bias would be to assume it isn't true because there's no gain, only potential loss by assuming it is true without proof.

edit: difficulty started at 8? or you could think of it as difficulty starting at 6.03 after first retarget?
6 * (1.13^69) = 27578.0688

Max adjustment upwards is 13%. Retarget occurs every 360 blocks. Difficulty started at 8 but the first retarget was actually down, to 6.03 if I remember rightly (due to the genesis block being generated quite far into the past).

That's actually pretty darn clever! He has created a trivial implementation of a vector clock. Basically the "trusted nodes" are really time keepers marking what happened in what order. I'm assuming they are known in number and non-anonymous nodes.

In the case of a network partitioning (intensional or otherwise) the known trusted nodes have to be partitioned as well. In this case, since you know the total number of trusted nodes, you have an additional piece of information to use in reconciling chain forks. The number of trusted nodes marking time on each fork. This defines the center of the SolidCoin universe.

If 90% of the trusted nodes are marking time on one fork, and you are hammering a fork with 10% of trusted nodes marking time, you will probably lose when the partitioned networks recombine. But fortunately, for you, that should become apparent as you see timekeepers drop off your chain.

Yup, the only thing broken in diff adjustment is its design. But otherwise it "works" as intended.

Yup.  In related news the US treasury is immune to 51% attack.

It's a hard sell for me reading this thread.  I'm not saying CH is out to scam anyone, but he is relying on blind trust of an anonymous internet user to back his claims... and to me that's just not enough....  Back up your claims of features, and they can be taken as features - otherwise it's just all talk.  Proof = backing, not talk

Do you mind if I ask what reason you have to place so much trust in CoinHunter/RealSolid?

Satoshi did not ask nor want that any trust be placed in him, the code was open from day one.

So hold on, let me get this straight, I'd like you to show me how % increase is working right now?

What's the difficulty right now?

Here's my calculation of 70 max adjustments starting from difficulty 1:
http://www.google.com/search?q=1*1.15^70

1 * 1.15^70 = 17735.72

so using max % adjustments for difficulty, difficulty should currently be at 17k difficulty.... what is it at right now?

So let's use the "max" as 10% instead:

1 * (1.10^70) = 789.746957

hrm... still 789 there... what's the difficulty right now?

unless someone is doing a massive strobing of hash power at each retarget, then I just don't see how the difficulty is correctly increasing...

someone correct my calculations, I don't know the exact state of things, just read through this thread

The sources will be published, just some more patience...

The trusted nodes are where the "51% proof" comes from.   Another name for them would be the central authority.
In theory anyone can be one if they meet the networks requirements, but CH/RS has ducked every time anyone asked what those are.

Ah, I see. For those wanting to do their own calculations, it would appear that only odd-numbered blocks are actually mined. Even-numbered blocks are created by some kind of trusted node or something and pay 3.2 SC to RealSolid's CPF in place of the usual generation payout.

There seems to be a flaw in the difficulty logic. (At least it seems like it to me.)

If as CoinHunter said, the difficult increases slowly in response to increases in MHash/s,
and the difficulty decreases quickly in response to decreases in MHash/s.

Then you have a different kind of 51% attack that people are not used to. If one were to "strobe" massive hashing power based upon difficulty increment periods. You could effectively reduce difficulty drastically, for a given fixed hashing power.

So in period A, the attacker goes full blast driving up difficulty 2X.
Then in period B, the attacker stops hashing totally.
If difficulty falls more than the previous 2X rise,
the new current difficulty will be lower than before the attack began.

Wash, rinse, repeat.

It's funny watching everybody fight while the Titanic sinks.

You talking to me, or to SC 2.0? 

For reference, Bitcoin difficulty increased by 1800% (~100k ->1.8m) between April-August, which took ~15 difficulty adjustments, while still maintaining rough target block generation.  SC 2.0 has yet to even reach target block generation after 70 adjustments - it's still only 1/17th of where it should be.

Rofl. Perfect.