TERRACOIN ATTACK OVER 1.2TH ATTACK CONFIRMD

[Trillium]

if the attacker has all these coins he wouldn't want the coin to die I guess, cause he'd lose all, wouldn't he?

You are assuming the motive of the attacker(s) is to make money.

[CoinBuzz]

how's the attack? is it over?

[No_2]

Can anybody give a small summary of what happened? Seems confusing at the moment. I have some TRCs and am wondering whether they will be worthless.

This seems to be the most concise explanation, crucially there are two things going on; the timewarp bug and the attacker currently has >50% hashing power on the TRC network:

Since TRC is based off the BTC source, is the 6 hour thing something BTC fixed previously that TRC never copied? Or is it a TRC-specific bug?

TRC not only didn't copy the fix, it made it worse.  Asymmetrical difficulty changes (where difficulty can go down more than it can go up) allows the attacker to amplify the effects of the attack.  No serious crypto-currency can have an asymmetrical difficulty system.  It is trivial to exploit.

[RoadTrain]

Halving removed, old times of dead blockchain back.

[Bogart]

I installed the 0.1.3-44 update, and it shows me at block 175200.

start your client with following parameter :

Code:

-reindex

(append it to your shortcut command), it should do the trick.

Did not work.  It got stuck reindexing 175009 (I assume that's where the chains diverge).

Deleting the chain and redownloading, it's now on 175038 like I hear it should be, but it still says "14 hours behind".

[RoadTrain]

Deleting the chain and redownloading, it's now on 175038 like I hear it should be, but it still says "14 hours behind".

I think it's OK. Client sees blocks from old chain but rejects them due to code changes. Users should upgrade their clients.

[roy7]

upd.
deleted all files (except wallet and conf.) in appdata
loaded only 175038 blocks on 0.1.3-44 client

Sounds correct then. 175038 is how many blocks we have at the moment. If the client says something like "of an estimated X" you can ignore that

The current block being worked on is difficulty 305K and we don't have a lot of hash power on the network. Sooner or later we'll get it solved though. Because when the exploit was closed there were so many fast blocks at low difficulties, the difficulty shot up quite quickly. Will need to do a few high difficulty blocks to get past the 'peak' and things should then lower back to pre-attack levels...

[roy7]

Next difficulties will be:

304455
348553
382574
404237
412645
408217
392442
367529
336037
300544

Is the difficulty adjustment not based at all on time since last block? I guess I was assuming with this block taking so long, it'd more quickly adjust back downwards. But I don't know how the EMA algorithm in TRC actually works.

[roy7]

So here's much of our problem, very low hash power.

Coinotron and Multipool have TRC suspended. If you add up the other 3 pools I know of (Hynodeva, Redpoint, RoyalMinindCo) that adds up to 39 GH/s.

P2Pool who is still on the forked chain has a "local rate" of 30Gh and a "pool rate" of 54Gh. So at the moment, p2pool is more than half of the total pooled hash power but they still haven't upgraded to new client and re-indexed.

An ASIC with 2x60G/h helped us reach block 175K and sent me a private message about doing so. I'll ask if he'll solve block 175039 for us, to keep things moving ever so slowly.

[roy7]

The large TRC-friendly ASIC just landed block 175039 for us. Hoping he stays around to kill a few more until diff drops.

[Mike270]

The large TRC-friendly ASIC just landed block 175039 for us. Hoping he stays around to kill a few more until diff drops.

That's nice but I guess that's gonna happen frequently from now on and afaik this was why they introduced the diff halving (that was now abused) in the first place... what's gonna save us when for example at one exchange prices rice dramatically, hash power increases accordingly, then prices drop & miners leave and we are stuck who-knows-where?
Does anybody know where such kind of discussions by the devs can be followed? On terracointalk.org there seems to be not much going on :-(

[roy7]

The large TRC-friendly ASIC just landed block 175039 for us. Hoping he stays around to kill a few more until diff drops.

That's nice but I guess that's gonna happen frequently from now on and afaik this was why they introduced the diff halving (that was now abused) in the first place... what's gonna save us when for example at one exchange prices rice dramatically, hash power increases accordingly, then prices drop & miners leave and we are stuck who-knows-where?
Does anybody know where such kind of discussions by the devs can be followed? On terracointalk.org there seems to be not much going on :-(

Looking at the github comments on the patches, I believe the difficulty halving was before the change to an EMA based difficulty algorithm. When that went into place, the halving should have been removed but wasn't, and the attacker found a way to exploit it. Once we're back to "normal" I'm not sure we need the halving.

Remember before attack the network had a lot of hash power on it, sometimes 500Gh or more, and difficulty worked fine to adjust up and down as people changed coins. None of that was using the halving code.

[Mike270]

The large TRC-friendly ASIC just landed block 175039 for us. Hoping he stays around to kill a few more until diff drops.

That's nice but I guess that's gonna happen frequently from now on and afaik this was why they introduced the diff halving (that was now abused) in the first place... what's gonna save us when for example at one exchange prices rice dramatically, hash power increases accordingly, then prices drop & miners leave and we are stuck who-knows-where?
Does anybody know where such kind of discussions by the devs can be followed? On terracointalk.org there seems to be not much going on :-(

Looking at the github comments on the patches, I believe the difficulty halving was before the change to an EMA based difficulty algorithm. When that went into place, the halving should have been removed but wasn't, and the attacker found a way to exploit it. Once we're back to "normal" I'm not sure we need the halving.

Remember before attack the network had a lot of hash power on it, sometimes 500Gh or more, and difficulty worked fine to adjust up and down as people changed coins. None of that was using the halving code.

No, they were using the halving code all along, I was monitoring it and you can see it by the fluctuations in the timestamps (+/- 20 mins).
Whenever a block was >5mins old, they'd make their client think it's actually 15 mins in the future ( so the client thinks the block is >20 mins old) to trigger the diff halving). It's difficult to see in the block explorers since they don't have the timestamp when they actually received the blocks, but when you see something like

block 1      10:10h       Diff 10000
block 2      10:30h       Diff 5000
block 3      10:11h       Diff 6000

then you can be pretty sure that the timewarp magic was used for block 2 whereas blocks 1+3 might be from regular miners.

Another scenario was when they found a block that was not yet 5 mins old (so they couldn't use their magic yet) they dated it 5 mins into the past, that way being able to mine the next block at half diff right from the beginning.

Something along

block 1    10:10h     Diff 10000
block 2    10:05h     Diff 12000
block 3    10:25h     Diff 5000
block 4    10:11h     Diff 6000

But they did it way better than the attacker from the last few days because they didn't take a 100% of the cake.
And also everybody else was profitting of the generally-low-difficulty as well, whereas last days' attacker was so fast almost everybody else was filling the orphanages.
But there were quite a few situations where we probably had been stuck for quite a while hadn't someone used the halve-diff trick for getting diff back down sooner than otherwise.

Kind regards
Mike

[bcp19]

Coinpolice shows TRC being on block 175,433 and 5k diff, does this mean they are out of date and on the old client?

[Mike270]

Coinpolice shows TRC being on block 175,433 and 5k diff, does this mean they are out of date and on the old client?

Yep

[roy7]

Coinpolice shows TRC being on block 175,433 and 5k diff, does this mean they are out of date and on the old client?

They'll need to upgrade and use -reindex once to get synced up.

As far as I know, only the mass of p2pool users (who have to all individually upgrade since it's decentralized) and BTC-E need to get synced in.

[bitcoinreactor]

i withdrew some TRC from BTC-e while we were at block 175038, and got my 1st confirmation with block 175039 so it looks like they're on the right chain.

[roy7]

i withdrew some TRC from BTC-e while we were at block 175038, and got my 1st confirmation with block 175039 so it looks like they're on the right chain.

Whew! Last night they were on the other one. Yay.

[Arbitrageur]

Next difficulties will be:

304455
348553
382574
404237
412645
408217
392442
367529
336037
300544

block 039 in fact has 304518 difficulty, so your calculation looks pretty much accurate, does that mean that we will have 1 block per day at this pace?

[roy7]

block 039 in fact has 304518 difficulty, so your calculation looks pretty much accurate, does that mean that we will have 1 block per day at this pace?

Depends on network hash power. There is a big ASIC helping us out on my pool right now:

8 miners @ 123.42GH/s are mining block 175040 with difficulty 351362. Avg time/block: 3h 24m

So to use 24 hours for an example, we should have roughly 7-8 blocks found, depending on luck of course. At current difficulty.

I have no idea how long our benevolent ASIC overlord will keep working on TRC though. Hopefully a while.