Is Terracoin's design flawed?

[celkaris]

diff already starting to increase..

[jar]

The difficulty is now increasing. It should be a buttery smooth transition. Everyone relax  

[evilpete]

A short (30) difficulty recalculation with a 2-minute block target is fatally flawed.  Terracoin is going to have to deal with this.

There's a reason why bitcoin is at a 2 week recalculation.  It is the forked blockchain resilience protection.  For terracoin, 2 minutes x 30 blocks is a really short window to create a viable forked blockchain.

Consider the v1/v2 bitcoin blockchain event a few weeks ago.  It happened about 1/4 of the way into the 2 week recalculation cycle.  Suppose a couple of fringe miners decided to reject v2 blocks and go it alone..  The v1-only block fork now has to mine something like 1500 blocks at 1% of the original hashing capacity to reach the difficulty adjustment.  Instead of being 10 days away, it is now 1000+ days away (3+ years) at their hash rate.  This is a long time to hold out in order to get the difficulty drop.  So far in the future there's no chance that a fork like this could cause significant trouble to the main chain's network.

But imagine if it was 10 blocks to recalculate (calculated at 60 per retarget minutes like terracoin)..  the v1 miners managed to find two v1 blocks in a row just moments after the threshold was reached.   On average they'd need to find just a few more blocks until suddenly their difficulty rate goes down and then start injecting them into the main chain network.  If they got lucky they might even be able to get a few blocks ahead of the main chain.

Imagine the 0.6 and 0.7.0/0.7.1 clients suddenly following the v1 block chain (which is now longer, and they don't care about v1 vs v2). and 0.7.2+ following the other chain.

Long difficulty adjustment is a feature. It is there to allow the network to make sure an attempted fork never gets off the ground with a pre-populated blockchain.  Rapid difficulty response is asking for trouble.  And it's not the oscillation in difficulty that's the problem, but loss of anti-fork protection.

[conspirosphere.tk]

I don't think the price will remain as high as it is. Those huge miners want BTC and they are going to dump a few k on the market pretty quickly i imagine.

At this price I already dumped all I could and I keep dumping as I mine, but I will buy back all and more when the bubble deflates

[mr_random]

Terracoin is going to have an interesting price graph that is for sure.

[celkaris]

A short (30) difficulty recalculation with a 2-minute block target is fatally flawed.  Terracoin is going to have to deal with this.

There's a reason why bitcoin is at a 2 week recalculation.  It is the forked blockchain resilience protection.  For terracoin, 2 minutes x 30 blocks is a really short window to create a viable forked blockchain.

Consider the v1/v2 bitcoin blockchain event a few weeks ago.  It happened about 1/4 of the way into the 2 week recalculation cycle.  Suppose a couple of fringe miners decided to reject v2 blocks and go it alone..  The v1-only block fork now has to mine something like 1500 blocks at 1% of the original hashing capacity to reach the difficulty adjustment.  Instead of being 10 days away, it is now 1000+ days away (3+ years) at their hash rate.  This is a long time to hold out in order to get the difficulty drop.  So far in the future there's no chance that a fork like this could cause significant trouble to the main chain's network.

But imagine if it was 10 blocks to recalculate (calculated at 60 per retarget minutes like terracoin)..  the v1 miners managed to find two v1 blocks in a row just moments after the threshold was reached.   On average they'd need to find just a few more blocks until suddenly their difficulty rate goes down and then start injecting them into the main chain network.  If they got lucky they might even be able to get a few blocks ahead of the main chain.

Imagine the 0.6 and 0.7.0/0.7.1 clients suddenly following the v1 block chain (which is now longer, and they don't care about v1 vs v2). and 0.7.2+ following the other chain.

Long difficulty adjustment is a feature. It is there to allow the network to make sure an attempted fork never gets off the ground with a pre-populated blockchain.  Rapid difficulty response is asking for trouble.  And it's not the oscillation in difficulty that's the problem, but loss of anti-fork protection.

you're comparing two distinct networks here (as in hashrate).

If you were able to mine blocks with 10x times more hashpower than the total btc network, the same problem would exist ; this is exactly what we see with the trc network (10x times "nominal" hashpower increase occurs multiple times a day).

If you had 10x the total btc hashrate in your hands, you could possibly forge the 2016 blocks in less than 2 days, then publish your longest chain.

Bitcoin did not ran into this because it was popular enough (by beeing widespread / early adopted) before huge farms / dedicated hardware came up

[jar]

Evilpete,

I believe what you describe has the same chance of occurring as a 51% attack. With the improved strength recently, this is less likely. Also, anyone that pulls this off will make their mined coins worthless so there is little incentive. It would only be done for the lols.

[jar]

I don't think the price will remain as high as it is. Those huge miners want BTC and they are going to dump a few k on the market pretty quickly i imagine.

At this price I already dumped all I could and I keep dumping as I mine, but I will buy back all and more when the bubble deflates

Once listed on btc-e, the price will increase further. I'm bullish. But im glad youre happy with terracoin and obviously others are happy to swap.

[celkaris]

the bitcoin old client db problem (introduced by newer 0.8.x builds) was solved without any satoshi/btc software release just because bitcoin isn't decentralized anymore ; dev "just" asked the biggest pool operators to downgrade their daemons to the right version, so the fork occured, letting bugged 0.8.x versions alone on a shortest chain

Later, the bugged 0.8.x build was updated, so miners (non-pool operators, more precisely) aren't affected anymore.

[celkaris]

the first difficulty "downramp" will be hard as hell... (when those big miners jumped off)...

[jar]

the first difficulty "downramp" will be hard as hell... (when those big miners jumped off)...

I don't think the network will behave like that. Difficulty transitions will be silky smooth over time unlike things were last week. We will see how it plays out but I am pretty certain there will be less chain hopping. At some point on the difficulty curve, big miners will see it as profitable. When they jump on the terracoin network, there wont be such a big difficulty shock and miners wont notice it for several adjustments.

[celkaris]

the first difficulty "downramp" will be hard as hell... (when those big miners jumped off)...

I don't think the network will behave like that. Difficulty transitions will be silky smooth over time unlike things were last week. We will see how it plays out but I am pretty certain there will be less chain hopping. At some point on the difficulty curve, big miners will see it as profitable. When they jump on the terracoin network, there wont be such a big difficulty shock and miners wont notice it for several adjustments.

With the massive hashrate spike, that had to happen, we now have to keep mining without those big miners for a while, then diff may eventually stabilize, hoping those big boys won't bring gigantic hashpower to the network this time (if many miners keep mining trc, diff should eventually stop bumping around)

[SalvorHardin]

I have seen the estimated hash rate of TRC network going from 4.5 Tera hash/second to less than 200 Giga hash/second over the last 10 hours.  Similarly, in the last 10 hours, the difficulty has gone from 2000+ to nearly 60000 now, with blocks being solved every 30 seconds to no block being solved during an entire hour.  Surely someone is directing huge amount of hash power in and out of TRC network.  Is this the "intended" and "expected" performance of TRC network given the recent obligatory TRC client fix/update?

[celkaris]

I have seen the estimated hash rate of TRC network going from 4.5 Tera hash/second to less than 200 Giga hash/second over the last 10 hours.  Similarly, in the last 10 hours, the difficulty has gone from 2000+ to nearly 60000 now, with blocks being solved every 30 seconds to no block being solved during an entire hour.  Surely someone is directing huge amount of hash power in and out of TRC network.  Is this the "intended" and "expected" performance of TRC network given the recent obligatory TRC client fix/update?

with 10x or 100x times more hashpower than the regular/usual network hashrate, i'm affraid there's no real fix until the network gets a bigger intrinsic hashrate... bitcoin itself would also be affected by those 10x or 100x hashrate increase, in a similar way

[celkaris]

i'd say we now have 2 or 3 hours until diff starts to fall again, probably less than the previous one, but who knows ... switching some miners to trc, i won't miss this train this time