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Coinotron pool has bigger than 50 percent hashrate on LTC.  You only need something like 50.000001% to be able to double spend

Coinotron mined 8 blocks in a row earlier today.  OKcoin only requires one confirmation per deposit, someone could double spend sell LTC buy BTC withdraw to exploit millions.

I suggest you look into what's called the '51% Attack' and 'Timewarp Exploit'. From what i've read, having over 50% of the network hash does not guarantee a successful attack, it only makes it more likely to be successful. Litecoin's fast block times also make it much less likely for the attack to be successful compared to BTC.

This is not cause for concern. Coinotron is a mining pool that deals with many currencies. A 51% attack on Litecoin would be disastrous for the pool's reputation, and Litecoin commerce is so rare that there is no real profit to be made from such an attack.

Malicious actors?


trade on exchange for other coins?

None of that is right.  With a majority of the hashpower an attacker has a mathematical certainty of generating the longest chain.  However an attacker would probably want a larger margin so there is more confidence over how long it takes for the attacker to come out ahead.  A faster blocktime does not reduce the chance of success.  A faster block time means a higher rate of orphans which means more of the legit miner's hashpower is wasted.   An attacker is not subject to orphans as the attacker will always build only of his own chain.

That being said an entity simply having a majority isn't a guarantee there will be an attack.

Cointron will never do that because if they do it, then it will heavily affect the price of litecoins, they will ultimately degrade the value of the coins they mine themselves, that would lead to their loss.

According to the site below, an attacker controlling 50% of Litecoin's network hash only has a 46.46% chance of a successful timewarp attack in 100 years. For Bitcoin, the same attack would take less than 1 day before it's successful. The more of the network hash an attacker controls, the more likely the attack is to be successful.


http://www.reddit.com/r/litecoin/comments/1cssqr/the_math_why_litecoin_is_more_secure_than_bitcoin/

The article uses some incorrect terms.  A 51% attack implies the attacker has a majority of the hashrate.  The article deals with situations where the attacker has a minority of the hashrate (and a very dubious example of exactly half the hashrate).  In that article every reference to "51% attack" should be replaced with "double spend".   You confuse the issue further by using the term timewarp attack which is one possible exploit for an attacker who has a majority of the hashrate.  Network halting, timewarp exploit, and double spending are all exploits that are possible when a malicious entity abuses a situation where it has a majority of the hashrate ("51% attack").

The math in the article while not wrong is misleading.  The article implies that for an attacker with <=50% of the hashrate to build a longer chain after one week would be very difficult.  Well no kidding.   For litecoin one block week is 24*24*7 = 4,032 blocks.   Yes with 4,032 confirmations one can be reasonably sure it is nearly impossible for an attacker with a minority of the hashrate to successful double spend that.  The key word is minority.  The comparison to Bitcoin is equally dubious because it compares a scenario where a Bitcoin tx has less confirmations  (1,008 vs 4,032).  Yes once again having 1,008 confirmations is less secure than having 4,032 confirmations when dealing with an attacker who has a minority of the hashrate.  The key word again is minority.

The bitcoin pdf has proper although simplistic math for the probability of double spending with a minority of the hashrate http://bitcoin.org/bitcoin.pdf.  Meni wrote a more comprehensive paper that deals specifically with the economics of double spends https://bitcoil.co.il/Doublespend.pdf.  If the attacker can maintain a majority of he hashrate then the success rate of a double spend is 100%.  No amount of confirmations can provide a confidence that the transaction can't be reversed.  The longer the attacker works on his chain the higher the probability that it will be longer than the "legit" chain.  For a short period of time the legit chain may remain ahead due to "good luck" but eventually the attacker will pull ahead.  Or stated another way, if the attacker has a majority of the hashrate then it is a mathematical certainty the attacker will eventually produce the longest chain.

coinotron was at 51% about an hour ago.. now it is at 50.2%

Even if its in coinotrons best interest not to fork or double spend, Who says hacker(s) that does have that interest cannot posion the pool to their advantage.

Edit 10 minutes later: now down to 49.8%

Agree. A few scenarios:

1. Hackers are able to get into Coinotron and fork.
2. They attack Coinotron's host. If they use any kind of hosted services, this is possible.
3. They attack DNS and redirect traffic to their "pool".
4. Attack another pool and take control. DDOS coinotron and hash gets redistibuted.
5. Nothing happens, we all get old. I have a beer.

If hackers could hack Coinotron, they'd have done so long ago and simply drained the wallet. Even that would be more profitable than a 51% attack on Litecoin. There is almost no place to double spend on with Litecoin, unlike with Bitcoin.

I agree the bad guys would have cleared out the wallet if they could. Coinotron is probably attacked daily by those attempting to get the wallet.

With 51% percent, attacking the stratum becomes a little more appealing. Coind, stratum, front-end, db are most likely on different servers with different amounts of security.

"no place to double spend". LOL-ed. trade for btc n run

the majority of altcoins have pools with well over 50% mining them and there have been very few attacks against any of them. I would say little to worry about.

I view it as quite the opposite: almost no coins at all are anywhere near secure, especially scrypt coins, even litecoin and DOGE.

This has been clear since DOGE did us all the favour of showing us all that litecoin, the highest hash power scrypt coin at the time, could be out-hashpowered just by some stupid meme almost overnight. By being that stupid meme, DOGE also made it clear that is itself is insanely insecure.

So all in all the whole scrypt field is garbage, the hash power so fragmented it is crazy to bother with any of them.

Maybe if litecoin and DOGE could be merged mined together there could be some hope, but they apparently prefer to continue to make a joke of the whole scrypt space.

-MarkM-

Coinotron are asking miners to leave to fix the 51% threat. Ghash had a similar situation a few months ago as well. Saw this on Reddit:
"Due to the Litecoin hashrate increase on the Coinotron mining pool, the cryptocurrency silver is now under the 51% threat.
Ghash.IO mining pool welcomes all the Litecoin miners to join our pool with the 0% pool fee and enjoy unique advantage of shared credentials with CEX.IO Bitcoin Crypto Exchange.

We encourage media resources and Litecoin adherents to help us in spreading the following message and save Litecoin together.”

link?

Famous last words of Cryptsy


I think it's VERY obvious we are about to see a massive scrypt holocaust and consolidation into LTC with other coins having hash rates similar to the sha space like peercoin.

LTC will have a network resembling that of BTC with all the same big pool players in on it such as KNC, Ghash, etc.

link?
[/quote]

.   http://www.reddit.com/r/litecoin/comments/264iio/let_us_save_litecoin_together_with_ghashio_pool/ (http://.   http://www.reddit.com/r/litecoin/comments/264iio/let_us_save_litecoin_together_with_ghashio_pool/)

.  https://litecointalk.org/index.php?topic=19820.msg171918#msg171918   (http://.  https://litecointalk.org/index.php?topic=19820.msg171918#msg171918)

Coinotron did NOT ASK anyone to leave.

Ghash.IO is just trying to get miners to move to their pool.

this is not healthy and not good whatever way you spin it

Heck, it's a great attempt with pushing a site. Nothing like nuanced promotion huh? (I'll be honest it gave me a chuckle.)

It would be nice though if pool operators provided responsible requests for people to mine on another reputable pool (but then you get into the whole thing about possible collusion and so forth).

Yes they may be of course they want more business, but all should be concerned about 51% situation on LTC.

Plus you are wrong in saying they are not asking miners to leave. Coinotron ARE asking miners to leave (just not doing a good job of it) read the Coinotron comments here on bitcointalk https://bitcointalk.org/index.php?topic=49182.msg6843591#msg6843591 (https://bitcointalk.org/index.php?topic=49182.msg6843591#msg6843591)

To quote Coinotron "I'm doing my best, trying to convince big LTC miners to diverse their hashrate"

Oh, did you receive an email from them? They have everyone's email address.

There are no messages on the front page.

Here’s a new LTC pool to use:
http://ltc.cryptoculture.net/index.php?page=register