Quote from: boba02 on April 25, 2014, 09:48:50 PM

Guys, look what I found this morning. There were some speculations about Vertcoin's instamine, but the article I found explains perfectly how it was done and how big was the instamine.
I have a link on my other PC, so if anybody's interested I'll find and post it later.
My respects to the author, he/she did amazing job researching this.
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Dark side of Vertcoin - huge instamine uncovered!

What is Vertcoin?
Vertcoin is a cryptographic currency, similar to Bitcoin and Litecoin, with one major difference.
...

Premine - None
There is no premine except three, normal blocks done to test the network (150 coins). You can use the block explorer below to look them up. Unlike many other coins, no one has received a large amount of free coins to dump on an exchange.

(Vertcoin Official Announcement @ BitCoinTalk)

Every day there is a new coin launched and both miners and investors have one mutual concern - whether the coin has any premine or instamine. I guess we all understand why they are so concerned - nobody wants the price to fall down when high volume of premined coins is thrown to exchange markets.

In order to be honest with their communities development teams do public announcements. They claim how big is the premine and how they are going to spend it. This information can be verified if you go through coin's blockchain and track where the coins have settled down. Needless to say, some people try to avoid premined crypto currencies to eliminate risks mentioned above.

On the other hand, can you feel safe if you invest into a currency with no premine or instamine? Well, let's find out by using Vertoin's blockchain as an example.

As our epigraph suggests, "no one has received a large amount of free coins". Take a look at blocks from ~800 to ~4000 and list of the addresses these blocks' rewards finally went to.

Most of them fall into the same pattern:

- 20-25 blocks were mined in the range from 800 to 4000 (but some of them kept on mining significantly longer, till the next day) and went to one of addresses listed below
- mining started at ~09:38 and stopped at ~11:10-11:25 (officially Vertcoin was launched at 09:00) with a second group continuing to mine till the next day.

Some addresses of miners (stopped at ~11:10):

VpRfQx8kqfmgCwhAG9XNSK8eshmaKHc2qP
VwUin6isHk8BtXoq6WhKSCWPghuRtGQNjX
Ve9q5pe83HmBwLSFGa1ccb8hNSJKqVh2jP
Vk6weTvePCQk5WARu7drRhraV4ewmcnTNi
Vb989m8Ht9TxJ5mXYvs5fscoXpAc8EyPJp
VaALivNWCFSogd2gBqxXhvZotwt7oRaPcx
VsXNarZrg1PSjz7EAQRAoY7aQ7yEDfZoCS

Some addresses of miners (mined longer, but started at the same time):

VhwEtDZkgnBFPhUwnYfutayvoFGdEtQeMh
ViVLVLEFty8cMAZxo6erjAWiQFFNi594rC
VmJazUBfgUTGQJeTzeDEgYtX1GSXJLZThm
VuhteNHxA2sdkVVMCEoG1QjzeBe6DWgNQA
Vf5MNH8WzUCG2LnRWASyfxySiBevSeCrHy

That is to say, more than 100 "miners" started at the same time with one group stopped after ~2 hours of mining and the second one mined till the beginning of the next day. Let's take a look where the proceeds from these miners went to. It turned out that all of these blocks had finally consolidated into just 7 addresses (txid, consolidation times, blocks and amounts):

Miners stopped at ~11:10:

Vk7MDD1QYsTYZhByLK87c9BgfqRQbHgTPL

fb344cf9e6e05bb73e74d7a5ab6045d9bb67037b5042f65a831d4b7b0ba5d991 2014-01-14 04:33:48 (block 14052) and ae555bd88a476d3f6b469e424e758be9e551f216b0121d4c180646fc671ea08b 2014-01-14 05:12:47 (block 14115) 20,000 VTC + 20,000.00 VTC = 40,000.00 VTC;

Vq55c7qHcqhJdkb8FtSznRjFro4kkmyaxL

0832af79f1704f5b0ecf5c9caa56c62e2d5c41c392727a7561ee02578dd4b231 2014-01-15 19:20:53 (block 15404) 20,000.00 VTC - 250.08 VTC (not from miners) + 0.059 VTC (has gone to another address) = 19,749.98 VTC; this address also received 10,000 VTC in the same block at the same time from other sources, not related to this group of miners;

VfRTMtCBxrLYbvrzBxBSyMqZ5Hxyw53A6E

5ad063f930777b0225e726acf5d25b87c92e5c9754ee67112237508cc3609ce2 2014-01-18 05:15:46 (block 16842) 28,691.34 VTC - 23,736.42 VTC (not from miners, see details below) - 304.93 (not from miners) = 4,649.99 VTC;

Tracing of 10'000 VTC and 23'736.42 VTC amounts leads to address VjzovdCX2N4GuFB7S1fFshNCysHoe5xeAo (33,736.42 come in 14703 block and has gone in 15404 block) and further to a group of 5 addresses with one of them being mentioned above Vk7MDD1QYsTYZhByLK87c9BgfqRQbHgTPL (sent 20'000.00 VTC back); we can't count these amounts and addresses.

Miners stopped at midnight or next day:

VjyKAFZdjX8x1Qw29uMvzVi3hgznEPguYM

f3120115e06849d162f04d4e596af04a3181566b1502e2bad2c17788cc474b13 2014-01-23 08:22:04 (block 21477) 15,000.00 VTC - 4,400.00 VTC (not from miners) = 10,600.00 VTC

VsNY9jCKa9LcsHTEmvcLSiRoTopTm6Tvtm

00464b001bef6dcc5c99a6977f1c919d697ee09111f7e4a20d27154210ab690c 2014-01-24 17:16:02 (block 22794) 10,000.00 VTC - 2,150.00 VTC (not from miners) + 49.98 VTC (had gone to another address) = 7,899.98 VTC

VbU6RMMPN9Pa5npN9RPHQgghn2971qvvW4

88ba44fbc8327f227a93a650eb313c45a4d36d6a270e0b9b13f82c2e6313487c 2014-02-03 07:54:00 (block 28425) 20'000.00 VTC - 1,349.98 VTC (not from miners) + 49.94 VTC (has gone to another address) = 18,699.96 VTC

VwMCw4v5RBUtR2hjLhjRL219DPZ5gXNBTr

db9cf98506c40a26bcebb27631e9f8006e500a56b9f8179977d87a68f70ad2a7 2014-02-05 18:07:51 (block 30121) 9,999.00 VTC - 49.00 VTC (not from miners) + 0.91 VTC (had gone to another address) = 9,950.91 VTC

With a total amount of 111,550.81 VTC (these are the proceeds from the miners under our consideration, not counting other sources).

It's obvious that all of these coins were mined by one person or group of persons who know each other. Who was it?

The answer is simple when you figure out how that mining was done. There was a large number of preconfigured miners started at the same time. Most likely some cloud service was involved with huge number of VPS servers started from a template at the same time (please note that Vertcoin was a CPU-only coin at the very beginning). DigitalOcean isn't under consideration for two reasons: each and every VPS should be started manually, and there is a limit of total number of VPSes. Most likely, Amazon AWS EC2 instances have been used (or similar cloud provider). With Amazon AWS EC2 it's possible to start large number of instances from a single template, there are also some limits imposed to the number of instances, but it's possible to raise them in advance by the means of request to the support, and it's also possible to use multiple accounts and launch instances sharing the same template (AMI snapshot) from different accounts. If that's not enough, there are multiple locations available with their own limits. So, one should do the following:

1. Launch an instance.
2. Download sources of Vertcoin and sources of Vertcoin miner (vertcoind can be used for mining as well).
3. Compile vertcoind.
4. Install and preconfigure it.
5. Compile and preconfigure miner.
6. Take an AMI snapshot from this instance.
7. Submit a request to support to raise limits for number of instances. Wait 2-3 days for a reply. If that's not enough, distribute AMI snapshot to different regions, ask friends to create multiple Amazon accounts using their credit cards and give them access to the snapshot. Most likely, some kind of combination of methods had been used, taking into consideration that most of the instances have been started almost at the same time.
8. Launch 100+ instances.
9. Wait for them to load and start mining.

Is it possible to complete all of these steps within 38-40 minutes from a launch? Very unlikely. Conclusion: it was an insider from Vertcoin team who mined at least 111,550 VTC (0.13% of the total volume) shortly after the launch.

Now, when instamine is uncovered, what should we do with this knowledge? We don't know if the owner(s) still have it waiting for a better moment to do a huge sell. Or they already sold it and are not too concerned about VTC's future price.

That is why the only thing we should do is to accept the fact and keep going. Mine, trade and support.

From block 10 to 10000, it took just 17 hours. Normally, it should take 17 days.

That is huge instant mine, 24 times than it should be.

Height: 10
Version: 2
Transaction Merkle Root: f7aca21eb94c2a2427374c9f4af58b7aca525e7f2c376b6563652f3c2c2c823b
Time: 1389430919 (2014-01-11 09:01:59)
Difficulty: 0.000 (Bits: 1e0ffff0)
Cumulative Difficulty: 0.002

Height: 10000
Version: 2
Transaction Merkle Root: 4990d0c851c6e91676033f87d4319db91e8d3e072d4a5443aab92e4cc9379150
Time: 1389493124 (2014-01-12 02:18:44)
Difficulty: 0.038 (Bits: 1d1a2c60)