Dash is also under attack by computing power? Who will protect the PoW blockchain?

Dash (DASH) is a decentralized encrypted digital currency, which is rewritten based on the source code of Bitcoin. Its instant payment technology and good anonymity have made it quickly popular in the cryptocurrency circle. In addition, Dash master nodes can give investors 10%+ annual rebates and vote on monthly budget proposals.

But at the same time, the security of such a blockchain system based on the PoW consensus mechanism is as thin as a cicada's wing and may be attacked at any time. Simply put, when the computing power decreases, the PoW blockchain will be exposed to the risk of "51% computing power attack mechanism"!

The creator of Dash, Evan Duffield, and his "core team" of nearly 20 people are also aware of this risk and are working tirelessly to design a defense mechanism called Chainlocks. The Ethereum Classic blockchain, which recently suffered a 51% computing power attack, is discussing a defense algorithm, and BCHABC also has a similar mechanism.

It seemed to be a race against time to defuse the bomb before the fuse burned out.

In fact, during the period after the ETC double-spending attack, a lot of discussions about computing power attacks were rampant. For example, a netizen on the Reddit forum posted such a hot post, which quickly attracted heated discussions from countless netizens. His general meaning was:

At present, the computing power of Dash is seriously concentrated in NiceHash (the world's largest cryptocurrency mining computing power market). If Dash does not launch its long-designed security mechanism Chainlocks as soon as possible, a "51% attack" against Dash will soon appear! Operators of Dash-related services should be careful!

As for what exactly is a “51% attack”? And how does the “Chainlocks” defense mechanism work?

The warning letter from a user on the Reddit forum reads:

The following is the translation of the most discussed original post on Reddit:

Let me get straight to the point and prove some points first.

I happened to discover some truth about the ETC 51% computing power attack. Specifically, Nicehash has become the dominant player and has the ability to subvert the basic security of the blockchain!

Because, Nicehash currently has 70% of DASH's total hashrate. You can see the relevant data comparison through this link. (Nicehash has 1390 TH, while the total hashrate is 1790 TH).

This is the first problem I want to talk about. It is too unusual. Generally speaking, Nicehash has 10% to 20% of the computing power of Pow tokens, which has already posed a security threat to some smaller forked coins among PoW tokens.

The above is just the first question discussed.

The second question is: we should check the mining pools. If the computing power is directed to some well-known and trusted mining pools, this is not a problem. But unfortunately, the opposite is true. This website reveals that out of 1790TH/S computing power, only 560TH/S comes from a more reputable mining pool, and the rest of the computing power comes from some unknown places, which is also extremely unusual.

The Dash Explorer website shows which addresses are producing mining rewards. You can see above that there are four unknown "big guys" collecting all the unknown computing power. I used this block exploration tool (https://dashradar.com/explorer/tx/31de30b48c9263544724c0e607a9cb1f7bf05dc2961119827c52571334506172) This very special transaction contains three of the above four addresses, which means that in fact these three mining pools that are constantly collecting computing power are actually controlled by an entity (or organization, or group, or individual) lurking in the "darkness". This is not the most fatal, the most worrying thing is: these three mining pools have 53% or more computing power. The three addresses are:

XbUutDsgJbf7Sjjq4omhusNtkT8ih1d7oQ

XkNPrBSJtrHZUvUqb3JF4g5rMB3uzaJfEL

XeMPcKeVDN9bkECGDC7ggtf9QsX5thgKAx

These three mining pool addresses started to accumulate computing power half a year ago, that is, in September last year, and I think the fourth mining pool also belongs to this entity hidden in the dark , even if it is independent of this blockchain, because it also started to collect computing power crazily at almost the same time.

What conclusion can we draw from this? There is only one conclusion:

*ASICs are the cancer of blockchains. Or, to be more conservative, any coin smaller than BTC. They are not secure at all and are not comparable to the networks we are familiar with today.*

To be more specific: Nicehash is also a cancer cell. As long as one person is willing, he can immediately buy a large amount of computing power for DASH, and as long as he reaches 51%, he can do whatever he wants.

No matter who owns these mining pools, the DASH they mine will never stay in their hands for a second. It can be said that in the next second, you can see them on the exchange.

Therefore, when DASH configured its own Chainlocks, someone had actually prepared for the "51% hashrate attack". If you want to do it, you can start now. Anyone who provides services related to DASH must not let down their guard. As long as it does not make corresponding adjustments and further risk remediation measures, it must not be taken lightly.

After this post was posted, it caused a huge uproar. Many friends responded like this:

A friend named Zoden said: "Whether it is Dash or ETC, they are both well-known tokens ranked in the top 20. If they are all conquered, then the day when Bitcoin will be destroyed is not far away, and the entire cryptocurrency circle will be finished !"

A person named tranceology3 responded to the above point with a sarcastic remark: " POW is going to be finished, thank you! "

Savik519 said: “ I think we are going to see a 51% attack soon. In the near future, more and more tokens will be exposed to risks. ”

Dash official response to 51% hashrate attack

Is Dash's algorithm really as stated in the post, can it be bought with money? Will DASH really encounter the 51% computing power attack problem?

First of all, we need to make clear a fact: Dash currently uses the X11 algorithm, and if you want to mine, the only sensible way is to use ASIC mining machines.

So almost all mining machines are currently running at full capacity to mine Dash, and there is no idle computing power resources. Of course, you can buy a small part of the computing power, but you can't buy much unless you are completely rich. No one is stupid enough to use their AISC chip to attack the entire cryptocurrency chain, especially like Dash, where only smaller tokens are more likely to be at risk.

To sum it up in one sentence: It is feasible in theory, but extremely difficult to implement in reality.

In response to netizens’ questions, the Dash team quickly responded in the Telegram group:

The administrator said: Dash has encountered such doubts and challenges hundreds of times in its five years of development, but nothing has happened.

Dramatic speculation is rampant, and in fact, Dash’s Chainlocks will launch v0.13 in a few days, and v0.14 will follow shortly after !

Can Chainlocks keep blockchain secure?

The various objects of discussion above are actually two: What we just discussed is the potential security risks of network attacks, that is, the "spear" of "51% computing power attack", so what about the "shield" Chainlocks that everyone is talking about and looking forward to?

Alexander Block, a core developer of Dash, gave a very detailed technical explanation on the official Dash blog:

The emergence of the concept of Long Living Masternode Quorums (LLMQs) enables the implementation of a new protection mechanism against 51% mining attacks. This protection mechanism is called ChainLocks.

ChainLocks is a verifiable network-wide measurement/vote based on the "first seen" rule. Each block selects a LLMQ consisting of several hundred master nodes, and each participating member selects the chain that is active at the current height to sign the first block. If enough members (e.g. >= 60%) see the same first block, they can create a P2P message (CLSIG) to propagate it to all nodes in the network.

The presence of a valid CLSIG message indicates that a majority of LLMQ members (e.g. 60%) have seen the specified block as the first block. Since LLMQ is composed randomly from Dash's masternode set (currently about 4,900 nodes), the nodes that first saw this block in the network are statistically the same as those inside LLMQ. This means that if 60% of LLMQ members saw the block first, then about 60% of the network should also have seen it first.

If a node receives a valid CLSIG message, it should reject all blocks at the same height that do not match the specified block in the CLSIG message. This makes the decision on the active chain fast, simple and clear. It makes forks under this block impossible, and also makes 51% computing power attacks impossible. The blockchain network sees blocks that do not meet the regulations and directly rejects them, maintaining the unity of the main network.

The most important impact for ordinary users and merchants is that once a block protected by ChainLocks is confirmed on the chain for the first time, the transaction is considered confirmed. Since it is impossible to reorganize signed/locked blocks, transactions cannot be erased from the chain.

This also has an impact on mining economics, removing any incentive for miners to fork the chain. Attacks based on private or individual mining become impossible, as these attacks rely on miners withholding their private chain for a long period of time.

Who will protect the security of PoW blockchain?

Dash seems to have a protection plan, but what about other chains?

The problem of ETC seems to have been discovered three years ago, but it has not been solved. As early as August 2016 (a week after the hard fork of ETH and ETC), ETHNews reporter Brianne Rivlin published an article saying that a mining pool called 51Pool was preparing to launch a 51% computing power attack to destroy the ETC blockchain, but this did not happen.

But what was coming has finally come. Now that ETC’s 51% computing power attack has occurred , the ETC team has given the following solutions: develop an early warning plan, recommend that users wait for 2500-5000 block confirmations, wait for ETH to upgrade to the PoS algorithm before the computing power comes to ETC, and adopt the Keccack256 algorithm to prevent mining machine computing power .

Among them, the first solution has not yet been finalized, the second solution is for users to protect themselves, and the third solution is to wait for ETH to switch to PoS, and then the computing power will increase after it comes to ETC, so that the difficulty of 51% computing power attack will increase. The last solution has actually been cracked because there are already mining machines with Keccack256 algorithm on the market.

The most famous one is the BCH hard fork, which caused asset security issues and huge fluctuations in asset value for BCH users for nearly half a month. Similarly, BCH ABC and BCH SV have faced the threat of computing power attacks from each other . In the November client update, the ABC team added the checkpoints function to prevent SV from reorganizing the blocks.

As early as 2010, when Satoshi Nakamoto released Bitcoin version 0.3.2, he mentioned that "adding checkpoints can play a security role. Even if someone has more than 50% of the computing power, he cannot go back to yesterday to reverse the blockchain."

A 51% computing power attack seems to be a problem faced by almost all PoW blockchains that have lost computing power and users. We hope that developers can solve these problems, but we find that developers in this world lack certainty and can fork and do something else with just a "disagreement".

If we don’t rely on the community or development team to maintain security, then we can only rely on community consensus. However, various stories in the past two years have told us that consensus is fragile and disappears quickly.