Could SEGWIT bring the mess ?

[Marcel Beliveau]

Hello All,

To my opinion, an innovation like SEGWIT a this step of developpement of Bitcoin is quite dangerous.

1/ Case of a state who wants to bother bitcoin

Do you agree that if i’m ready to invest 10 M$ in mining material + electricity, i can represent a blocking minority for 1 year and prevent from SEGWIT innovation ?

It would not be very expensive for a state to do so.

2/ In case of hard fork

Would it be possible to get an « hard fork » event ? I would like to imagine this scenario.

Old bitcoins (bitcoins which have not been sold for few years) would remain in the initial system (not in the forked one) ? The value of the old bitcoins would fall down quickly.

Thank you for your answers.

Marcel Béliveau

[Foxpup]

Do you agree that if i’m ready to invest 10 M$ in mining material + electricity, i can represent a blocking minority for 1 year and prevent from SEGWIT innovation ?

No. Aside from the fact that it would likely cost a lot more than that, it wouldn't actually prevent anything. All it would do is delay it for a year.

Would it be possible to get an « hard fork » event ? I would like to imagine this scenario.

No. Go ahead and imagine it if you like, but it'll remain imaginary.

[Marcel Beliveau]

Hello,

1/

The total hashrate difficulty is 2*10^9 GH/s.

If i want to represent 10% (so 2*10^8 GHS), i need to buy less than 300 000 "ASIC Buterfly Monarch 700 GH/s".

Considering this ASIC is 200€ expensive, the initial investment would be 60 M€.

After that you have to pay for electricity. But the expenditure is balanced by the incomes of mining.

Anyway, i consider that it's not very expensive for a state to block SEGWIT for this coming year. Either by direct investment or corrupting an existing signficant miner.

It would have an impact on the "crypto world"

2/

I give up for the possibility of an hard fork and will investigate by myself so. But for point 1, i have the feeling i'm right.

Marcel

[achow101]

1/ Case of a state who wants to bother bitcoin

Do you agree that if i’m ready to invest 10 M$ in mining material + electricity, i can represent a blocking minority for 1 year and prevent from SEGWIT innovation ?

It would not be very expensive for a state to do so.

While theoretically possible, there are ways to get around such an attack. If all miners agree that segwit should be deployed, they can configure their software to ignore blocks being produced by the malicious entity thus effectively cutting them out of the blockchain. That malicious miner then runs the risk of mining at an extreme loss as they would be earning no money since their blocks would be constantly be orphaned by the rest of the network. Unless they had an even more significant portion of the hashrate, there is nothing that they can do about it.

[Marcel Beliveau]

If all miners agree that segwit should be deployed,

Code is law (this sentence is hard to understand but will rule the world): 95% of the new blocks must be mined with the new version of the software during 2 weeks

So to my opinion such an agreement can't happen.

they can configure their software to ignore blocks being produced by the malicious entity

If this malicious entity produce blocks which match with the mathematical rules. They will be accepted ?

To refuse these blocks of the "malicious entity", it would require a new BIP (protocol innovation). I don't think it's just a "matter of configuration"

Further in your post, i understand that you are imagining that this malicous entity would be isolated in the blockchain and an hard fork would happen.

To my opinion SEGWIT will not be accepted... And only a crypto currency as close as possible to the philosophy "1 computer = 1 vote" will be able in the future to carry such an evolution at such a stage of development.

It's hard to write it that but i can't think that 95% of the miners will let bitcoin reach the final stage of its development.

Any counter argument is welcome

Excuse my english

[achow101]

If all miners agree that segwit should be deployed,

Code is law (this sentence is hard to understand but will rule the world): 95% of the new blocks must be mined with the new version of the software during 2 weeks

So to my opinion such an agreement can't happen.

Code can be changed. The only code that is law is the consensus code. Stuff that is not consensus such as that agreement can still happen. It's called miner collusion and it is a legitimate thing that can happen.

If this malicious entity produce blocks which match with the mathematical rules. They will be accepted ?

To refuse these blocks of the "malicious entity", it would require a new BIP (protocol innovation). I don't think it's just a "matter of configuration"

Further in your post, i understand that you are imagining that this malicous entity would be isolated in the blockchain and an hard fork would happen.

To my opinion SEGWIT will not be accepted... And only a crypto currency as close as possible the philosophy "1 computer = 1 vote" will be able in the future to carry such an evolution at such a stage of development.

It's hard to write that but i can't think that 95% of the miners will let bitcoin reach the final stage of its development.

Any counter argument is welcome

Excuse my english

You are absolutely incorrect.

It does not require a new BIP. It does not require a protocol change. It does not cause any sort of consensus change. It is literally just miners choosing what blocks they want to build upon. This can be done with a slight modification to the software to reject to build on top of blocks of a certain type (i.e. ones that do not signal segwit). There will be no fork so long as the miners still follow the consensus rules, i.e they follow the longest chain. The malicious miner's blocks would still be valid, just that some miners would refuse to build their next block on top of one mined by that miner.

[Marcel Beliveau]

So I'm imagining that a malicious entity (which represents let's say 10% of the total mining power) would refuse to implement the new SEGWIT change and would continue to mine blocks in the old way.

If it would happen other miners can get along to never continue the blockchain from a block which has been done from this malicious miner. A "miner collusion" as said achow101.

But if a miner (from the "miner collusion") who just wants to make money (with short term perspectives), can accept to build from the malicous blocks to be the first do discover the next block ?
This minor would be a "dissident" and would get bitcoins because he discovered a new block faster than other fair miners.

One fair miner (from the "miner collusion") could think "we did an alliance for the future of bitcoin...but some of us are cheating...I so also will accept all blocks and let's forget about SEGWIT... I want money now"

This "minor collusion" seems a bit fragile, no ?

Marcel

[cr1776]

...let's say 10% of the total mining power...

Are you asking about a hypothetical that might represent the actual threat from ViaBTC (or some other pool - it doesn't really matter)? 

If so, one would think that the malicious pool would lose members of the pool if they were blocking segwit while waiting for a different block size increase.  This blocks some of the other segwit advantages.  I doubt that every member of the malicious pool would support halting progress as an attempt to force a different path when segwit is compatible with larger block sizes too. 

Anyway, I think we'll know the answer to the question as to whether the threshold will be reached soon enough.

[Marcel Beliveau]

This pool would loose members for sure. And this pool would die.

I'm really thinking about a state or group of banks who wants to attack bitcoin. And who would be ready to invest money (100M€ is nothing for them and it allows them to represent a blocking minority) to prevent from SEGWIT adoption....because it would be a good way to start fighting bitcoin.

Up to now, the only counter argument i read is : would be a "miner collusion"....

If miners never get along (i fear they prefer money than ideology  )...SEGWIT would not become the new standard. And I try imagine the consequences....

[amaclin]

Do you agree that if i’m ready to invest 10 M$ in mining material + electricity

There is much more cheap way.
You have not to buy any hardware.
Just create a pool and pay 105% to your miners. Or even promize to pay.
In a couple of monthes you would have 51% hashrate for anything you want in bitcoin network  

[Marcel Beliveau]

Good idea amaclin 

Anyway, i'm looking forward to seeing if this BIP will overcome the difficulties.

Where can i see a charts with all miners and the version of the program they use ?

Marcel Beliveau

[Marcel Beliveau]

I spent my day investigating on it.

You can track evolution here (adoption of SEGWIT):
https://coin.dance/blocks

I'll stay ready to switch to XMR if needed.

Marcel is a newbie