Namecoin is Prime for a 51% attack

doublec
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Re: Namecoin is Prime for a 51% attack

Post by doublec »

vinced wrote:I released version nc0.3.24.62 with a corrected lockin patch from makomk. Please test.
The patch doesn't change the LockinHeight function. Does that matter?

vinced
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Re: Namecoin is Prime for a 51% attack

Post by vinced »

doublec wrote:
vinced wrote:I released version nc0.3.24.62 with a corrected lockin patch from makomk. Please test.
The patch doesn't change the LockinHeight function. Does that matter?
Sorry. Try now.
!v | Namecoin founder | https://dot-bit.org/

doublec
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Re: Namecoin is Prime for a 51% attack

Post by doublec »

vinced wrote: Sorry. Try now.
Thanks, testing now. I think a fix for ArtForz's Geitz Geld attack would be useful before merged mining is activated. Without this a >51% attacker can keep difficulty low while generating blocks fast. With merged mining this means they can attack the namecoin network 'for free' since they are earning bitcoins while doing it. The attack is described here: https://bitcointalk.org/index.php?topic=43692.0

Davincij15
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Re: Namecoin is Prime for a 51% attack

Post by Davincij15 »

vinced wrote:I released version nc0.3.24.62 with a corrected lockin patch from makomk. Please test.

For now, I suggest we lock in often while we investigate a more permanent solution to the timing attack.

We definitely need more hash power too and that should come with merged mining. If an attack starts, we could restart the chain at the last lockin with merged mining.
Thanks this is the first message I have read from you or Kahl once the attack was announced it seemed you guys had given up without a fight. You need to communicate with the community a bit more than you currently do.

Next time there is a crisis you should at least say you are working on solutions to the problem.

BTW I will upgrade tomorrow any docs on how to lockin.

doublec
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Re: Namecoin is Prime for a 51% attack

Post by doublec »

vinced wrote: Sorry. Try now.
I can confirm the latest master with the checkpoints works fine. I downloaded a clean block chain with it. I also tested that it correctly rejected bad blocks at those heights.

Davincij15
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Re: Namecoin is Prime for a 51% attack

Post by Davincij15 »

doublec wrote:
vinced wrote: Sorry. Try now.
I can confirm the latest master with the checkpoints works fine. I downloaded a clean block chain with it. I also tested that it correctly rejected bad blocks at those heights.
If there is anything I can do let me know. I'm a resource please let be of assistance.

doublec
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Re: Namecoin is Prime for a 51% attack

Post by doublec »

Davincij15 wrote: BTW I will upgrade tomorrow any docs on how to lockin.
You just need to update to the latest git to get the lockin to block 18940. Lockins can be added by looking at namecoin.cpp, in the LockinHeight and Lockin methods. You add the height of the new locking, and the hash for the block at that height.

BitcoinEXpress
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Re: Namecoin is Prime for a 51% attack

Post by BitcoinEXpress »

The timing attack has been tested against a merged mining NMC/BTC testnet, as ArtForz has said for months the merged mining negates the lock in points. You're burning time on lock in points. You will also need to get the majority of miners to do this quickly with updated clients. Right now if I wanted to I could kick in 68 gh/s by myself and literally stop your lock in dead in the tracks. But I said I wouldn't make a move till 19101 and that's the way it will be. ;)

If you read ArtForz responses to the original thread I made at Bitcoin talk he talks about a specific flaw to NMC.

Solidcoin update:
As most are aware CH is special. He publicly challenged me, even taunted me to some degree that Solidcoin was bullet proof. He asked for a demo on his bullet proof testnet featuring his unreleased "hardened version 1.10". In less than 30 minutes it was ripped to shred with a new fork almost 5 times the size of the original. One hour later, CH announces Solidcoin will shut down pending a fix.

I am the last to give CH any props but Soildcoin is factorially more hardened than NMC. If you guys were strategic, you would do like CH and try to shut down NMC considering your exchanges are non functional and you do not use time as a retarget factor. If you pump in more hash rate and get to 19100, you will never make it to 19200. By 19150 we will control the chain due to more than a confirmed 250 gh/s and possible three times that amount coming on line at block 19101.

decisions, decisions,

@Davinci
Make another smart ass comment directed at me in any forum and I might decide to say to hell with 19100. You talk about "spending smart" I suggest you do the same with your words. I have never attacked anyone personally other than CH. At this point an negotiated settlement is possible and no it doesn't involve NMC, BTC or the transfer of any alt coin.

Davincij15
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Re: Namecoin is Prime for a 51% attack

Post by Davincij15 »

BitcoinEXpress wrote: @Davinci
Make another smart ass comment directed at me in any forum and I might decide to say to hell with 19100. You talk about "spending smart" I suggest you do the same with your words. I have never attacked anyone personally other than CH. At this point an negotiated settlement is possible and no it doesn't involve NMC, BTC or the transfer of any alt coin.
Just do your dirt now, don't threaten me. I am here to support, build and create. There is a software flaw. like all software has, you proved it, we believe you, so why destroy this software and it's community?

Any banker can destroy, but real work and effort improves society and make life better for everyone. You could say "that what does not kill us makes us stronger", but you are not and unexpected disaster you can choose to do this damage or not.

So please do it now if you want to do it at all.

With no respect, and no kind regards,
Davinci

doublec
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Re: Namecoin is Prime for a 51% attack

Post by doublec »

BitcoinEXpress wrote:Right now if I wanted to I could kick in 68 gh/s by myself and literally stop your lock in dead in the tracks. But I said I wouldn't make a move till 19101 and that's the way it will be. ;)
Not really, you'd overrun the people who are not using a locked in client. Those that are locked in will continue as normal. Your mined coins will be useless as they can't be used anywhere.

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