Yes I was wrong about checkpoints being “not enforced” the reason I was wrong is because thats what it says on peercoin.net under “Frequently asked questions” myth 2
“Checkpoints are like an alert message, clients listen to them but does not enforce the checkpoint by default. Users have the choice to enable the enforcement of checkpoint, but it’s a conscious choice users must take. This means the developer responsible for the checkpoint must gain community consensus before using them, developer cannot arbitrarily force a block chain reorganization onto the users. Generally speaking the checkpoint feature should not be used without 51% attack emergency. The risk of 51% denial-of-service attack on block chain is real, especially to a smaller network. In fact I wouldn’t exclude such a possibility to even bitcoin. Of course such an attack on bitcoin would likely not come from an individual due to the resource required. But it’s irresponsible to say that’s not possible. Just imagine what would happen if bitcoin stops processing transactions for a few days. The advanced checkpoint feature in xpm is specifically designed to deal with this situation. Yes the network would turn into quasi centralized mode by community consensus, however that’s obviously a lot better than admitting defeat and giving up.”
Sunny King
This is false or misleading information.[/quote]
The probable answer: Sunny King referred to Primecoin when he wrote this, not to Peercoin. In Primecoin, checkpoints must be enforced by the users.
This part of the website should be changed.[/quote]
I checked peercoinmyths.com and the whole quote is listed on there. Sunny begins the quote by talking about XPM. He even mentioned XPM again later in the quote. Nowhere in the quote did he say anything about Peercoin…
“XPM is already decentralized. The checkpoints in xpm is like the alert message, clients listen to them but does not enforce the checkpoint by default…”
So we have information about Primecoin on peercoinmyths.com and peercoin.net. People have been using this quote all over the place to explain Peercoin checkpoints to people. We need to be more careful. Can we get this fixed and put the right information up? Do we have the right information available?
I think also this should be fixed fast. I have posted a suggestion for a text which conserves the neutral part of Sunny King’s cite. But I want someone to look for errors as I am not a native English speaker:
Checkpoints are an additional security measure and were introduced to protect the Peercoin network from attacks when it was in its infancy. Sunny King explains:
“The risk of 51% denial-of-service attack on block chain is real, especially to a smaller network. In fact I wouldn’t exclude such a possibility to even bitcoin. Of course such an attack on bitcoin would likely not come from an individual due to the resource required. But it’s irresponsible to say that’s not possible. Just imagine what would happen if bitcoin stops processing transactions for a few days.”
As Peercoin’s network has grown substantially in the past year, checkpoints will be phased out in one of the next versions, probably in PPC 0.5.
I don’t think that Sunny King quote is good enough to properly explain things. It basically says that an attack is possible, but it doesn’t address the myth. We need to know why Peercoin isn’t centralized because of checkpoints. Is there anyone here that can properly explain this in simple terms? We don’t have to have a Sunny King quote. We just need a good explanation that is correct.
Peercoin’s checkpoints aren’t all that different from the “hard” checkpoints in Bitcoin, Litecoin, etc. The difference is that Sunny King or whoever has the private key can add new checkpoints dynamically (by signing blocks in the blockchain). With Bitcoin, et al adding additional checkpoints requires making changes to the source code and releasing a new version of the client. I don’t see how what Peercoin is doing is any more centralized than what Bitcoin does.
Yes, for me it has a “centralized element”, as I understand the checkpoint question. It is not completely centralized, but there are nodes with more control (those having the checkpoint private key, for now - it seems - only Sunny King) than the others.
Perhaps, the explanation can go from “Myths” to the “FAQ”? So we can address the whole question. I also have no problems with removing the Sunny King quote. My pull request was meant as a “quick fix” so we aren’t longer spreading the false information about XPM.
A new suggestion: Move the part about checkpoints from “Myths” to the FAQ. The Myth can be replaced by one of the other two popular myths: “Peercoin was insta-mined” or, even better, “Myth 9 - Peercoin (PPC) unfairly rewards the large coin holders.”
The suggested new text, without Sunny’s quote:
I have heard that Peercoin uses centralized checkpointing.
The checkpoints system is an additional security mechanism introduced in the first version of Peercoin. Its goal was to protect the young Peercoin network against some attack scenarios. Checkpoints work like an alert system and allow developers to force other nodes to use their version of the blockchain if there is danger of an attack.
As the Peercoin network is growing fast, this mechanism is probably not longer necessary. According to the lead developer Sunny King, in the next versions of the Peercoin client it will be converted into a voluntary system (like already in Primecoin) and then removed completely.
If you think it’s OK, I will integrate it into the peercoin.net text with another pull request to the website. (As I have received a very generous tip for my little change, let me do this one for free )
Fine with changing the Myths regarding the centralised checkpointing.
Have a bit of an issue with Myth 9 - Peercoin unfairly rewards the large coin holders. My understanding is that it is still quiet a challenge (low chance) for small coin holders to successfully mint a block. However if they do mint a block they are awarded equally. Until the chances of minting a block with say 50 PPC and 90d coinage are clear, I would refrain from having that on the website as a debunked myth
I actually asked JBT to see if he could get Sunny to give us a Peercoin specific quote on checkpoints. That would clear up any confusion and give us something to put up.
[quote=“Cybnate, post:8, topic:1398”]Fine with changing the Myths regarding the centralised checkpointing.
Have a bit of an issue with Myth 9 - Peercoin unfairly rewards the large coin holders. My understanding is that it is still quiet a challenge (low chance) for small coin holders to successfully mint a block. However if they do mint a block they are awarded equally. Until the chances of minting a block with say 50 PPC and 90d coinage are clear, I would refrain from having that on the website as a debunked myth[/quote]
Right. Small coin holders get less chance to win the POS block lottery.
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