Topic: Feathercoin Advanced Checkpointing released today - page 4. (Read 11139 times)

No, I am not trolling. All new features are discussed and voted upon in feedback.feathercoin.com. It is the way to do it publicly. Discussing it in the forums is doing it privately. Besides, discussion doesn't mean that people want it. Voting for it in feedback section means that people want it. And how many votes did it get? ZERO. It didn't even get on the feedback ideas list.

I followed the ideas on feedback.feathercoin.com everyday, and there was no mention of any checkpointing, ever. This is completely out-of-the-blue for me (and I was the one who followed feathercoin progress), so what about people who were not following at all?

But I thought this was all done to protect against 51% attack?

It seems you are just trolling. Normally, if I get to learn something (and I learnt a lot from Balthazar's posts in this thread), I would be a bit respectful at the very least.

Thanks again for all the detailed explanations.  

This was one of the later threads https://forum.feathercoin.com/index.php?topic=1878.0

There were threads earlier than this around the time of the first attacks when the suggestions cropped up. The thread titles were differently named so you can do some digging to find out.

Slowpoke? Congratulations.


Again, read closely:


If you see any support or defence here, then you are an idiot.

NVC isn't more scamcoin than FTC or LTC. And you have nothing against this sentence.

There is no contradiction, just read carefully.


Network will be able to function, but becomes vulnerable to 51% attack. .

I just now realized, that the one defending this "feature" is Balthazar - the person who created (?) THE scam coin #1 - NovaCoin.

It is very sad. I honestly expected Feathercoin to become the first currency to integrate Zerocoin, and it would have become the most used currency after BTC and LTC... Instead, the creators chose to "integrate" centralization...

You killed feathercoin today.

You contradict yourself.

They prevents attacker from reorganize attempts, but only while function properly. I.e. 51% still could be executed, but this will require a ddos attack in addition to hashing power.

Yep. Network is able to work without checkpoints (scenarios #1 and #4 in my posts). Unlike trusted blocks, checkpoints are not a part of block chain. Actually, you can patch your client to remove this feature, and it will be compatible with the rest of network.

Then why the f*ck are they needed at all???

This "feature" destroys the most fundamental part of any crypto-currency - decentralization. And now you are telling me, that it is not even necessary?

If that is true, then why it is not even mentioned in feedback.feathercoin.com? Who were these people "asking for it"? Why did they not ask for it publicly, that is in feedback.feathercoin.com ?

You are understanding me right. It's impossible to run more than one such node without a full redesign of concept, because otherwise there will be a constant synchronization conflicts.

But there is a serious difference from RealSolid's trusted nodes approach. Checkpointing node is not a critical part of network. If server would be destroyed by aliens or ddos'ed, this won't event affect the network directly. Network will continue operation without checkpoints.

From feathercoin FAQ ( https://www.feathercoin.com/about/index.php ):

What is Advanced Checkpointing?

Advanced Checkpointing allows us to send out checkpoints without having to redistribute the Feathercoin software. This works by having a 'master node' which checkpoints each block it sees on the network protecting it from the attacker.

1. Who is "US"? What if "US" gets hacked/kidnapped/bribed/blackmailed/killed?
2. What if this "master node" gets hacked/stolen/nuked?

All those are in the works, especially 1 and 5.

There was no shortage of people (including me) asking for ways to prevent the repeated attacks. The advanced checkpointing system was mooted even before the last attack. We were all aware that this was in the works, and as I said there were quite some discussion in the main board (of FTC forum).

I would like to point out that this was not implemented on a whim. There was a lot of discussions on how to prevent the 51% attacks, and this was the most widely accepted short term solution even though most were a bit uneasy about it. Once we find a better solution or FTC becomes big enough this will no longer be needed.

The current model of advance checkpointing is a temporary solution.

But it IS possible now, right? Because there IS only one checkpointing node? Or did I misunderstand you?

And if there are more nodes, what's to stop the attacker from stealing them all?

Consider the example of Liberty Reserve - USA made a strike in 17 countries at once and shut it down. Why? Because there were some central-nodes/points-of-attack available.

"Solving" some security problems by using a centralized solution is not "solving" anything at all - it is returning to the old-fashioned model of PayPal, Liberty Reserve, and many other online financial systems.

Actually I think that BC is nothing more than ugly workaround, sometimes that's required to function properly...

It's planned to drop syncronized checkpoints from NVC since 20 Nov 2013. Currently users are able to switch this option off manually, by using the command line parameters.

This is a misrepresentation of what the feature is for in Bitcoin.  Primarily, it prevents a newly installed node which is being subject to a isolation attack (e.g. by an ISP) from putting it on a fantasy network, it also inhibits a bunch of DOS attacks which could be better solved other ways but were more easily solved with the checkpoints way in the short term. It also triggers some performance optimizations, which, likewise could be done other ways. Bitcoin checkpoints are never placed with a couple thousand blocks of the tip, and thus are not useful against your typical double spend concerns at all.

In more recent times we've been talking about drastically reducing the static checkpoints role in Bitcoin and very likely will in the next major release. We may even remove them completely.

In Bitcoin we would _never_ deploy something that looked liked this advanced checkpointing feature, as doing so would be abandoning our security model. The user community wouldn't accept it, and if by some weird chance they did no sane developer would accept access to the keys lest their lives be put in danger.

Like many other "ways of preventing '51% attacks'" broadcast checkpointing prevents the attack by making the network constantly under the control of a perpetual "ultimate majority" "attacker", though hopefully a benevolent one. ... but thats a return to the old trusted model that runs under classical payment networks like visa... and if you're willing to trust you can construct systems far more efficient than blockchains.

Of course, things are— no doubt— different in the land of crazy altcoins.  Realsolid did a lot worse things in the day with users happily accepting it... so I do not say this to judge— this may be a good, even necessary step considering the environment that you're in... I'd just prefer that you not misrepresent Bitcoin while explaining your feature here.

(As an aside: I was one of the earliest miners on PPC and mined about 250k coins. I stopped when one of the broadcast checkpoints reorged out some of my blocks)