Thanks.

Do I need to do anything special to run a public node? Which port should I open? Does Qora use hallmarks? How can I check that others can see my node?

How do I find what version I have? I can't see it in the UI or in the folder. There doesn't seem to be a readme.txt with the version or anything, or an About box.

The Marketplace is the main thing you missed. Nxt has been in the doldrums recently, featurewise, because the implementation switched from storing everything in memory to storing it all on disk with a database, and that was such a big change everything else had to wait. That version (1.3.1) is now live, and we can expect a backlog of other features to come rapidly over the next few months.

I'm guessing you mean Nxt, and I don't think it works like that. Both being written in the same language doesn't make it trivial to port features from one currency to another. Qora and Nxt are completely different source. Ideas might be reused, but that'll happen regardless. The reality is that Nxt has a long roadmap with lots of features planned, and the devs have too much on their plate already to spend time porting code from Qora. So I wouldn't worry about it, any more than Nxt worries about Qora taking the Marketplace.

The lowering of the hashrate is the problem. The lower the hashrate, the cheaper it is to attack Bitcoin.

The cost of attacking a coin generally depends on its market cap. For example, the more BTC is worth the more the block reward and transaction fees are worth, the more hash-power the network gets and the more expensive it becomes to acquire 51%. Similarly with PoS coins, the higher the market cap the more expensive buying 51% of stake is. So, if you want to build a feature on top of a block-chain, and you care about security, pick the one with the highest market cap. Last time I checked, Nxt's market cap was 60 times XCR's.

(I'm not getting at XCR especially. This argument gets used against Nxt, too. Some say everything should be built on top of Bitcoin because its market cap is so high.)

Not really. Selling locks in your losses. By the time the price gets so low that I truly write Bitcoin off, I'll already have lost so much that losing the residual value won't make much difference. I'd rather hold and hope something changes. A trader would sell on the way down, then buy it all back at the bottom, but to do that you need to watch the market like a hawk, guess correctly where the bottom is, and have nerves of steel. I'm not that guy.

The thing is, "price" is the wrong question. It'd be existential threats to Bitcoin that would make me sell. Like flaws in the maths, new legislation or competition from a new coin. Now, I am a fan of certain PoS coins, and if it looked to me as though one of those coins was kicking Bitcoins arse in the markets, then I'd sell my BTC because it would be over. That's not what's happening today. The fiat isn't flowing out of Bitcoin and into some other crypto-currency. It's crypto-currencies as a whole that are crashing. And I don't see a reason for that. The value proposition is still sound. At some point you have to have some faith in your own judgement and just hold on.

Nxt doesn't use checkpoints. Please don't talk about PoS coins as if they were all the same. They use different algorithms.

That used to be true, but isn't any more. Nowadays the transaction that sends NXT to a new account also attaches a 256-bit public key. If someone else got there first, the transaction fails and the funds aren't lost. If the transaction succeeds, then you need to break the 256-bit cryptography to steal the funds.

Whether this core change was necessary is a moot point. I don't think it was a real-world danger. Breaking 64 bits is possible, but hard, and I don't believe there's any evidence anyone has actually done it to hack a Nxt account. It's certainly not what happened to the original poster. Check the transactions, eg here. You'll notice there were outgoing transactions before the funds got taken. So this theft was not due to the issue you describe. It was due to the password being compromised, almost certainly because it was too weak.

Sure. But Gandi did not want answers based on trust in personalities, so I tried to point to some objective facts.

Mind you, it's hard to say whether a coin is a "scam coin" because that phrase gets bandied about so much it has lost its meaning. Certainly an Open Source coin could still be scam. And certainly Qora has put in many months of creative coding effort, which the true scam coins don't bother with.

He doesn't have to be come an amateur cryptologist - quite the reverse. We discourage that. What he needed to do was use the password the default client provided. That would have been 12 words, with over 128 bits of entropy. It's because he chose to use his own password that he needs to know how to make a strong one. His refusal to say what his password actually was makes it impossible to say whether he did that. He is refusing because he's used similar passwords, with many of the same words, elsewhere. That too is a weakness. We discourage amateur cryptology because they so often get it wrong.

You don't. Just use the password the default client generates for you.

The problem isn't fundamental; it'd be easy to fix in the client. I'd rather it used a wallet.dat, same as Bitcoin. Some Nxt clients do. The downside is that if you lose the wallet.dat file, you lose access to your coins; and that has happened to people. Swings and roundabouts. It would help if the client didn't allow users to pick their own passwords at all. (I also think the client should ask for the account code, and only ask for the password when they actually make a transaction.)

Qora has had voting for a while; Nxt still doesn't have voting in its core. Nxt has had an Asset Exchange for a while, Qora only just got its AE, and it has significantly different features (eg trading asset for asset rather than asset for coin). Nxt and Qora are now different enough that we shouldn't worry if some of the code used to be the same.

It's an interesting discussion point. The argument for PoS put here is not a passing meme, or even a feature, so much as a fundamental efficiency. I expect to see fees in PoS currencies ending up much lower than PoW ones, and then, if other factors are equal (obviously people disagree about that), then people will shift to the cheaper system if they can. I expect payment processors will make it easy for merchants to accept payment in a variety of crypto-currencies. It's software - they can write it once, roll it out to thousands of merchants, and there-by get a competitive advantage over other payment processors that support fewer coins. There's no loyalty. The best coin will get the bulk of the business, and lesser coins will fade gradually into irrelevance until they are not worth having as an entry in a combobox. Certainly industries do switch technologies when it makes sense to.

I don't believe that will ever happen, in the sense that the original block-chain and protocol will continue indefinitely. Bitcoin won't evolve; it'll be replaced and the original will fade away. That's because there will never be 100% consensus to upgrade it, and no-one can force the holdouts to shift. It's easier not to try.

Whether the replacement will be some new thing devised by the Bitcoin community itself, or an outside coin (perhaps one that already exists) is another matter.

I just don't see that. If one coin is demonstrably better (eg by having lower transaction fees and no downside), why wouldn't people switch to it? They switched from Alta Vista to Google. They switched from Myspace to Facebook. They switched from leaded to unleaded petrol, and many switched again to diesel. It's one thing to claim a given coin isn't significantly better, and another to claim the best coin won't win.

Nxt disallows block-chain re-organisations past 720 blocks, so you have to mount your attack within 12 hours of selling your coins. Selling 51% of NXT, or even 20% of NXT, within a 12-hour window would crash the price. You'd lose a fortune. This is not a cheap attack.

Nothing I wrote was false. Nxt is secure; no-one has successfully attacked it (as opposed to attacking exchanges or individuals). If you read the quote you linked to, here, Gregory Maxwell was very clearly being specific to Peercoin and Peercoin's flaws. He may have written other things elsewhere; I just commented on the bit you linked.

A hack of an exchange is not a 51% attack. 5% is not enough coin to mount an attack. The hack had no effect on block-chain security; the hacker couldn't do anything that Bter couldn't have done.

If you try to buy so many, the price will rise. If you succeed, you will find you are attacking yourself.

You have to have owned them within the last 12 hours or so, because although Nxt doesn't have checkpoints, it does disallow block-chain reorganisations past 720 blocks. This means to do what you suggest you have to acquire 51% of Nxt and then sell them all off within 12 hours. Dumping in such volume would crash the price, and you'd lose a lot of money.

The mining gear can be used for other PoW coins that use the same ASICs.

He's talking about Peercoin. It's a different algorithm. His comments don't apply to Nxt.

Nxt doesn't use checkpoints. Although it adds features fairly often, its core model doesn't change often and new features don't make it harder to attack. Even if they did, I don't see how that would affect mounting a 51% attack. Getting to control 51% of Nxt would be implausibly difficult because of the difficulty in acquiring that many coins.

It's bad reporting. The bank actually says:

"Digital currencies do not currently pose a material risk to monetary or financial stability in the United Kingdom. Should they achieve limited adoption as a payment system, they are unlikely to undermine the Bank’s ability to achieve monetary stability. While that could, in theory, change if sterling were abandoned in favour of an alternative currency for a significant fraction of the economy, such a scenario is considered extremely unlikely at present. A variety of potential risks to financial stability could emerge if a digital currency attained systemic status as a payment system, most of which could be addressed through regulatory supervision of relevant parties."

That's the conclusion. The media are distorting it.

Wrong question. I think you really want to know how to make it safer to accept zero confirmations. Having nodes relay (as flagged) double-spend attempts would be one way.

In Nxt, anyone can forge (possibly through leasing). It's not something reserved to the rich and powerful. The percentage returns are the same.

In Nxt, forging is something done to help secure the network. It's not done to make money. The income from forging is currently around 0.2%/year, which is trivial. It's expected to become lower once we reduce the fees. Validating transactions is so cheap in PoS,  it leads to a different mentality to PoW, because there aren't millions of dollars involved every day. (That's part of why "nothing at stake" doesn't apply. The increased income you'd get from forging on multiple forks isn't worth the loss of security. NaS is a criticism only someone from the PoW world would make.)

Only if they choose to reveal their power, and only if they aren't suddenly hijacked by another party.

No. For example, I have two Nxt accounts. One I use for forging; it has a zero balance so it doesn't need to be secure. The other stores the coins and leases to the forging account; it doesn't need to be public.

PS I try to restrict my comments to Nxt because that's the PoS I know best. Other PoS may have other solutions and/or problems.

So 36 million isn't enough to motivate hackers? Of course it is. Nxt is under continual attack, eg from hackers scanning for weak passwords. If the core system was weak, it'd be broken.

The first of those was about an exchange getting hacked, not the currency itself. The second was about a transaction getting accepted and then orphaned, which is something that can happen in any distributed crypto-currency and again does not mean the currency's security is weak. It's happened in Bitcoin, for example. Neither have anything to do with "nothing at stake".

Bugs can arise in any software. There's no reason to think they will take longer to fix in PoS than in PoS. If anything, it's the opposite. Bitcoin has shown itself notoriously slow to fix flaws. Transaction mutability is still not fixed, for example.