i guess sooner or later some people were bound to show up when proof of stake is mentioned and of course the coin they want to discuss is nxt, not anything else.  Look if you like nxt good for you. If you want the documentation I based my comments on use google and look up what people say about it. Also keep in mind the 'source' code was not initially available https://bitcointalk.org/index.php?topic=394916.0

If you disagree with my opinion or the opinion of the Ethereum dev. about proof of stake and the concepts he cited be my guest.

One fact about this altcoin forum around here in general I have noticed

Certain coins seem to have some type of 'protected' watchers that are watching all unmoderated threads.   I won't name coin names.  There are several.

Most coins if you post a negative comment on their thread it will be ignored or others may join in. Rare will someone defend the coin in fact the most you may see if someone , maybe on the development team tell you if you don't like the coin don't mine it and gtfo. 

Now ---- certain coins --a select few -- things seem to happen differently.

If a negative comment without much merit is posted like 'this coin sucks' , it won't take long for others to say they like it and just post other items..... this 'forum bumping' technique is a very old tactic and even employed by the United States and likely other governments to sway public opinion on certain things normally related to politics.  This is not a conspiracy theory there are published foia documents that confirm it.

If a negative comment is posted to a coins thread that actually has some foundation and or documentation to it as to what flaw exists or why they will not support it.... a different approach is used.   Multiple accounts slam that user, often following other posts they made elsewhere here in this forum and negate them even to the point of stating things like 'you post negative comments about several coins' .... ect....   Some people have even been confronted online or in person and threatened.
I know of a few confirmed incidents like this.


If a coin thread has a multitude of people responding or even paying attention to every negative or questionable item posted about that coin proceed with caution.  Honest , fair, legit and real open source projects have nothing to hide and no place to hide it. Their code is released to the world and can be tested by anyone. 

Personally I think if you are using any cryptocurrency at all and it is not 100% open source from day one you should seriously reconsider your position but in the end it is up to you.

Coins you think are run by party x could actually be under control of someone else, like a government agency, organized crime ring or many many other things/people ..... use your imagination. 

In closing I will say I stand behind all prior posts I made here.

If you have FACTS that refute anything I stated post them to the thread.

I don't care if anyone likes my opinions or agrees with them or feels differently.

Also, you may want to think twice about attempts to bother me personally as it has happened in the past when I have criticized things. I don't care how many fake sock puppet accounts come of of the sky. I am not afraid of you, whatever government agency you work or are in informant for or what other organizations you are associated with. I can say this with confidence since I am not a criminal.

To summarize the discussion, known claimed attacks on proof-of-stake distributed consensus algorithm(and concrete implementations) at the moment:

1. Short-range attack  - attacker can offer better chain started few blocks behind current canonical chain. The attack is possible at the moment, the only likely outcome though is just gathered fees increase for an attacker. In our simulations this kind of attack is possible mostly when a long delay occurs due to low target. By the way, the attack has positive aspect for network, as it shorten delays average between blocks. So attacker gets extra fees for a good job done 

2. Long-range attack - attacker can start fork hundreds or thousands blocks behind current chain. From our investigations the attack isn't possible. 

3. Nothing-at-stake attack - not possible at the moment! Will be possible when a lot of forgers will use multiple-branch forging  to increase profits. Then attacker can contribute to all the chains(some of them e.g. containing a transaction) then start to contribute to one chain only behind the best(containing no transaction) making it winner.  Previous statements on N@S attack made with assumption it costs nothing to contribute to an each fork possible and that makes N@S attack a disaster. In fact, it's not possible at all to contribute to each fork possible, as number of forks growing exponentially with time. So the only strategy for a multibranch forger is to contribute to N best forks. In such scenario attack is possible only within short-range e.g. with 25 confirmations needed 10% attacker can't make an attack. And attack is pretty random in nature, it's impossible to predict whether 2 forks will be within N best forks(from exponentially growing set) for k confirmations. So from our point of view the importance of the attack is pretty overblown.

4. History attack - attacker can buy whale's private key for $5 and build alternative story. Solved with some checkpoints now, located behind max rollback possible, so the solution is not so scary in terms of centralization etc.


If you know any other kind of attack, please add. Please note IPO properties of a concrete coins etc isn't related to proof-of-stake distributed consensus problems.

And Consensus Research is going to work on better proof-of-stake prototyping & implementation !

If someone tries to push me around I will look through your coin /code/ everything else and I am very skilled at finding out vulnerabilities and information.  If provoked I will publish my work. That aside, when left alone I tend to allow a 'confrontation' with another to be a one time thing and not go looking to screw with other people.