6 ms·

tl:dr NSA invented Bitcoin?

by dcc1 13y ago

arh68 13y ago
It doesn't solve the decentralization problem. > Without a trusted certification authority and a secure infrastructure, the above four security features cannot be achieved, and electronic commerce becomes impossible over an untrusted transmission medium.
- dcc1 13y ago
  You right, no proof of work either
ferdo 13y ago
Not necessarily, but they were out in front of the idea in the 90's.
Scaevolus 13y ago
Their proposal requires a central bank. They discuss how to do "offline" transactions without contacting this central authority, but double-spending would only be detected when money is "deposited" back into the central bank.
- betterunix 13y ago
  It is worth pointing out that the double spending is not merely detected in these systems; the bank is able to compute a proof, that anyone can verify, of a particular party's guilt. This allows the bank to create a blacklist, or to use a legal system, etc.
- nly 13y ago
  It doesn't necessarily require a central bank, which everyone must be compelled to use, it just requires a banking system. If someone wishes to pay you, and happens to use a different bank to yourself, then your bank (whom you, admittedly, have to trust) can work on your behalf, directly with the sourcing bank, to claim the funds. There's quite good reason to trust in this system because our bank knows that the sourcing bank can identify double-spenders. The plus side of such a system is honest bank customers still get complete anonymity, even if the banks conspire against you. The downside is you can never know if your bank is conspiring against their customers as a whole i.e. by not operating in line with their inflation/reserve policy... which of course is one of Bitcoins best features.
betterunix 13y ago
1. They are describing the invention of David Chaum 2. What they are describing has a security definition and can be proved secure. Bitcoin has no security definition, no proof of security, and is vulnerable to polynomial time attacks.
- maaku 13y ago
  > Bitcoin has no security definition, no proof of security, and is vulnerable to polynomial time attacks. Cite?
  - betterunix 13y ago
    It is pretty hard to cite the lack of a security definition and the lack of a security proof. As for the polynomial time attack, it is describe in the original Bitcoin paper, at the end of Section 4: http://bitcoin.org/bitcoin.pdf http://bitcoin.org/bitcoin.pdf It is also described here: https://en.bitcoin.it/wiki/Weaknesses#Attacker_has_a_lot_of_computing_power https://en.bitcoin.it/wiki/Weaknesses#Attacker_has_a_lot_of_... And in this criticism by Ben Laurie: http://www.links.org/files/decentralised-currencies.pdf http://www.links.org/files/decentralised-currencies.pdf
    - maaku 13y ago
      Ok, that's not an attack against the cryptography of the system, which you're original post implied. E.g, you can't use a polynomial-time algorithm to spend coins which belong to me.
      - betterunix 13y ago
        "that's not an attack against the cryptography of the system" I am not sure what you mean. What do you think this is an attack against? "you can't use a polynomial-time algorithm to spend coins which belong to me." In some situations I can. If, for example, you received your money from me, I can take the money from you and transfer it to someone else. The attacker can also stop you from completing transactions and stop you from receiving rewards for mining.
gwern 13y ago
No; Bitcoin sacrifices some of the nice features of the known possible digital cash systems in 1996 in exchange for an ad hoc sort of decentralization. Arguably, that's why it's succeeding - decentralization turned out to be more important than either high-powered security proofs or efficiency (my essay on the topic: http://www.gwern.net/Bitcoin%20is%20Worse%20is%20Better http://www.gwern.net/Bitcoin%20is%20Worse%20is%20Better ).
- ferdo 13y ago
  Tatsuaki Okamoto has quite the crypto and coding chops: https://www.google.com/#sclient=psy-ab&q="Tatsuaki+Okamoto"+c%2B%2B+Visual https://www.google.com/#sclient=psy-ab&q="Tatsuaki+Okamoto"+... http://academic.research.microsoft.com/Author/1002804/tatsuaki-okamoto http://academic.research.microsoft.com/Author/1002804/tatsua... http://www.informatik.uni-trier.de/%7Eley/pers/hd/o/Okamoto:Tatsuaki.html http://www.informatik.uni-trier.de/%7Eley/pers/hd/o/Okamoto:...
vy8vWJlco 13y ago
With their records, if they didn't make it, they should at least know who did (who posted the paper, who was mining during the early days, etc...).

tl:dr NSA invented Bitcoin?

by dcc1 13y ago

tl:dr NSA invented Bitcoin?

arh68 13y ago

It doesn't solve the decentralization problem. > Without a trusted certification authority and a secure infrastructure, the above four security features cannot be achieved, and electronic commerce becomes impossible over an untrusted transmission medium.

dcc1 13y ago
You right, no proof of work either

ferdo 13y ago

Not necessarily, but they were out in front of the idea in the 90's.

Scaevolus 13y ago

Their proposal requires a central bank. They discuss how to do "offline" transactions without contacting this central authority, but double-spending would only be detected when money is "deposited" back into the central bank.

betterunix 13y ago
It is worth pointing out that the double spending is not merely detected in these systems; the bank is able to compute a proof, that anyone can verify, of a particular party's guilt. This allows the bank to create a blacklist, or to use a legal system, etc.
nly 13y ago
It doesn't necessarily require a central bank, which everyone must be compelled to use, it just requires a banking system. If someone wishes to pay you, and happens to use a different bank to yourself, then your bank (whom you, admittedly, have to trust) can work on your behalf, directly with the sourcing bank, to claim the funds. There's quite good reason to trust in this system because our bank knows that the sourcing bank can identify double-spenders. The plus side of such a system is honest bank customers still get complete anonymity, even if the banks conspire against you. The downside is you can never know if your bank is conspiring against their customers as a whole i.e. by not operating in line with their inflation/reserve policy... which of course is one of Bitcoins best features.

betterunix 13y ago

1. They are describing the invention of David Chaum 2. What they are describing has a security definition and can be proved secure. Bitcoin has no security definition, no proof of security, and is vulnerable to polynomial time attacks.

maaku 13y ago
> Bitcoin has no security definition, no proof of security, and is vulnerable to polynomial time attacks. Cite?
- betterunix 13y ago
  It is pretty hard to cite the lack of a security definition and the lack of a security proof. As for the polynomial time attack, it is describe in the original Bitcoin paper, at the end of Section 4: http://bitcoin.org/bitcoin.pdf http://bitcoin.org/bitcoin.pdf It is also described here: https://en.bitcoin.it/wiki/Weaknesses#Attacker_has_a_lot_of_computing_power https://en.bitcoin.it/wiki/Weaknesses#Attacker_has_a_lot_of_... And in this criticism by Ben Laurie: http://www.links.org/files/decentralised-currencies.pdf http://www.links.org/files/decentralised-currencies.pdf
  - maaku 13y ago
    Ok, that's not an attack against the cryptography of the system, which you're original post implied. E.g, you can't use a polynomial-time algorithm to spend coins which belong to me.
    - betterunix 13y ago
      "that's not an attack against the cryptography of the system" I am not sure what you mean. What do you think this is an attack against? "you can't use a polynomial-time algorithm to spend coins which belong to me." In some situations I can. If, for example, you received your money from me, I can take the money from you and transfer it to someone else. The attacker can also stop you from completing transactions and stop you from receiving rewards for mining.

gwern 13y ago

No; Bitcoin sacrifices some of the nice features of the known possible digital cash systems in 1996 in exchange for an ad hoc sort of decentralization. Arguably, that's why it's succeeding - decentralization turned out to be more important than either high-powered security proofs or efficiency (my essay on the topic: http://www.gwern.net/Bitcoin%20is%20Worse%20is%20Better http://www.gwern.net/Bitcoin%20is%20Worse%20is%20Better ).

ferdo 13y ago
Tatsuaki Okamoto has quite the crypto and coding chops: https://www.google.com/#sclient=psy-ab&q="Tatsuaki+Okamoto"+c%2B%2B+Visual https://www.google.com/#sclient=psy-ab&q="Tatsuaki+Okamoto"+... http://academic.research.microsoft.com/Author/1002804/tatsuaki-okamoto http://academic.research.microsoft.com/Author/1002804/tatsua... http://www.informatik.uni-trier.de/%7Eley/pers/hd/o/Okamoto:Tatsuaki.html http://www.informatik.uni-trier.de/%7Eley/pers/hd/o/Okamoto:...

vy8vWJlco 13y ago

With their records, if they didn't make it, they should at least know who did (who posted the paper, who was mining during the early days, etc...).