4 ms·

This is insane. Apparently Titan can do 10-20 petaflops per second. I didn't think before, but they may be decoding AES-128.

betterunix 13y ago
I doubt that they are decoding AES, except perhaps for the highest-value targets. I would guess that that computing power is a shared resource, not something that can be dedicated to a single task like that. They are probably using it for numerous data mining applications, probably a lot of traffic analysis, some signal processing, etc. Even if the NSA has the resources needed to crack AES128, those resources would almost certainly be better used on other tasks.
- marshray 13y ago
  I agree. There is no known attack on AES-128 which comes anywhere close to the capability of any known supercomputer within any reasonable time period. Except maaaybe the aggregate computing power of the entire PlayStation Network for a long long time. I haven't run the numbers for AES. EDIT: Yeah, no way without an algorithmic breakthrough.
  - jacquesm 13y ago
    There is no publicly known attack, it is possible that there are undisclosed vulnerabilities in AES-128 that the NSA is aware of today. Is there any precedent for a weakness like that where an agency like the NSA was already aware of a weakness before it became public?
    - marshray 13y ago
      A couple of cases come to mind where the NSA is seemed to demonstrate superior awareness of cryptanalytic attacks. But note that in neither case did the NSA recommend the use of a cipher that was weaker than the number of bits on the label. 1. Differential Cryptanalysis https://en.wikipedia.org/wiki/Data_Encryption_Standard#NSA.27s_involvement_in_the_design https://en.wikipedia.org/wiki/Data_Encryption_Standard#NSA.2... A general technique, but the DES standard turned out to have been developed to be resistant to it before it was known about in public circles. 2. Impossible differential cryptanalysis https://en.wikipedia.org/wiki/Impossible_differential_cryptanalysis https://en.wikipedia.org/wiki/Impossible_differential_crypta... This general technique was invented and quickly broke 31 out of 32 rounds of Skipjack. Schneier wrote in 1998 "I can't imagine that the NSA would field an algorithm with 32 rounds when they could break 31, so I believe that the NSA did not know about this attack. And the cryptanalysts are still working on improving their attack, so it is possible that they will get to 32 rounds." But no one yet has.
      - makomk 13y ago
        On the other hand, you're talking about ciphers that had short enough keys that they could be brute forced by the NSA. What's more, DES was invented back in the Cold War era back when the US's main opponent, the USSR, had better mathematicians but worse computing hardware, so making sure it was as secure as thwe number of bits gave the NSA an advantage. (Skipjack was just a fiasco full stop.)
    - sesqu 13y ago
      I don't have sources handy, but I think I remember reading about several such cases from the 60's or so. They didn't really make use of the discoveries back then.
dfc 13y ago
Are you trying to get picked up by Shit HN says?
rgbrenner 13y ago
No. Titan is not fast enough to brute force AES128. All of the computers in the world put together are not fast enough. If you assume: Every person on the planet owns 10 computers. There are 7 billion people on the planet. Each of these computers can test 1 billion key combinations per second. On average, you can crack the key after testing 50% of the possibilities. Then the earth's population can crack one encryption key in 77,000,000,000,000,000,000,000,000 years! If you want to decode AES, you either need the key or find a weakness in the algo. http://www.eetimes.com/design/embedded-internet-design/4372428/How-secure-is-AES-against-brute-force-attacks- http://www.eetimes.com/design/embedded-internet-design/43724...
- mikegioia 13y ago
  Well, if they are storing all internet traffic, then they would have a pretty large sample of documents/packets encrypted using the same private keys. I don't think it's unreasonable to think that Titan could be leveraging this when trying to decode. Also, I didn't say "brute force", I said "decode".
  - marshray 13y ago
    If you can "decode" more efficiently than you can "brute force", then you have an "attack on AES".
  - deleted 13y ago
    [deleted]

betterunix 13y ago

I doubt that they are decoding AES, except perhaps for the highest-value targets. I would guess that that computing power is a shared resource, not something that can be dedicated to a single task like that. They are probably using it for numerous data mining applications, probably a lot of traffic analysis, some signal processing, etc. Even if the NSA has the resources needed to crack AES128, those resources would almost certainly be better used on other tasks.

marshray 13y ago
I agree. There is no known attack on AES-128 which comes anywhere close to the capability of any known supercomputer within any reasonable time period. Except maaaybe the aggregate computing power of the entire PlayStation Network for a long long time. I haven't run the numbers for AES. EDIT: Yeah, no way without an algorithmic breakthrough.
- jacquesm 13y ago
  There is no publicly known attack, it is possible that there are undisclosed vulnerabilities in AES-128 that the NSA is aware of today. Is there any precedent for a weakness like that where an agency like the NSA was already aware of a weakness before it became public?
  - marshray 13y ago
    A couple of cases come to mind where the NSA is seemed to demonstrate superior awareness of cryptanalytic attacks. But note that in neither case did the NSA recommend the use of a cipher that was weaker than the number of bits on the label. 1. Differential Cryptanalysis https://en.wikipedia.org/wiki/Data_Encryption_Standard#NSA.27s_involvement_in_the_design https://en.wikipedia.org/wiki/Data_Encryption_Standard#NSA.2... A general technique, but the DES standard turned out to have been developed to be resistant to it before it was known about in public circles. 2. Impossible differential cryptanalysis https://en.wikipedia.org/wiki/Impossible_differential_cryptanalysis https://en.wikipedia.org/wiki/Impossible_differential_crypta... This general technique was invented and quickly broke 31 out of 32 rounds of Skipjack. Schneier wrote in 1998 "I can't imagine that the NSA would field an algorithm with 32 rounds when they could break 31, so I believe that the NSA did not know about this attack. And the cryptanalysts are still working on improving their attack, so it is possible that they will get to 32 rounds." But no one yet has.
    - makomk 13y ago
      On the other hand, you're talking about ciphers that had short enough keys that they could be brute forced by the NSA. What's more, DES was invented back in the Cold War era back when the US's main opponent, the USSR, had better mathematicians but worse computing hardware, so making sure it was as secure as thwe number of bits gave the NSA an advantage. (Skipjack was just a fiasco full stop.)
  - sesqu 13y ago
    I don't have sources handy, but I think I remember reading about several such cases from the 60's or so. They didn't really make use of the discoveries back then.

dfc 13y ago

Are you trying to get picked up by Shit HN says?

rgbrenner 13y ago

No. Titan is not fast enough to brute force AES128. All of the computers in the world put together are not fast enough. If you assume: Every person on the planet owns 10 computers. There are 7 billion people on the planet. Each of these computers can test 1 billion key combinations per second. On average, you can crack the key after testing 50% of the possibilities. Then the earth's population can crack one encryption key in 77,000,000,000,000,000,000,000,000 years! If you want to decode AES, you either need the key or find a weakness in the algo. http://www.eetimes.com/design/embedded-internet-design/4372428/How-secure-is-AES-against-brute-force-attacks- http://www.eetimes.com/design/embedded-internet-design/43724...

mikegioia 13y ago
Well, if they are storing all internet traffic, then they would have a pretty large sample of documents/packets encrypted using the same private keys. I don't think it's unreasonable to think that Titan could be leveraging this when trying to decode. Also, I didn't say "brute force", I said "decode".
- marshray 13y ago
  If you can "decode" more efficiently than you can "brute force", then you have an "attack on AES".
- deleted 13y ago
  [deleted]