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What are some innovative encryption methods?

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Re: What are some innovative encryption methods?

#21

Post by mseebach »

hawski wrote: post #18
benwilber0 wrote: post #13

Not exactly "innovative", since it's one of the oldest encryption methods, but the One-Time Pad[0] is considered "perfect encryption" and proven to be unbreakable. The mere possibility of unbreakable encryption could fill up a thesis by itself. [0] http://www.cs.utsa.edu/~wagner/laws/pad.html edit to clarify: "unbreakable" is the wrong word, since it could be brute-forced with enough time and energy, like any encrypt…

I was wondering if using randomly generated shared 1GB or so file as a kind of one-time pad would be useful. Xor data with it using it as circular buffer, do messages must be of the same length or it will go out of sync.

If you reuse your pad, you're vulnerable to frequency analysis, which is literally the oldest trick in the book. You might as well send in plaintext.

Re: What are some innovative encryption methods?

#23

Post by sounds »

mseebach wrote: post #20
benwilber0 wrote: post #13

Not exactly "innovative", since it's one of the oldest encryption methods, but the One-Time Pad[0] is considered "perfect encryption" and proven to be unbreakable. The mere possibility of unbreakable encryption could fill up a thesis by itself. [0] http://www.cs.utsa.edu/~wagner/laws/pad.html edit to clarify: "unbreakable" is the wrong word, since it could be brute-forced with enough time and energy, like any encrypt…

The problem, of course, is that you're just flipping the problem around. For every bit you need to send A->B, you need to first securely send a bit B->A (the pad). That's practical for a number of applications, and obviously not for many others.

Combined with envelope keys it can be effective for many applications.

An envelope key is a securely, randomly generated key used to encrypt the large payload. Then the envelope key (much smaller than the payload) can be encrypted using a one time pad.

The result is that the precious bits of encryption provided by the one time pad are used up at a predictable rate.

Guessing the envelope key is more probable than guessing the one time pad key, but that only breaks a single message's encryption.

Re: What are some innovative encryption methods?

#24

Post by _8j50 »

Identity based encryption.

https://en.wikipedia.org/wiki/ID-based_encryption

"Identity-based systems allow any party to generate a public key from a known identity value such as an ASCII string. A trusted third party, called the Private Key Generator (PKG), generates the corresponding private keys...."

I think it's innovative and a bit of "thinking outside the box". You do need to ultimately trust a 3rd party (same as in PKI or WOT I guess?).

Re: What are some innovative encryption methods?

#26

Post by vectorEQ »

benwilber0 wrote: post #13

Not exactly "innovative", since it's one of the oldest encryption methods, but the One-Time Pad[0] is considered "perfect encryption" and proven to be unbreakable. The mere possibility of unbreakable encryption could fill up a thesis by itself. [0] http://www.cs.utsa.edu/~wagner/laws/pad.html edit to clarify: "unbreakable" is the wrong word, since it could be brute-forced with enough time and energy, like any encrypt…

this is the only fully 100% proven crypto method. rest is 'weak' , only saved by lack of computing power, not actual difficulty of algorithm. problem with otp is dat if you can send the pad... you mightswell not use it. as the pad needs to be sent over secure channel. So it's unbreakable, but also impractical.

Re: What are some innovative encryption methods?

#27

Post by [deleted] »

benwilber0 wrote: post #13

Not exactly "innovative", since it's one of the oldest encryption methods, but the One-Time Pad[0] is considered "perfect encryption" and proven to be unbreakable. The mere possibility of unbreakable encryption could fill up a thesis by itself. [0] http://www.cs.utsa.edu/~wagner/laws/pad.html edit to clarify: "unbreakable" is the wrong word, since it could be brute-forced with enough time and energy, like any encrypt…

[deleted]

Re: What are some innovative encryption methods?

#28

Post by [deleted] »

vectorEQ wrote: post #26
benwilber0 wrote: post #13

Not exactly "innovative", since it's one of the oldest encryption methods, but the One-Time Pad[0] is considered "perfect encryption" and proven to be unbreakable. The mere possibility of unbreakable encryption could fill up a thesis by itself. [0] http://www.cs.utsa.edu/~wagner/laws/pad.html edit to clarify: "unbreakable" is the wrong word, since it could be brute-forced with enough time and energy, like any encrypt…

this is the only fully 100% proven crypto method. rest is 'weak' , only saved by lack of computing power, not actual difficulty of algorithm. problem with otp is dat if you can send the pad... you mightswell not use it. as the pad needs to be sent over secure channel. So it's unbreakable, but also impractical.

[deleted]

Re: What are some innovative encryption methods?

#29

Post by Someone »

sounds wrote: post #23
mseebach wrote: post #20

Earlier quoted context omitted.

The problem, of course, is that you're just flipping the problem around. For every bit you need to send A->B, you need to first securely send a bit B->A (the pad). That's practical for a number of applications, and obviously not for many others.

Combined with envelope keys it can be effective for many applications. An envelope key is a securely, randomly generated key used to encrypt the large payload. Then the envelope key (much smaller than the payload) can be encrypted using a one time pad. The result is that the precious bits of encryption provided by the one time pad are used up at a predictable rate. Guessing the envelope key is more probable than gues…

If you use good encryption and a reasonable key size, that’s good in practice, but theoretically, that’s a lot less secure than a one time pad.

An attacker can ‘simply’ try all possible keys and use statistics to filter out those that look like natural language.

If the encrypted text is large enough, chances are you will be left with only one plausible plaintext.

Also, AFAIK, we don’t know whether good encryption using a key much shorter than the plaintext, in the sense that an attacker can’t use statistics on the encrypted text to learn something about the key, exists at all.

Re: What are some innovative encryption methods?

#30

Post by hawski »

mseebach wrote: post #21
hawski wrote: post #18

Earlier quoted context omitted.

I was wondering if using randomly generated shared 1GB or so file as a kind of one-time pad would be useful. Xor data with it using it as circular buffer, do messages must be of the same length or it will go out of sync.

If you reuse your pad, you're vulnerable to frequency analysis, which is literally the oldest trick in the book. You might as well send in plaintext.

How easy would it be if you would go through the entire 1GB and only then from the beginning? I guess it is a question of how big messages are.
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