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Posts: 30 | Thanked: 14 times | Joined on Mar 2011 @ Romania
#2801
Originally Posted by Cod3rror View Post
Are you guys still on this ElGamal BS?

You will win nokia's already dead garbage phone that they won't be able to sell, not a noble prize.
u just don't know when to stop, do you? you were fun for a while, then annoying, but now you're just pathetic, in my oppinion! u really can't find something better to spend your time on??

to answer your question, yes, still on el gamal, because it's f***ing awesome to try to solve something like this! it's not about the n9 anymore (at least, not for me), but about the thrill! but that's something you'll never understand, I guess...
 
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Posts: 226 | Thanked: 195 times | Joined on Nov 2009 @ Malaysia
#2802
Just to update you guys, there's been invites going around to a "preview" of the N9 in Malaysia sometime soon - within the next couple of weeks. Judging from the amount of time it took for Nokia Malaysia to organize something like this for the N900 (6 months after official launch), I would assume that the N9 can't be that far off - right on track for the late August/early September launch date that's been going around on the boards for awhile.
 
Posts: 52 | Thanked: 74 times | Joined on Jun 2011
#2803
ElGamal Example (explained easier)

This scheme requires several variables.

a is a secret key less than the value of p. We will assume it is 304 since p must be greater than it.
g is the generator variable. Nokia has told us its value is 10.
p is a large prime number that Nokia have told us is >304.
For our situation, p is the most important. It is a prime number that must have 'g' as a primitive root.
For fun, we will select 2789.
m is our encrypted message (if there is one) that has to be less than p. For fun we'll choose 832 (from taxi)
k is a prime number used for encrypting the message. It also has the condition it must be less than p and gcd(k, p − 1) = 1. For fun, we will choose 15 (from truck).

So let's do it.

Generate Public Key

p = 2789; g = 10; a = 304
g^a % p = 10^304 (% 2789) ≡ 1161

Now we have what is known as a 'public key' (p, g, g^a%p).
The public key is P = (p ← 2789, g ← 10, g^a%p ← 1161), the secret key is a (304).

Encrypt Message

Next, we encrypt a message m = 832 as follows:
k = 15
γ = 10^15 (% 2789) ≡ 1063
δ ≡ 832 x 1161^15 (% 2789) ≡ 181
c = (γ ← 1063, δ ← 181)

The ciphertext, c, is then sent to the recipient.

Decrypt Message

The recipient can then calculate m from this. The message is calculated by:
m ≡ 1063^(2789-1-304) x 181 ≡ (1063^2484) x 181 (% 2789) ≡ 832

In summary -- to get your 6 digits for the competition:
Generating Public Key
<p><10><10^a % p> (6 digits)

In this situation, p is most likely 3 digits. Also, a or y is likely 15 (where else would it be used?)
This means you can get p from the list below:
313, 337, 367, 379, 383, 389, 419, 433, 461, 487, 491, 499, 503, 509, 541, 571, 577, 593, 619, 647, 659, 701, 709, 727, 743, 811, 821, 823, 857, 863, 887, 937, 941, 953, 971, 977, 983.

Generating Cipher Key
<10^k % p><m*(10^a%p)^k %p> (6 digits)

In this situation, p is most likely 4 digits.
This means Nokia has given us the p from the 'colors on the wall'.

Last edited by recluse; 2011-07-28 at 12:43.
 

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Posts: 66 | Thanked: 27 times | Joined on Jul 2011
#2804
Originally Posted by recluse View Post
3.5 Example
Generation of a key: p and a are randomly generated, g is a primitive root of p appropriate.
p = 2357
g = 2
a = 1751
g^a mod p = 2^1751 (mod 2357) ≡1185

The public key is now P = (p ← 2357, g ← 2, g^a ← 1185), the secret key is a.
Encrypt a message m = 2035 is as follows (k is randomly chosen):
k = 1520
γ = 2^1520 (mod 2357) ≡ 1430
δ ≡ 2035 x 1185^1520 (mod 2357) ≡ 697
c = (γ ← 1430, δ ← 697)
The ciphertext, c, is then sent to the recipient. We can then calculate m from this. the message is calculated by:
m ≡ 1430^(2357-1-1751) x 697 ≡ 872 x 697 (mod 2357) ≡ 2035
Damn man, looks like you're solving the world hunger!
__________________
Free yourself from nokia's morlock cave, discover the future, today: iPhone!
 

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Posts: 2 | Thanked: 0 times | Joined on Jul 2011
#2805
Originally Posted by aikipy View Post
I know that now but last night, before I watched the movie again, I thought it was a wall, not a truck, so the idea kinda got stuck in my mind
Where is the truck? This may be dumb..
 
Posts: 54 | Thanked: 11 times | Joined on Jul 2011
#2806
Originally Posted by biatch0 View Post
Just to update you guys, there's been invites going around to a "preview" of the N9 in Malaysia sometime soon - within the next couple of weeks. Judging from the amount of time it took for Nokia Malaysia to organize something like this for the N900 (6 months after official launch), I would assume that the N9 can't be that far off - right on track for the late August/early September launch date that's been going around on the boards for awhile.
@biatch0
im fr msia too. where/when's the n9 preview? btw is the invites private oni?
thx..
 
Posts: 130 | Thanked: 57 times | Joined on Jul 2010 @ UK
#2807
Originally Posted by recluse View Post
ElGamal Example
p is a prime, g is a primitive root of p, a is a random secret number.
p = 2789; g = 10; a = 2351
g^a % p = 10^2351 (% 2789) ≡1980

Now we have what is known as a 'public key' (p, g, g^a%p).
The public key is P = (p ← 2789, g ← 10, g^a%p ← 1980), the secret key is a (2351).

Next, we encrypt a message m = 832 as follows (k is randomly chosen, m has to be less than p):
k = 1520
γ = 10^1520 (% 2789) ≡ 2300
δ ≡ 832 x 1980^1520 (% 2789) ≡ 2271
c = (γ ← 2300, δ ← 2271)

The ciphertext, c, is then sent to the recipient.

The recipient can then calculate m from this. The message is calculated by:
m ≡ 2300^(2789-1-2351) x 2271 ≡ (2300^437) x 2271 (% 2789) ≡ 832


<head ache>
 
Posts: 30 | Thanked: 14 times | Joined on Mar 2011 @ Romania
#2808
Originally Posted by notGeekyEnough View Post
Where is the truck? This may be dumb..
in the second video. it almost blends in with the wall
 

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Posts: 52 | Thanked: 74 times | Joined on Jun 2011
#2809
When looking for 6 digit numbers, it will either be the public key, the cipher text or, possibly, p.

Possible primes, p > 304, with a prime root of 10:
313, 337, 367, 379, 383, 389, 419, 433, 461, 487, 491, 499, 503, 509, 541, 571, 577 ...

Last edited by recluse; 2011-07-28 at 11:13.
 

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Posts: 2 | Thanked: 0 times | Joined on Jul 2011
#2810
bye bye #n9seconds.. My head is aching. thanks to you. I have watched the video zillion times. Did not complete my office deadlines. Have a deliverable tomorrow.

this has become too geeky now..

Thank god, there were only 6 ads and each for 9 seconds...
 
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disapoint, eflop, epic win!, laggy interface, n9 rox, so much win, wateriswet, who cares, whyyyyy??????


 
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