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You are doing a Diffie-Hellman-Merkle key exchange with Aisha using generator 7 and prime 437. Your secret number is 227. Aisha sends you the value 308. Determine the shared secret key.

User Conrad Clark
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1 Answer

25 votes
25 votes

Answer:

382^2 mod

Explanation:

To determine the shared secret key, we need to use the formula (g^a mod p)^b mod p = (g^b mod p)^a mod p, where g is the generator, p is the prime, a is our secret number, and b is the value sent by Aisha. Plugging in the values, we get (7^227 mod 437)^308 mod 437 = (7^308 mod 437)^227 mod 437.

To solve for the shared secret key, we first need to calculate (7^308 mod 437). This can be done by raising 7 to the 308th power and then taking the remainder when divided by 437. We can do this by repeatedly squaring 7 and taking the remainder each time. This results in the following sequence:

7^2 mod 437 = 49

7^4 mod 437 = 161

7^8 mod 437 = 267

7^16 mod 437 = 9

7^32 mod 437 = 49

7^64 mod 437 = 161

7^128 mod 437 = 267

7^256 mod 437 = 9

7^512 mod 437 = 49

Since 512 is greater than 308, we can stop here and use the value 49 as the result of 7^308 mod 437. We can now plug this value into the formula to calculate the shared secret key: (49^227 mod 437)^308 mod 437 = (49^308 mod 437)^227 mod 437.

To solve for the shared secret key, we need to find the value of 49^308 mod 437. This can be done using the same method as before, by repeatedly squaring 49 and taking the remainder each time. This results in the following sequence:

49^2 mod 437 = 67

49^4 mod 437 = 382

49^8 mod 437 = 221

49^16 mod 437 = 67

49^32 mod 437 = 382

49^64 mod 437 = 221

49^128 mod 437 = 67

49^256 mod 437 = 382

Since 256 is greater than 308, we can stop here and use the value 382 as the result of 49^308 mod 437. We can now plug this value into the formula to calculate the shared secret key: 382^227 mod 437 = 382^227 mod 437.

To find the shared secret key, we need to calculate 382^227 mod 437. This can be done using the same method as before, by repeatedly squaring 382 and taking the remainder each time. This results in the following sequence:

User Ashwin Bande
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