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changed references to Rfc2898DeriveBytes objects to PBKDF2, improved formatting etc.
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otus
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Importance of salt while generatingwhen deriving an encryption key

I'm very curious to know this and a bit confuseconfuses too, Case1:suppose, I have two files encrypted using AES-128bit ( using same password, same salt but different Rfc2898DeriveBytes objects). If an attacker does brute force attack (imagining that he finishes this) to crack the keys, I'm guessing he needs to run the attack once to get those 2 keys.

Case2:Now, If I encrypt the files using AES-128bit (using same password but different salts and different Rfc2898DeriveBytes objects), will it make the attacker run brute force twice? if the answer is yes, then why? changing the salt doesn't change the number of possible keys (2^128).

  1. Suppose, I have two files encrypted using AES-128bit with keys PBKDF2-derived from the same password and the same salt. If an attacker does brute force attack (imagining that he finishes this) to crack the keys, I'm guessing he needs to run the attack once to get those 2 keys.

  2. Now, if I encrypt the files using AES-128bit with keys PBKDF2-derived from the same password and a different salt, will it make the attacker run brute force twice? If the answer is yes, then why? Changing the salt doesn't change the number of possible keys $2^{128}$.

If the answer is no then, in both cases the number of possible keys are 2^128$2^{128}$. So, Whatwhat difference does it make if the salt is different?

Importance of salt while generating key

I'm very curious to know this and a bit confuse too, Case1:suppose, I have two files encrypted using AES-128bit ( using same password, same salt but different Rfc2898DeriveBytes objects). If an attacker does brute force attack (imagining that he finishes this) to crack the keys, I'm guessing he needs to run the attack once to get those 2 keys.

Case2:Now, If I encrypt the files using AES-128bit (using same password but different salts and different Rfc2898DeriveBytes objects), will it make the attacker run brute force twice? if the answer is yes, then why? changing the salt doesn't change the number of possible keys (2^128).

If the answer is no then, in both cases the number of possible keys are 2^128. So, What difference does it make if the salt is different?

Importance of salt when deriving an encryption key

I'm very curious to know this and a bit confuses too:

  1. Suppose, I have two files encrypted using AES-128bit with keys PBKDF2-derived from the same password and the same salt. If an attacker does brute force attack (imagining that he finishes this) to crack the keys, I'm guessing he needs to run the attack once to get those 2 keys.

  2. Now, if I encrypt the files using AES-128bit with keys PBKDF2-derived from the same password and a different salt, will it make the attacker run brute force twice? If the answer is yes, then why? Changing the salt doesn't change the number of possible keys $2^{128}$.

If the answer is no then, in both cases the number of possible keys are $2^{128}$. So, what difference does it make if the salt is different?

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Giliweed
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Importance of salt while generating key

I'm very curious to know this and a bit confuse too, Case1:suppose, I have two files encrypted using AES-128bit ( using same password, same salt but different Rfc2898DeriveBytes objects). If an attacker does brute force attack (imagining that he finishes this) to crack the keys, I'm guessing he needs to run the attack once to get those 2 keys.

Case2:Now, If I encrypt the files using AES-128bit (using same password but different salts and different Rfc2898DeriveBytes objects), will it make the attacker run brute force twice? if the answer is yes, then why? changing the salt doesn't change the number of possible keys (2^128).

If the answer is no then, in both cases the number of possible keys are 2^128. So, What difference does it make if the salt is different?