Assume passwords are selected from four-character combinations of 26 alphabetic characters. Assume an adversary is able to attempt passwords at a rate of one per second. a. Assuming no feedback to the adversary until each attempt has been completed, what is the expected time to discover the correct password b. Assuming feedback to the adversary flagging an error as each incorrect character is entered, what is the expected time to discover the correct password?

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Assume passwords are selected from four-character combinations of 26 alphabetic characters. Assume an adversary is able to attempt passwords at a rate of one per second.

a. Assuming no feedback to the adversary until each attempt has been completed, what is the expected time to discover the correct password

b. Assuming feedback to the adversary flagging an error as each incorrect character is entered, what is the expected time to discover the correct password?

Expert Solution
Step 1

Password length is 4 characters.

And each character can be any of the 26 alphabets.

Rate of attempting the password is one per second.

This means one password is checked in one second.

This means we have :

26^4 = 456976  possible passwords.

 

 

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