b Consider the number of possible passwords calculated in Part A. Is a password based on your name secure?
A
a 24
B
b No, see solution.
Practice makes perfect
a We want to find the number of permutations that are possible using each letter of the word Lena only once.
Since each letter occurs only once, we will use the Permutation Notation to find the number of permutations.
_nP_r = n!/(n-r)!
We want to arrange 4 out of 4 letters at a time. Therefore, let's substitute r= 4 and n= 4 into the formula to find the number of permutations.
Lena can generate 24 unique passwords that use each letter of her name only once.
b We are asked whether creating a password based on your name is a good idea. Let's consider the example of Lena. As we found in Part A, there are 24 possible passwords that can be generated when using each letter only once.
Number of Letters:& 4
Number of Passwords:& 24
Since the number of possibilities is considerably small, the password can be easily cracked. This means that the password is not secure and our account would be prone to unauthorized access.
There is a limited number of possible passwords so someone can figure it out.
Also, we often use our first or last name in the user login, which would make it even easier to crack the password. Therefore, creating a password based on our name is not a good idea.
