Once a user authenticates, it is sometimes desirable to have the program keep this authentication information available, so that we do not need to bother the user to authenticate repeatedly.8 a....

Once a user authenticates, it is sometimes desirable to have the program keep this authentication information available, so that we do not need to bother the user to authenticate repeatedly.8

a. Devise a method for a program to cache authentication information, where the information is stored in a different form each time it's cached.

b. Is there any security advantage to your approach in part a, as compared to simply storing the information the same each time?