From the course: CISSP Cert Prep (2021): 3 Security Architecture and Engineering

Unlock the full course today

Join today to access over 22,600 courses taught by industry experts or purchase this course individually.

Cryptographic math

Cryptographic math

From the course: CISSP Cert Prep (2021): 3 Security Architecture and Engineering

Start my 1-month free trial

Cryptographic math

“

- [Instructor] Math plays a central role in cryptography. You won't find complex mathematical questions on the exam, but you should be familiar with some of the basic terms and concepts that support cryptography. First, many cryptographic algorithms use the Exclusive Or operation to combine plain text and cipher text with cryptographic keys. The Exclusive Or operation, which is often abbreviated X-O-R or XOR, is a logical operation that is true when one, and only one, of the inputs is true. Let's take a look at the truth table for the XOR operation. Here we have two variables, X and Y, and then the Exclusive Or of those two variables, which is represented by the symbol that you see here on the screen, a plus with a circle around it. If we have two inputs, X and Y, and they're both false, then neither one of those is true and X exclusive or Y is false. If X is true and Y is false, then exactly one of the inputs is…

Contents