What is Polymorphic Encryption?

Instructor: David Gloag
Encryption is an important topic these days, with the exploding use of the Internet. In this lesson, we'll take a look at a specific type, polymorphic, what it is, some of its advantages, and disadvantages.

The Need for Security

We live in a world where there is a need for significant security. You just have to think about your country's government, or their associated military, to get an idea. They are communicating over vast distances, and about topics that could literally shake the foundations of our world. But when you think about it a little further, you quickly realize that this kind of security affects us closer to home. Your bank and credit card information, or your Internet purchases, are protected at this level. Technologies like encryption, and more specifically, polymorphic encryption, exist exactly for that purpose.

What is Encryption?

Encryption is a conversion process. It takes information in one form (usually human-readable), and converts it to another (not usually human-readable). It is mathematically based, often requiring the calculation of complex values. A piece of external information, known as a key, is used to perform this conversion and adds a random element to the process. There are several different types of encryption, and they are used for many things. Common examples include protecting sensitive political and military communications, storing account information for bank and credit cards, and hiding the password to your personal computer. Chances are, you don't even know it's there.

What is Polymorphic Encryption?

In most forms of encryption, the method or algorithm remains the same each time it is used, you encrypt then decrypt, and a key provides variation and uniqueness. In polymorphic encryption, the algorithm, the encryption/decryption pair, changes each time it is used. It is important to note that for the same key, the outcome of the encryption remains the same. Let's look at a simple example. Say our encryption algorithm has two parts, first it splits the input value into pieces, and second, it adds them together to get a final result. Further, let's say the end result of the encryption is 7 for a specific key. This gives rise to a number of variations:

  • 1 + 1 + 1 + 1 + 1 + 1 + 1 = 7
  • 1 + 1 + 1 + 1 + 1 + 2 = 7
  • 1 + 1 + 1 + 1 + 3 = 7
  • 1 + 1 + 1 + 2 + 2 = 7
  • 1 + 1 + 1 + 4 = 7
  • 1 + 1 + 2 + 3 = 7
  • 1 + 2 + 2 + 2 = 7
  • 1 + 1 + 5 = 7
  • 1 + 3 + 3 = 7
  • 1 + 2 + 4 = 7
  • 1 + 6 = 7
  • 2 + 5 = 7
  • 3 + 4 = 7

Each arrives at the same output, 7, but they do it in a different fashion each time. This is exactly what polymorphic encryption does, albeit in a more significant fashion.

What are the Advantages of Polymorphic Encryption?

Polymorphic encryption provides two main advantages. First, it changes the algorithm each time, so the algorithm becomes more difficult to recognize. Think of the example above. If you knew that the input value was broken up into two pieces, would it be easier to spot in memory than if the number of pieces varied? Definitely! And second, it becomes harder to decrypt because there is no discernable relationship between the algorithm and the results. This makes it harder for certain types of attacks that exploit this relationship. Again, think of the example. The number of operands in the equation changes from seven to two. Would that make it harder to determine the pattern might be, and what the relationship between the operands is? Absolutely!

To unlock this lesson you must be a Study.com Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use Study.com

Become a Study.com member and start learning now.
Become a Member  Back
What teachers are saying about Study.com
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? Study.com has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create an account