Intro to Cryptography

What is Cryptography?

By dictionary definition, Cryptography is the process of hiding or coding information so that only the person a message was intended for can read it. In our everyday lives, Cryptography is crucial to ensuring that our messages and data are secure through the use of complicated algorthms

Goals of Information Security

In the realm of information security, there are three fundamental goals, confidentiality, integrity, availability. All together, they are commonly known as the CIA triad. Authenticity and Non-Repudiation are also commonly included goals. As the focus of this section is on Cryptography, I won’t be going in-depth on availability.

Confidentiality

One of the core goals, confidentiality is all about ensuring only authorized persons can gain access to certain information. Access Control and Encryption are some ways to ensure confidentiality, but we’ll be focusing on encryption in this section

Integrity

Data Integrity ensures that data is not altered, whether it is in transit or sitting in your hard drive. Integrity is a crucial goal as we want to be sure that the file that we downloaded hasn’t been secretly tampered with, or the important data we stored in our thumbdrives hasn’t been corrupted.

Authenticity

Authenticity ensures that the data you received is truly from the person that claims to send it. In other words, it’s about validating the source or origin of the data being transmitted.

Authenticity implies Integrity: A piece of data that satisfies the requirement for authenticity, will also satisfy the requirement for integrity. However, data that satisfies the requirement for integrity might not be authentic, even though the data itself might not be modified, you can’t be sure who sent it.

Non-repudiation

When two people engage in a transaction, it’s possible for one side to claim that they never took part in the transaction. The authenticity of the transactions is being “repudiated”. Non-repudiation ensures that this scenario does not happen, basically no “taksies backsies”.

Conclusion

As we wrap up the first chapter, these goals might seem like common sense, however they are fundamental concepts to learn if we want to dive deeper into information security. In the next few chapters, we’ll be going more in-depth into the technical details and implementation.

Created: March 13, 2024

Last Edited: March 13, 2024