Hello Folks,

In this introductory blog, we will cover the answers for the “**Cryptography Basics**” room which is a part of the “**Cyber Security 101**” learning path. This room covers the basics of cryptography which secures the digital communication maintaining confidentiality, integrity and authenticity of the data. We will cover many concepts related to it such as symmetric & asymmetric cryptography, encoding and basic math behind these ciphers.

You can access the room by clicking **here**.

**Task 1 Introduction**

This task will let you know the learning objectives and prerequisites of this room. You can work on it to understand the concepts of Cryptography.

I’m ready to start learning about cryptography!

No answer needed

**Task 2 Importance of Cryptography**

**Cryptography** has become vital for every online transaction and communication as it secures our data privacy from intruders. In this section, we will understand the importance of it.

Q 2.1- What is the standard required for handling credit card information?

**A 2.1- PCI DSS**

**Task 3 Plaintext to Ciphertext**

In this task, we will explore the concepts of **Plaintext** which is considered as human readable and understandable form of data and **Ciphertext **which is non-human readable form of data. Key terms include **plaintext, ciphertext, encryption **and** decryption**.

Q 3.1- What do you call the encrypted plaintext?

**A 3.1- Ciphertext**

Q 3.2- What do you call the process that returns the plaintext?

**A 3.2- decryption**

**Task 4 Historical Ciphers**

This task presents the history of cryptography where one of the oldest algorithms called **Caesar Cipher** was built and used. This cipher is considered weak as per today’s world but now we have other ciphers to use such as **Base64, Morse Code,** etc.

Q 4.1- Knowing that XRPCTCRGNEI was encrypted using Caesar Cipher, what is the original plaintext?

**A 4.1- ICANENCRYPT**

**Task 5 Types of Encryption**

In this section, we will cover two types of encryption: **symmetric encryption** where a shared key is used for both encryption and decryption and **asymmetric encryption** where two different but relational keys are used; one for encryption and other one for decryption.

Q 5.1- Should you trust DES? (Yea/Nay)

**A 5.1- Nay**

Q 5.2- When was AES adopted as an encryption standard?

**A 5.2- 2001**

**Task 6 Basic Math**

The two fundamental mathematical operations on which most cryptographic ciphers are based are **XOR** and **modulo** operation. We can understand the concepts of it by going through this task.

Q 6.1- What’s 1001 ⊕ 1010?

**A 6.1- 0011**

Q 6.2- What’s 118613842%9091?

**A 6.2- 3565**

Q 6.3- What’s 60%12?

**A 6.3- 0**

**Task 7 Summary**

Before proceeding to the next room, make sure you have taken note of all the key terms and concepts introduced in this room.

**No answer needed**

You can check out our other blogs **here**.

Happy Pentesting!!!

Team CyberiumX