to the sender.
Introduction to Cryptography
Cryptography is a branch of computer science that deals with the secure transmission of information. It enables us to protect data from unauthorized access, manipulation, and disclosure. In this worksheet, we will explore the basics of cryptography and practice some related problems.
What is Cryptography?
Cryptography is the science of using mathematics and computer algorithms to secure information. It is used to protect data from unauthorized access, manipulation, and disclosure. Cryptography can be used to protect data in transit (when it is being sent from one place to another) and data at rest (when it is stored on a device).
Types of Cryptography
There are two main types of cryptography: symmetric and asymmetric.
Symmetric Cryptography
Symmetric cryptography is also known as secret key cryptography. It uses a single key to both encrypt and decrypt data. This means that the sender and receiver of the data must both have the same key.
Asymmetric Cryptography
Asymmetric cryptography is also known as public key cryptography. It uses two different keys: a public key and a private key. The public key is used to encrypt data, and the private key is used to decrypt it. This means that only the person with the private key can decrypt the data.
Cryptographic Algorithms
Cryptographic algorithms are mathematical formulas used to encrypt and decrypt data. Some of the most commonly used algorithms are AES, RSA, and SHA.
AES
Advanced Encryption Standard (AES) is a symmetric cryptographic algorithm used to encrypt and decrypt data. It is one of the most secure algorithms used today.
RSA
RSA is an asymmetric cryptographic algorithm used to encrypt and decrypt data. It is based on the difficulty of factoring large numbers.
SHA
Secure Hash Algorithm (SHA) is a cryptographic algorithm used to generate a digital fingerprint of data. It is used to verify that data has not been modified.
Practice Problems
What is the difference between symmetric and asymmetric cryptography?
What is the purpose of a cryptographic algorithm?
What is an example of a symmetric cryptographic algorithm?
What is an example of an asymmetric cryptographic algorithm?
What is an example of a cryptographic algorithm used to generate a digital fingerprint?
Alice wants to send a secure message to Bob. What type of cryptography should she use?
Bob wants to send a secure message to Alice. What type of cryptography should he use?
Alice and Bob both want to send secure messages to each other. What type of cryptography should they use?
Alice and Bob both want to store sensitive data on their computer. What type of cryptography should they use?
Alice wants to send a secure message to Bob, but Bob does not have the same key as Alice. What type of cryptography should Alice use?