Cryptography and Encryption
Cryptography and encryption are fundamental concepts in cybersecurity, used to
secure communication, protect sensitive information, and ensure data integrity.
They are essential tools for maintaining privacy and safeguarding digital assets in
an increasingly interconnected world.
1. What is Cryptography?
Cryptography is the science of securing information by converting it into an
unreadable format, known as ciphertext. Only authorized parties with the correct
decryption key can transform ciphertext back into its original, readable form
(plaintext).
Key Objectives of Cryptography:
1. Confidentiality: Ensuring only intended recipients can access the
information.
2. Integrity: Preventing unauthorized alterations to data.
3. Authentication: Verifying the identity of the communicating parties.
4. Non-Repudiation: Ensuring a sender cannot deny sending a message.
2. What is Encryption?
Encryption is a technique within cryptography that involves encoding information
to make it inaccessible to unauthorized users.
How Encryption Works:
1. Encryption Algorithm: A mathematical process used to encode data.
2. Encryption Key: A secret value used in the algorithm to transform plaintext
into ciphertext.
3. Decryption Key: A secret value (often the same or related to the encryption
key) used to convert ciphertext back into plaintext.
, Example:
Plaintext: "Hello, World!"
Ciphertext: "Khoor, Zruog!" (encrypted using a simple Caesar cipher)
3. Types of Cryptography
Cryptography is broadly categorized into three types based on the key used for
encryption and decryption:
a. Symmetric Key Cryptography
Definition: Both the sender and receiver use the same key for encryption
and decryption.
Example: Advanced Encryption Standard (AES).
Advantages:
o Faster than asymmetric encryption.
o Suitable for encrypting large volumes of data.
Challenges:
o Securely sharing the key between parties can be difficult.
b. Asymmetric Key Cryptography
Definition: Uses a pair of keys – a public key (for encryption) and a private
key (for decryption).
Example: RSA (Rivest-Shamir-Adleman).
Advantages:
o No need to share private keys.
o Ideal for secure communication over the internet.
Challenges:
o Slower than symmetric encryption.
o Computationally intensive.
c. Hash Functions
Definition: Converts data into a fixed-length string, called a hash, which
cannot be reversed.
Cryptography and encryption are fundamental concepts in cybersecurity, used to
secure communication, protect sensitive information, and ensure data integrity.
They are essential tools for maintaining privacy and safeguarding digital assets in
an increasingly interconnected world.
1. What is Cryptography?
Cryptography is the science of securing information by converting it into an
unreadable format, known as ciphertext. Only authorized parties with the correct
decryption key can transform ciphertext back into its original, readable form
(plaintext).
Key Objectives of Cryptography:
1. Confidentiality: Ensuring only intended recipients can access the
information.
2. Integrity: Preventing unauthorized alterations to data.
3. Authentication: Verifying the identity of the communicating parties.
4. Non-Repudiation: Ensuring a sender cannot deny sending a message.
2. What is Encryption?
Encryption is a technique within cryptography that involves encoding information
to make it inaccessible to unauthorized users.
How Encryption Works:
1. Encryption Algorithm: A mathematical process used to encode data.
2. Encryption Key: A secret value used in the algorithm to transform plaintext
into ciphertext.
3. Decryption Key: A secret value (often the same or related to the encryption
key) used to convert ciphertext back into plaintext.
, Example:
Plaintext: "Hello, World!"
Ciphertext: "Khoor, Zruog!" (encrypted using a simple Caesar cipher)
3. Types of Cryptography
Cryptography is broadly categorized into three types based on the key used for
encryption and decryption:
a. Symmetric Key Cryptography
Definition: Both the sender and receiver use the same key for encryption
and decryption.
Example: Advanced Encryption Standard (AES).
Advantages:
o Faster than asymmetric encryption.
o Suitable for encrypting large volumes of data.
Challenges:
o Securely sharing the key between parties can be difficult.
b. Asymmetric Key Cryptography
Definition: Uses a pair of keys – a public key (for encryption) and a private
key (for decryption).
Example: RSA (Rivest-Shamir-Adleman).
Advantages:
o No need to share private keys.
o Ideal for secure communication over the internet.
Challenges:
o Slower than symmetric encryption.
o Computationally intensive.
c. Hash Functions
Definition: Converts data into a fixed-length string, called a hash, which
cannot be reversed.
