Unlocking the Secrets of Cryptography: An Overview of CEH Module 20
In the digital age, securing information is paramount. Cryptography, the practice of converting readable data into unreadable formats to protect its confidentiality, integrity, authentication, and nonrepudiation, is a cornerstone of cybersecurity. This article delves into the essential concepts, types, and algorithms of cryptography as covered in Module 20 of the Certified Ethical Hacker (CEH) course.
Core Concepts of Cryptography
Cryptography ensures that information is accessible only to those authorized, prevents unauthorized alterations, verifies the authenticity of data, and ensures that senders cannot deny their communications. These objectives are achieved through two primary types of cryptography: symmetric and asymmetric encryption.
Types of Cryptography
- Symmetric Encryption: This method uses the same key for both encryption and decryption. While faster and easier to implement, its major drawback is the secure exchange of the key between parties.
- Asymmetric Encryption: Also known as public-key cryptography, this method employs a pair of keys – a public key for encryption and a private key for decryption. This approach eliminates the need for secure key distribution but requires more processing power.
Key Encryption Algorithms
- Data Encryption Standard (DES): Once the gold standard for encryption, DES uses a 56-bit key but is now considered vulnerable due to advancements in computing power.
- Triple DES (3DES): An enhancement of DES, 3DES applies the DES algorithm three times with different keys, providing a higher level of security.
- Advanced Encryption Standard (AES): Widely adopted for its efficiency and robustness, AES supports key sizes of 128, 192, and 256 bits and is used in various applications, from securing financial transactions to government communications.
- RC4, RC5, and RC6: These are a series of symmetric-key algorithms known for their speed and simplicity. RC4 is a stream cipher, while RC5 and RC6 are block ciphers with variable key sizes and rounds.
- Blowfish and Twofish: Both are symmetric block ciphers designed to replace DES. Blowfish is known for its speed, while Twofish offers flexibility in key scheduling and implementation.
- Threefish: Part of the Skein hash function, Threefish is a tweakable block cipher designed for efficiency and security without the use of S-boxes, making it resistant to cache timing attacks.
Government Access to Keys (GAK)
GAK mandates that cryptographic keys be disclosed to government agencies, allowing them to monitor communications for national security purposes. This raises concerns about privacy and the secure handling of these keys by government entities.
Conclusion
Cryptography is a vital tool in the arsenal of cybersecurity professionals, providing the means to protect sensitive information from unauthorized access and tampering. As technology evolves, so too do the methods and algorithms used to secure our digital world, making continuous learning and adaptation essential for those in the field.
With my study notes I have create a set of 7 flashcards that can be accessed here: Module 20 – Flash Cards
I have also created this visual Mind map: Module 20 – Mindmap
If you have any questions or any feedback feel free to comment or leave a message on the homepage as that will send directly to me!
Thanks for reading!
