Modern cryptography is one of the main foundations of information security in the digital age. With increasing dependence on technology to store, send, and access data, data security becomes very important. Modern cryptography allows us to protect information from unauthorized access through engineering encryption and decryption. This article will give you an introduction to modern cryptography, its principal principles, and some of the important algorithms that are being used today.

What's Cryptography?

Cryptography is science and art to hide information so only the authorities can read it. This is done by converting (readable) messages into unreadable (cipher) shapes. The opposite process, called decryption, allows the message to return to its original form in order to be read by a legitimate recipient.

Modern cryptography is mainly based on math theory and computing techniques to ensure data security. It's different from ancient cryptography that relies on simple techniques such as letter substitution or messaging.

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Modern cryptography is based on some key principles that ensure information security, among other things:

1. Confidential: Only a valid recipient can understand encrypted messages.
2. Integrity (Integrity): Data may not be changed during transmission undetected.
3. Authentication (Authentication): Sender and recipient can confirm each other's identities.
4. Non- repudiation: Sender cannot deny sending a sent message.

Modern Cryptography Algorithm

Modern cryptography uses various algorithms to encrypt and protect data. These algorithms divide in two major categories: symmetric cryptography and asymmetric cryptography.

1. Symmetrical Cryptography

Symmetric cryptography uses the same key for encryption and decryption. That is, the sender and recipient must have the same key, which makes it efficient in computing, but it's difficult in terms of key distribution.

• Algorithm Example:
  • AES (Advanced Encryption Standard)AES is a standard symmetrical encryption that is very popular and widely used to protect digital data. This algorithm uses the length of the key 128, 192, or 256-bit, and is known to be safe because it's hard to solve even though it uses brute-force attack.
  • DES (Standard Encryption Data): DES is an encryption algorithm used widely in the past, but has been replaced by AES because of its weakness in the face of brute-force short key length (56-bit) attacks.

Symmetrical Cryptography Extensive:

• Fast and efficient to manage large amounts of data.

Lack:

• Key distribution is difficult and unsafe in large networks, because both sides must have the same key.

2. Asymmetric Cryptography

asymmetric cryptography uses two different keys: public key for encryption and private key for decryption. Public keys can be shared freely, while private keys must be kept secret. It solves the key distribution problem that's on symmetrical cryptography.

• Algorithm Example:
  • RSA (Rivest-Shamir-Adleman): RSA is a very popular asymmetrical algorithm for encryption and digital significance. This algorithm is based on difficulty of large-number factors, so it's safe to use communication that requires authentication and encryption.
  • Elliptic Curve Cryptography (ECC): ECC is the alternative to RSA that offers the same security with a shorter key, making it more efficient than computing.

Asymmetric Cryptography Extensive:

• It requires no direct exchange of keys, so it's safer in communication.

Lack:

• Slower than symmetrical cryptography.

Kriptography Hash Function

In addition to encryption and decryption, modern cryptography also involves hash functions. hash functions generate a fixed (digest) value of a changed-length input, and are used to ensure data integrity. The hash functions commonly used in cryptography include SHA- 256 and MD5.

hash functions are very important in Digital signature and authentication of message. In digital signatures, the hash of a message is generated and encrypted with the sender's private key, allowing the recipient to verify the sender's identity and make sure the message is not changed.

Modern Cryptography Application

Modern cryptography is used widely in various aspects of digital life, such as:

1. Internet Security (SSL / TLS): SSL and TLS protocols use asymmetric cryptography to secure internet communication. This is the basis of HTTPS security.
2. Authentication and Digital Signature: Cryptography used to verify the identity and validity of digital documents in financial transactions and electronic contracts.
3. Secure Data Storage: Algorithm such as AES used to encrypt data storage on hardware such as hard drives and cloud storage.
4. Blockchain and Cryptocurency: asymmetric cryptography is used in blockchain technology to ensure the security of cryptocurency transactions such as Bitcoin and Ethereum.

Conclusion

Modern crytography is a pillar of digital security in various fields, from daily communication on the Internet to financial transactions and data storage. cryptography algorithms such as AES and RSA, as well as cryptography hash functions, are essential in maintaining secrecy, integrity and information authentication. With technology progressing, cryptography will continue to be an integral part of an attempt to protect data in the digital era.

source: Stallings, W. (2016). Cryptography and Network Security: Pearson.