What Is Encryption: Understanding How It Works, Different Types, and More

What Is Encryption: Understanding How It Works, Different Types, and More

Encryption is a method of converting plain text into incomprehensible code known as ciphertext. Its purpose is to conceal sensitive data, preventing unauthorized parties from stealing it.

Usually, sites or web applications use encryption to protect data exchange over the internet. Digital data storage, such as Google Cloud, also uses it to add a security layer.

To help you understand more about data encryption and how it can benefit you, we will explain how it works and its importance. You will also learn about different types of encryption and algorithms.

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Encryption refers to converting plain text data into unreadable code called ciphertext. It works using a key – a mathematically-generated string of text translating the data into code.

Encryption helps hide information, preventing unauthorized parties from stealing it. Furthermore, this security measure can protect both data transmission and storage.

How Does Encryption Work

Encryption uses a cryptographic key – a string of text that scrambles readable data into ciphertext. The sender uses a key to encrypt data, while the receiver uses it for decryption.

Encryption strength depends on the key’s size or length, measured in bits. In cryptography, size refers to how many times the number two multiplies to yield the possible key combinations.

For instance, a one-bit key’s possible combination is two to the power of one. Since it is one bit, the value is either one or zero – two possible permutations.

Shorter encryption keys have fewer combinations, hence easier to guess and less safe. Although the longer ones are safer, the algorithms also play an important role in their security level.

Anyone with the correct secret key can reveal the encrypted message. To prevent unauthorized parties from using it, apply robust encryption key management practices, such as:

  • Key lifecycle management. A data encryption key is useful for a limited time. To avoid misuse, update your key periodically and permanently delete unused ones.
  • Protected storage. Keep your key in secure storage to prevent cyber criminals from stealing it. Use a hardware security module (HMS) to improve storage safety.
  • Access and usage restriction. Only allow authorized users to manage and use your encryption key. Also, restrict its usage permission to only one purpose.
  • Audit log tracking. Record every change, usage, and creation of your key in an audit log. Doing so helps you track the key’s activity history in case of unauthorized use.
An HTTPS website's secure connection indicator in a browser

A great example of a technology using an encryption key is a Secure Socket Layer (SSL) certificate. It enables the HTTPS connection – a secure data transmission between a browser and a website’s server.

Types of SSL

Different types of SSL provide the same level of encryption security. Their differences lie in the number of domains they can protect and the validation level.

Different data encryption solutions may use one or multiple secret keys. While the encryption process may differ depending on them, the overall concept is similar.

Why Is Encryption Important

Encryption is one of the most effective ways to increase data security. In addition to protecting sensitive data, encryption verifies its origin and prevents unauthorized modification.

Aside from data security, encryption improves privacy. It is crucial since people can see your unencrypted data during transmission.

While they may not have malicious intent, revealing sensitive information like confidential company data can have serious consequences.

For site owners, encryption is also important to adhere to digital data protection laws, such as the Payment Card Industry Data Security Standard (PCI-DSS).

Installing SSL on your website is the easiest way to obey these rules. There are many free SSL certificates available, offering robust security features.

Comparison between HTTP and HTTPS security

Important! SSL certificates have an expiration date. To ensure your certificate works properly, regularly conduct a website security audit.

Aside from encrypting data, there are various SSL benefits to your site. For example, it helps improve user experience since browsers warn visitors of a non-HTTPS page.

Types Of Encryption

Based on the number of encryption keys used, there are two data encryption methods – symmetric and asymmetric.

Symmetric Encryption

In symmetric encryption, the sender and receiver use an identical symmetric key to encrypt and decrypt data. Here’s how it works:

  1. The sender and receiver share the same secret key.
  2. Using the secret symmetric key, the sender encrypts the data, turning it into ciphertext.
  3. They send encrypted data through the internet.
  4. The recipient retrieves the encrypted data and decrypts it with the same key, revealing the information.

Since there is only one key, the symmetric encryption process is faster. While still effective, it isn’t as secure as asymmetric data encryption.

Symmetric key encryption is ideal if you prioritize speed over the additional security layer. Companies typically use it for protecting data at rest, such as employment agreement files in one location, like cloud storage.

Asymmetric Encryption

Also known as public key encryption, the asymmetric method utilizes two different but mathematically related keys called public and private.

The public key deals with encrypting data and is available to everyone. Data encrypted with it only unlocks using the corresponding private key.

Meanwhile, only the rightful parties can generate and use the private key. So although everyone can encrypt sensitive data, only the intended recipient can reveal it.

Here’s how the two keys work in asymmetric encryption systems:

  1. Both the sender and receiver generate their asymmetric key pairs.
  2. They send each other the public key.
  3. With the receiver’s public key, the sender encrypts the data and sends it to the recipient.
  4. The receiver decrypts the secured data with their private key.
  5. If the receiver wants to send the data back, they encrypt it using the sender’s public key. Then, the process repeats.

Some technologies use a hybrid approach, combining symmetric and asymmetric methods to encrypt data. SSL or Transport Layer Security (TLS) is an example of such technology.

This hybrid approach uses asymmetric data encryption to secure the symmetric key. Both parties will use it to encrypt sensitive information instead of the public or private key.

Asymmetric encryption offers an additional layer of security but is slower due to the extra steps. It commonly protects sensitive data exchange over the internet, like email messaging.

Encryption Algorithms

An encryption algorithm is a mathematical formula that systematically converts data into ciphertext. It also allows the encrypted data to be reverted into readable plain text.

There are different algorithms for symmetric and asymmetric data encryption. In this section, we will explain six of the most common ones.

DES Encryption

Data Encryption Standard (DES) is one of the earliest algorithms from IBM. This symmetric-key algorithm was the federal encryption standard up until 1999.

Due to security concerns, modern encryption algorithms have replaced the outdated Data Encryption Standard. Its 56-bit key is too short and easy to crack with a modern computer.

Before its depreciation, DES was commonly used to secure electronic financial transactions. Its use cases today include cryptography training and research purposes.

3DES Encryption

3DES (Triple Data Encryption Standard) is the successor of the original DES algorithm. Its purpose was to address DES’ main weakness, namely the short 56-bit encryption key.

Like its predecessor, 3DES is a symmetric data encryption algorithm with a 64-bit block size. It is also designed based on the same Feistel cipher structure.

3DES uses the triple encryption method, applying the DES algorithm for each data block three times. It makes the 3DES key longer and significantly more difficult to decipher.

AES Encryption

The Advanced Encryption Standard (AES) is a more recent symmetric algorithm. It replaced DES as the encryption standard per the National Institute of Standards and Technology (NIST) approval.

The main advantage of AES over DES is its larger key lengths of up to 256-bit key size, making it harder to crack. In addition, the AES algorithm is faster as it is more mathematically efficient.

Among symmetric encryption algorithms, AES is currently the most popular one. Its common use cases include data storage, mobile apps, and Wi-Fi security.

RSA Encryption

Rivest-Shamir-Adleman (RSA) is one of the earliest public key encryption algorithms. Despite being old, it remains popular given its high level of security.

RSA uses the Prime Factorization mathematical method to generate a large string of numbers from smaller combinations. Cyber attackers must determine the small prime number strings from the larger ones to decipher the key.

RSA uses far larger key sizes compared to other asymmetric encryption algorithms. It supports up to 4096-bit keys, which are nearly impossible to solve even with a modern computer.

This algorithm is commonly used to secure web applications, email messaging, and cryptocurrency blockchains. SSL/TLS certificates also use the RSA algorithm for asymmetric encryption.

Twofish Encryption

Twofish is a symmetric encryption algorithm supporting up to the 256-bit key length. It was intended to replace DES but fell short of the secure AES algorithm on 128-bit key performance.

Although slower, this algorithm offers a similar level of security to AES. The main advantage of Twofish is its flexibility which makes it suitable for a wide range of applications.

It allows for performance tradeoffs based on various parameters’ importance, like encryption speed and hardware capabilities. This makes Twofish ideal for applications with limited RAM or storage.

While Twofish is not as popular as AES, some applications use this algorithm:

  • PGP (Pretty Good Privacy) – an encryption program for authenticating, encrypting, and decrypting emails.
  • KeePass – a password manager tool for storage and encryption.
  • TrueCrypt – freeware disk encryption software for securing data.
  • Peazip – an open-source archive file creator and extractor.

RC4 Encryption

Rivest Cipher (RC4) is a symmetric encryption algorithm using a stream cipher system. It is an encryption method that processes the data one byte at a time.

This symmetric encryption is known for its simplicity and performance. Its common use cases include SSL/TLS, Wi-Fi encryption protocols, and web browsers like Microsoft Edge.

However, RC4 is not widely used anymore due to its low level of security. While it supports 2048-bit keys, many studies found that RC4 has significant security vulnerabilities.

There are several RC4 variants developed to address its weakness, namely Spritz, RC4A, RC4A+, and Variably Modified Permutation Composition (VMPC).

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Encryption is a process of scrambling data into unreadable code called ciphertext. Its purpose is to conceal the data until the intended recipient receives it.

Data encryption requires a string of text to convert plain text into ciphertext called a key. This key systematically alters the data, allowing it to be decrypted back into readable plain text.

There are two types of encryption – asymmetric and symmetric. Asymmetric encryption uses two separate keys to encrypt and decrypt the data, while symmetric uses an identical one for both processes.

An encryption’s security strength depends on its algorithm and the key’s length. The longer the key and the more complicated the algorithm, the harder it is to decipher.

Enabling encryption like SSL/TLS improves web applications’ data security and privacy and helps protect your WordPress website. In addition, it is to comply with various data protection laws, such as the PCI-DSS.

Tokenization is a method of substituting sensitive data with other values, known as a token. Unlike ciphertext, a token doesn’t have mathematical relation with the original data, hence irreversible.

The relationship between the data and the token is stored in a database called a vault. Upon receiving requests, the vault will provide the data based on the queried token.

To help you understand more about encryption, we will answer some common questions about it.

What Is a Key in Cryptography?

In cryptography, a key is a string of characters used to scramble data systematically. It is designed based on a certain algorithm to keep the key unique and difficult to guess.

The receiver can only decrypt ciphertext into plain text with the right key. Longer keys have more possible permutations, hence are harder to guess and have higher security. 

What Is Encryption Brute Force Attack?

A brute force attack is when cyber criminals attempt to guess the encryption key. Since there may be billions of possible key permutations, this attack typically involves a powerful computer.

Most modern encryption methods are immune to such an attack, given their long and complex keys. However, some older algorithms like RC4 may be vulnerable despite having long keys.

What Is a Difference Between Encryption and Tokenization?

Tokenization replaces sensitive data with non-sensitive tokens, without a mathematical link, making it irreversible, unlike encryption which maintains such a relationship and allows data retrieval through decryption.

Which Encryption Is the Most Secure?

Many regard Advanced Encryption Standard (AES) as the most secure algorithm for symmetric encryption. Large companies like Google use it to protect data at rest.

For the asymmetric algorithm, Rivest Shamir Adleman (RSA) is the most secure option. It is virtually uncrackable and used for internet applications like browsers and virtual private networks (VPNs).

The author

Aris Sentika

Aris is a Content Writer specializing in Linux and WordPress development. He has a passion for networking, front-end web development, and server administration. By combining his IT and writing experience, Aris creates content that helps people easily understand complex technical topics to start their online journey. Follow him on LinkedIn.