Data Encryption with DES Algorithm : Cybersecurity Concepts
A vital cybersecurity skill is understanding data encryption. Data encryption has long been done using the DES algorithm. It makes sense to learn how it works and how it may be applied. In this article, we describe the implementation and functioning of the DES algorithm.
DES Algorithm : Overview
A block cipher algorithm is DES. Using symmetric keys, it converts blocks of 64-bit plaintext into blocks of 48-bit ciphertext. The DES Algorithm was developed in the 1970s by the IBM team.
It has since received approval from the National Institute of Standards and Technology (NSIT). The DES encryption algorithm uses symmetric keys, employing the same key to encrypt and decode data.
Triple DES Algorithm
Triple DES is a block encryption that employs the DES algorithm three times. It frequently uses the three keys k1, k2, and k3. The first key, designated k1, the second key, k2, and the third key, designated k3, which is used to re-encrypt, are all utilised.
There is a triple DES variant that only requires two keys, where k1 and k3 are the same.
Steps in DES Algorithm
Here are the steps that make up the DES algorithm :
- To the initial permutation (IP) function is provided the 64-bit plaintext block.
- The IP is performed using the plaintext.
- The IP then splits the permutated block in two.
- The two components are referred to as the right plain text (RPT) and the left plain text (LPT).
- Each and every LPT and RPT is 16 times encrypted.
- The final permutation is applied to this block when the LPT and RPT are joined (FP).
- The 64-bit ciphertext needs to be created
There are five phases in the encryption procedure (step 4) :
- Key Transformation
- Expansion Permutation
- S-Box Permutation
- P-Box Permutation
- XOR, and Swap
The same process is used for decryption, but with the 16 keys’ order will be inverted.
Modes of Operation for DES
The many DES modes of operation include the ones listed below:
Electronic Codebook (ECB): Each 64-bit block is encrypted and decrypted separately in this block.
Cipher Block Chaining: Each 64-bit block in this method, known as cipher block chaining (CBC), depends on the block preceding it. It uses a vector for initialization (IV).
Cipher Feedback (CFB): In this mode, the previous ciphertext serves as the input for the encryption process. As a result, the output is pseudorandom.
Output Feedback: The plaintext and this output are then XORed. The following ciphertext unit is so produced.
Output Feedback (OFB): This mode is similar to CFB with the exception that the output of the preceding DES serves as the input for the encryption process.
Counter (CTR): Every block of plaintext is XORed with an encrypted counter in the Counter (CTR) mode. The counter will grow with each succeeding block.
Implementation of The DES Algorithm
A security provider is mandatory for the DES algorithm to be employed. Choosing one of the many vendors available on the market must be the first step in the implementation process. The terminology you use will have an impact on the provider you choose. This might be MATLAB, Java, C, or Python.
You must pick how the key will be made after selecting the source. You have the choice of letting the key generator generate it at random or generating your own key.For this, you may use either plaintext or a byte array.It is essential to test the encryption so you can be sure it is being used correctly.
Applications of the DES algorithm
When weak encryption is required, the DES algorithm is utilized. It may be applied to permutation generators or random number generators. The development of triple DES legacy systems with three keys is one of the DES algorithm’s most significant practical uses.
Difference Among DES and AES Algorithms
They are both symmetric ciphers: AES and DES. What distinguishes them from one another, then? Let’s explore
| Factor | AES | DES |
| Description | Advanced Encryption Standard is referred to as AES. | The data encryption standard is known as DES. |
| Key Length | The length of the key might range from 128 bits to 256 bits. | The key is 56 bits long. |
| Operation Rounds | Following are the rounds of operations for each key length: 10 128 bits, 12 192 bits, and 14 256 bits | 16 identical rounds of procedures are performed. |
| Network | A substitution and permutation network are the foundation of AES. | The Feistel network forms the basis of DES. |
| Security | DES is less safe than AES, which is regarded as the industry-standard encryption method. | Triple DES is a more secure encryption method than DES, which is regarded as a poor encryption technique. |
| Rounds | Shift Row, Byte Substitution, Mix Column, and Key Addition. | Expansion, Permutation, XOR Operation, and Substitution. |
| Size | AES can encrypt 128-bit plaintext. | DES can encrypt 64-bit plaintext. |
| Derived Source | The Square Cipher served as the basis for AES. | The Lucifer Cipher served as the basis for DES. |
| Designed By | Vincent Rijmen and Joan Daemen | IBM |
| Known Attack | AES is not subject to any known attacks. | Linear cryptanalysis, differential cryptanalysis, and brute force assaults. |
Advantages and Disadvantages of DES Algorithm
Let’s explore the advantages and disadvantages of the DES Algorithm.
The Benefits of DES Algorithm
The following are some of the advantages of DES Algorithm:
- The algorithm has been in use since 1977. Technically, there are no problems with the algorithm. Brute force attacks continue to be the best ones to use against the DES algorithm.
- The standard was created by the US government as DES. The government must recertify DES every five years and, if required, ask for its replacement.
- The American National Standards Institute (ANSI) and the International Organization for Standardization both acknowledge DES as a standard (ISO). This shows that anyone may access the algorithm and learn how to apply it.
- DES was designed for hardware, but it is only marginally fast in software.
The Limitations of DES Algorithm
The DES algorithm has a number of drawbacks, the worst of which is probably the 56-bit key size. Chips can encrypt and decode a million DES operations in a second. A DES cracking device that can search all the keys in around seven hours costs $1 million.
- Hardware is easily able to implement DES. However, because it was not designed for software, it operates quite slowly on it.
- The DES-encrypted code has grown easier to decipher as technology develops. Today, AES is advised above DES.
- DES uses a single key for both encryption and decryption as a symmetric encryption technique. If that one key is lost, we won’t be able to obtain any decipherable information.
Conclusion
The symmetric block cipher DES can convert 64 bits of plaintext into 64 bits of ciphertext. The same algorithm is used throughout both the encryption and decryption procedures. The only difference is that the decryption method is exactly the opposite of the encryption process. At the end of every 16 rounds, the algorithm gets stronger.
