crc-5

Comments-1 100 Words. Introduction

            Advanced Encryption standard relies on some basic parameters for better performance. These parameters include key size that refers to words, bytes or bits ranging from four to 256; block size of plaintext, frequency of Rounds, key size of Rounds and increased size of the key (Compastié et. al., 2020).

AES Structure and Benefit

            AES starts with processing of the concerned block of data into a unified entity while performing substitutions and permutation throughout the rounds. Expansion of input key is followed after this. Substitute bytes, ShiftRows, MixColumns and AddRounddKey are the four crucial stages in the standard. The first stage that is Substitute byte makes use of S-box system in order to develop a substitution of the block having byte-by-byte consideration. The next stage ShiftRows is a permutation in its simplest form. MixColumns is another substitution which is based on the application of arithmetic on GF (Ibrahim, 2019). AddRoundKey exists in a portion of the expanded key and happens to be an XOR with simple bitwise  key. The AES structure repeats its encryption and decryption in each round that has all these four stages starting from AddRoundKey. This is the stage where the cipher begins. Thus, this stage is considered as the main stage for security. However, all the stages can be reversed without hassle. Decryption in this standard depends on the use of expanded key in the opposite direction (Compastié et. al., 2020). The structure itself reveals the benefits of AES that include larger key size for better security and performance, fast implementation for hardware and software invariably, convenient block size to prevent attacks and last but not the least – it is the most accepted standard for encryption in most countries.

Conclusion

            However, benefit of one system is better determined when it is compared to the other systems of same field. Hence, AES is belived to be better performing than DES or 3DES. Firewalls and routers requiring low latency and high throughput get better security and speed through AES.

 

References

Compastié, M., Badonnel, R., Festor, O., & He, R. (2020). From virtualization security issues to cloud protection opportunities: An in-depth analysis of system virtualization models. Computers & Security, 97, 101905. doi: 10.1016/j.cose.2020.101905

Ibrahim Turki, A., Hasan Zwiad, A., & M. Almuttairi, R. (2019). Security Issues, Attacks and Vulnerabilities for Virtualization in Cloud Computing and their Solutions. Journal Of Engineering And Applied Sciences, 14(6), 9509-9518. doi: 10.36478/jeasci.2019.9509.9518

Comments-2 100 Words. To protect classified information, the United States government selected advanced encryption standards (AES). This standard has been adopted globally, with a significant focus on the protection of sensitive data. The AES structure is unique, hence presenting more advanced protection, challenging to counter any attempts to breach the laid down procedures.  The AES processes the whole block as a single matrix in each round based on substitutions and permutation. The key that is provided within the system is expanded into an array of forty-four 32-bit words. The main stages used are mainly four, which offer greater security to the underlying data being protected.  

The four significant stages utilized include substitute bytes, which employs S-box to conduct byte operation through the block's substitution.  Shift rows utilize permutation. Max Columns is a substitution that employs arithmetic over GF while Add Round Key is a simple bitwise XOR of the existing block with a portion of the expanded key.  The AES structure creates a strong link that is difficult to overcome, hence being preferred in handling classified information by governments and security agencies globally.

The cipher starts and ends with an Add Round Key stage. Each stage within the structure is reversible, allowing overall focus on different processes that can be considered to advance structure development. The description algorithm developed uses the expanded key in reverse order, although it is not identical to the encryption algorithm developed. A significant risk to the AES encryption comes from the side-channel attacks, although AES's layered nature makes it difficult to penetrate the system. There are ten rounds of 128-bit keys, 12 rounds for 192-bit keys, and 14 rounds for 256-bit keys. These rounds have several processing steps that include substitution, transposition, and mix of plaintext and ciphertext.

 

 

References

Kahate, A. (2013). Cryptography and network security. Tata McGraw-Hill Education.

Stallings, W., & Tahiliani, M. P. (2014). Cryptography and network security: principles and practice, vol. 6.