Advantages of AES | disadvantages of AES

This page covers advantages and disadvantages of AES. It mentions AES advantages or benefits and AES disadvantages or drawbacks. It also describes AES basics.

What is AES?

Introduction:
• AES is the short form of Advanced Encryption Standard.
• It is FIPS approved cryptographic algorithm used to protect electronic data.
• It is symmetric block cipher which can encrypt and decrypt information.
• Encryption part converts data into cipher text form while decryption part converts cipher text into text form of data.
• AES algorithm used different keys 128/192/256 bits in order to encrypt and decrypt data in blocks of 128 bits.
• AES is implemented in both hardware and software to protect digital information in various forms data, voice, video etc. from attacks or eavesdropping.

The figure-1 depicts two modes of AES algorithm viz. CTR (counter) mode and OFB (Output Feed Back) mode.

In CTR (counter) mode, the output of the Counter is the input for the Encryption core and an initialization vector is used to initialize the counter. Input data is encrypted by XOR'ing it with the output of the Encryption module. The data coming out after this operation is called cyphertext. Decryption reverses the encryption operation.

In OFB mode, the output of the Encryption operation is fed back to the input of the Encryption Core. An initialization vector is used for the first iteration. Input data is Encrypted by XOR'ing it with the output of the Encryption module.

AES type	Key Length (Nk words)	Block Size (Nb words)	Number of rounds (Nr)
AES-128	4	4	10
AES-192	6	4	12
AES-256	8	4	14

The table above mentions three types of AES based on key lengths used in the algorithm.
Also refer AES Basics and MATLAB Code >>.

Benefits or advantages of AES

Following are the benefits or advantages of AES:
➨As it is implemented in both hardware and software, it is most robust security protocol.
➨It uses higher length key sizes such as 128, 192 and 256 bits for encryption. Hence it makes AES algorithm more robust against hacking.
➨It is most common security protocol used for wide variety of applications such as wireless communication, financial transactions, e-business, encrypted data storage etc.
➨It is one of the most widely used commercial and open source solutions across the world.
➨No one can hack your personal information.
➨For 128 bit, about 2¹²⁸ attempts are needed to break. This makes it very difficult to hack it as a result it is very safe protocol.

Drawbacks or disadvantages of AES

Following are the disadvantages of AES:
➨It uses too simple algebraic structure.
➨Every block is always encrypted in the same way.
➨Hard to implement with software.
➨AES in counter mode is complex to implement in software taking both performance and security into considerations.