**The Advanced Encryption Standard (AES) is a very secure symmetric encryption method. It works with block ciphers and is the successor of the Data Encryption Standard (DES). Worldwide, AES is used in many different areas.**

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## What is AES (Advanced Encryption Standard)?

The abbreviation AES stands for Advanced Encryption Standard and denotes an algorithm for symmetric block encryption. The Advanced Encryption Standard is the successor of the Data Encryption Standard (DES) and is used in many areas worldwide. An alternative name for the Advanced Encryption Standard is the Rijndael algorithm. It is derived from the names of the developers Joan Daemen and Vincent Rijmen.

One of the main reasons for the replacement of DES in the 1990s was its short key length of only 56 bits. This meant that DES was no longer sufficiently protected against brute force attacks by powerful computers. With AES, the keys for encryption and decryption are the same. Possible key lengths are 128, 192, or 256 bits. The three designations AES-128, AES-192, and AES-256 are derived from the key length.

In the USA, AES is standardized by NIST (National Institute of Standards and Technology). The algorithm is not patented and is freely available. It can be used without license fees and is implemented in numerous hardware and software.

So far, no practically relevant attack methods have been found on the encryption method. It is, therefore, suitable for the encryption of sensitive documents and is used, among other things, for U.S. government documents with the highest classification level.

## Using the AES encryption method

Encryption by Advanced Encryption Standard has found its way into many areas and applications. Among others, the algorithm is used for:

- Wireless LAN according to IEEE 802.11i
- WiMAX according to IEEE 802.11m
- VPNs with IPSec
- Secure Shell (SSH)
- VoIP telephony
- Encryption of files
- Encryption of disk archives
- RAR, 7-Zip, PGP, GnuPGP
- OpenSSL

The Advanced Encryption Standard is also integrated into many operating systems, such as macOS, and fulfills various tasks. Numerous processors from Intel and AMD, as well as processors for mobile devices, support AES in hardware and thus achieve high encryption and decryption performance.

## Security aspects of the Advanced Encryption Standard

While there are some theoretical considerations of possible weaknesses in the Advanced Encryption Standard, to date there is no known practical way to compromise the algorithm. Brute force attacks with today’s available computer power are not able to find the key in sufficient time due to the key lengths.

However, due to the rapid advancement of technical development and increasingly powerful computers, it can be assumed that brute force attacks could possibly be successful in the future. However, the current security buffer is still very large when 256-bit keys are used, making AES a secure encryption method for many years to come.

It cannot be ruled out that a solution to the mathematical equation of the algorithm may be found in the future. If this were the case, keys would be directly computable and encryption with the Advanced Encryption Standard would no longer be usable. Currently, no mathematical method is known that would be able to solve a task with such great complexity.