What is AES encryption and how does it work? | CDVI UK (2024)

“AES256 is virtually impenetrable using brute-force methods. While a 56-bit DES key can be cracked in less than a day, AES would take billions of years to break using current computing technology. Hackers would be foolish to even attempt this type of attack.”

– N-ABLE

AES is asymmetricencryption method, meaning it uses the same key to encrypt data as it does to decrypt data.

It also applies multiple rounds of the SPN (substitution permutation network) algorithm to encrypt data. The sheer number of encryption rounds that AES utilises are what makes it so impenetrable.

There are three possible lengths of AES keys. Each key length offers a different number of possible key combinations. The higher the bit-rate of the AES encryption, the more possibilities there are, and the higher the security.

• 128-bit key length: 3.4 x 10³⁸
• 192-bit key length: 6.2 x 10⁵⁷
• 256-bit key length: 1.1 x 10⁷⁷

Even though the key length of this encryption method varies, its block size remains the same at 128 bits.Block sizerefers to the way the data being encrypted is split up and organised. Data is arranged into a 4×4 array of 16 bytes. There are8 bits in every byte, so each block contains128 bitsin total.

The AES algorithm is a complex mathematical concept, which the majority of people would struggle to understand. Fortunately, in the security industry it’s more important for us to understand what makes AES so robust and how it can be applied.

This is a basic overview of how AES works, from theCloud Boffins website:

Simply put, AES takes a block ofplain textand applies alternating rounds of substitution and permutation boxes to the passage. This form of encryption is known as a substitution permutation network (SPN) block cipher algorithm, and the size of the boxes alternate between 128, 192 or 256 bits, depending on the strength of encryption. The standard strength for encryption is 128, with 256 reserved for as and when the strongest levels of protection are required.

During this substitution-permutation process, anencryption keyis generated, which can then be used to decipher and read the protected information as was originally intended. Without this decryption key, the data is completelyillegibleand totally scrambled, meaning it’s useless to third parties who intercept traffic in the hope of stumbling on data they can steal.

Algorithms for use with AES have to be designed, analysed, and approved for use. They are judged by the international cryptographic community for a number of criteria.

Securityis the most important factor for a proposed algorithm. It must be able to successfully resist attack.Costmust also be considered, as computational power and memory efficiency can vary, affecting cost. The overallflexibilityandease of useis also taken into account.

Advantages of AES encryption

The primary advantage of AES is its robust security. Beyond that, the encryption process is relatively simple and can be implemented relatively easily.

AES encrypts and decryptsquickly, making it a practical security solution. In addition, AES is a morecost-effectiveand environmentally-friendly encryption method as it requires less memory than other methods.

AES is also flexible enough to be combined with a variety of other security protocols like WPA2 or SSL. It can therefore function as an extra layer of security when additional protection is needed.

After being adopted by the US government as its preferred encryption cypher, AES became theglobal standard. It is used widely for all kinds of online activity, in practically every industry on the planet.

When you enter your passwords and PINs for online banking, you are using AES encryption. Many popular apps such as Facebook and Snapchat use it too. Have you ever compressed a file using WinZip or RAR? That’s AES encryption.

How CDVI uses AES encryption:

• KRYPTO Encrypted Access Control

The KRYPTO system utilises AES encryption to protect the transfer of data between the different components of the system. Between the ATRIUM web server and the controller, the controller and the reader, and the reader and the credential, data is secure. This is an ideal solution for high security environments like banks and official facilities.

• RX128-XPL Receiver and TX128-E Transmitters

The RX128 and TX128 series utilise AES128 encryption to secure the signal passed between the receiver and the transmitters. It allows wireless access control systems to combine both the flexibility of radio transmission with the security of AES encryption.