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    Encryption 6 min read

    What Is AES Encryption?

    AES encryption is a form of cryptography used to secure some of the world’s most sensitive information. It is approved by the National Institute of Standards and Technology (NIST) as gold standard for data encryption.

    Encryption is an important feature of most security architectures. Simply put, it means converting information into a code, to prevent it from being accessed by an unwanted viewer. It is commonly used by websites, email services, banks and crypto wallets.

    How does AES Encryption work?

    Short for Advanced Encryption Standard, AES is a symmetric 128-bit block data cipher algorithm. It splits the original data into blocks, or chunks, of 128-buts in size, and then uses keys of 128, 192 or 256 to encrypt that data.

    Encryption itself is a process of substitution and permutation: in other words, it substitutes parts of the original text for elements of the output, while also shuffling elements of the data during rounds of processing.

    The final output of this process of substitution and permutation is a cipher text: the ecnrypted version of the original data. AES uses symmetric encryption, which means it uses the same cipher both to encrypt the original data, and also to decrypt it again when it needs to be accessed.

    AES can support key sizes of 128, 192 and 256 bits, each of which offers a different level of complexity to the final cipher text.

    Different types of AES encryption

    There are three levels of AES encryption available today:

    AES-128 encryption

    This iteration uses a key size of 128 bits, and involves ten rounds of processing during encryption and decryption of information.

    AES-192 encryption

    This version employs a key size of 192 bits, and effects 12 rounds of processing during the encryption and decryption process.

    AES-256 encryption

    This version uses a key size of 256 bits and goes through 14 rounds of processing during encryption and decryption of information. With the greatest level of complexity, AES-256 is the most secure version of AES. However, this also means the encryption and decryption process takes significantly longer than less complex versions, meaning it carries an operational trade-off.

    What Are the Benefits of Using AES Encryption?

    AES is considered to be highy secure, and capable of guarding the most sensitive information, such as government data. The principal reasons why it’s regarded as so secure include:

    Significant key size

    With key sizes of 128, 192 and 256 bits, AES offers incredibly complex encryption that is effectively impossible to penetrate via brute force attack. For example, information encrypted using a 256 bit key would take today’s computers an almost infinite amount of time to crack via reverse engineering or random guessing.

    Multiple layers of encryption

    Each version of AES using multiple rounds of processing during the encryption and decryption of information. During each round of processing, raw data and its different permutations are mixed in different ways. So multiple rounds of processing makes it incredibly difficult to reverse engineer encryption to uncover the original information.

    Open source and transparent

    AES is completely open source by design. This is important, because it avoids the possibility of a “back door” in the techology that would allow access to your information. Open source technology of all kinds means end users know exactly what the technology does, with no blind spots and no opportunities for hacks by a malicious developer.

    How was AES developed?

    AES was developed as a replacement for DES (Data Encryption Standard), a standard used by the US government to encrypt state secrets.

    DES used a 56-bit symmetric key cipher design, meaning it broke information into 56 separate bits to be encrypted. But as technology became more powerful, DES could be deciphered by the computers of the day. This meant it was no longer secure enough to conceal highly sensitive information.

    The US government launched a public competition to find a more secure encryption standard. The winning entry was the Rijndael cipher – the original name of AES. It was chosen not only because of security, but also based on computational efficiency: fast ecryption and decryption was essential across a range of devices.

    AES also offered a degree of flexibility, providing different key sizes for uses in different environments.

    Since its adoption in 2001 by the National Institute of Standards and Technology, AES has become the most widely employted symmetric encryption algorithm globally. It is used across various industries, from banking and communications, to governments, military and of course crypto.

    In What Applications Is AES Used?

    Thanks to its efficiency, world-class security and flexibility, AES has many different applications, spanning many industries. These include:

    Virtual private networks (VPN)

    A VPN is an encryption tunnel that enables you to access the internet while your activity remains private. This privacy is garanteed by AES encryption.

    Using AES, your VPN will encrypt all of the traffic passing through its servers, meaning nobody – not even your internet service provider – can see what you’re doing.

    Payment systems

    As we increasingly do business online, digital payment systems and banking platforms need the highest level of data protection. When you enter your payment or banking details on a website, you need to know nobody can see this information – even if your network has been hacked into.

    This is where AES comes in. Online financial platforms encrypt the data entered by you, enabling you to make payments without website hosts or hackers being able to decipher your details.

    Secure communication

    Have you ever wondered why your email or messaging platform can’t see what you’re sending? The answer is AES encryption. Internet protocols like SSL/TLS and HTTPS encrypt the data you’re inputting for websites, emails and messaging apps, making sure nobody but you and the sender can access that information.

    Government and military

    As the approved ecnryption method of the US government, AES is used to conceal the most sensitive state-level and military information.


    Cryptocurrency wallets use AES to remain secure and impenetrable to reverse engineering. AES is also used to secure the crypto transaction process.

    What’s the difference between AES and Rijndael encryption?

    While the terms AES and Rijndael are used interchangeably, there are some differences between the two. AES has a fixed block size of 128-bits and a key size of 128, 192, or 256-bits, whereas Rijndael can be specified with any key and block sizes in a multiple of 32-bits, with a minimum of 128-bits and a maximum of 256-bits.

    When was AES adopted by the US government?

    The U.S government adopted the algorithm as its encryption technique in October 2000, replacing the DES encryption it previously used. The National Institute of Standards and Technology (NIST) of the U.S. Department of Commerce had selected the algorithm, called Rijndael (pronounced Rhine Dahl or Rain Doll), out of a group of five algorithms under consideration, including one called MARS from a large research team at IBM.