What is AES 256-bit Encryption? (and how it protects you)

What is AES 256-bit Encryption?

There is a heightened need for online security at the moment. Cybercriminals are evolving better strategies for stealing data from unsuspecting, unsecured users. One way to prevent this is by encrypting your network. Different encryption systems exist, but the AES 256-bit is the most popular, and perhaps the most secure.

In this article, you will find all you need to know about it.

What Does AES 256-bit Encryption Mean?

First, we will have to start by defining what encryption means. When you encrypt data, you take its raw form, known as plaintext, and perform an algorithmic function on it. This turns it into an encrypted ciphertext. The algorithm used in encrypting data is known as the key. Typically, the key used for every encryption is a closely guarded secret. The only exception is public keys used in asymmetric encryption.

Basically, there are two types of encryption. One of them has been mentioned above, i.e., asymmetric encryption. The other is, as you can guess, symmetric encryption.

Symmetric encryption is also known as private key encryption. This is because the parties on both ends must share the same key used during the encryption and decryption.

Asymmetric encryption is sometimes referred to as public key encryption. You may also want to imagine it as one-way styled encryption. In this scenario, both parties need not share the same private key. The party on one end has the public encryption key, and the other has a private encryption key.

256-bit encryption refers to an encryption technique where a party uses the 256-bit key to encrypt and decrypt files. It is one of the most secure encryption systems world over. Other options include the 128-bit and the 192-bit. They are, however, not as secure. These bit key sizes are used in modern security algorithms such as AES and SSL.

AES stands for Advanced Encryption Standard. The AES is a cipher algorithm that secures your online activities.

Why Was the AES 256-bit Encryption Developed?

The United States’ government developed the AES 256-bit to serve its needs. Before its creation, federal agencies in the US made use of a 56-bit symmetric-key cipher design. This was known as the Data Encryption Standard (DES) and was the creation of IBM. This was around the 1970s, and this encryption cipher held sway for close to 30 years.

However, with the passage of years, it became evident that DES could get compromised easily. In fact, the Electronic Frontier Foundation once demonstrated that it took time no more than 22 hours to break a DES key. The government then decided that it was imperative to find a better encryption standard.

The United States government threw the competition open, asking interested parties to design an alternative system. As expected, several entries came in and were eventually narrowed down to just five finalists, and finally to a winner. The winner comprised two Belgian cryptographers known as Vincent Rijmen and Joan Daemen. The symmetric-key block cipher they developed was similar to the DES, except that it was more sophisticated. Eventually, this new system was named after these two cryptographers. The name, Rijndael, was crafted using a combination of their two names. In 2002, it was renamed the Advanced Encryption Standard.

Since that time, the United States’ National Security Agency (NSA) has approved the AES algorithm for securing its data. This piqued the interest of the rest of the technology community. It also improved its popularity, to the extent that AES libraries have been developed for most programming languages.

The AES algorithm has an open nature. Both public and private parties, commercial and noncommercial entities, can utilize the AES encryption.

How Does the AES 256-bit Encryption Secure Data?

AES makes use of symmetric encryption. As explained earlier, this means that both the sender and receiver should have access to the same keys.

Also, AES is also called a block cipher. This is because the data that is to be encrypted is first divided into blocks.

AES works much in the same manner that general encryption works, too. Here, new units of data are created and subsequently used to replace a former one. The determiner of which one is used is the security key. However, AES is different from other encryption processes because it makes use of the substitution-permutation network. Thus, AES makes use of a key expansion process.

The initial key creates a bunch of subsequent new keys known as round keys. The round keys are not created just from one round of modification; the process repeats itself several times, making it more difficult for a hacker to break through.

The first step in the process is the addition of the initial key to the block. An XOR cipher is typically used for this part of the process. Afterward, each byte of data gets a substitution. There is a predetermined table, which makes the process a lot easier. Next comes the shifting – bytes in the rows of tables are shifted on to the next. Furthermore, the rows are mixed. At the mixing stage, the bytes are all combined into one column. In the end, the round key is then added to the block to complete the process.

The AES encryption algorithm is quite complicated and makes sure that no part of the process gets skipped. This is because each stage serves a crucial function in determining security. For instance, byte substitution is responsible for obfuscating the data used in the process. It also makes sure that the encrypted data cannot be traced back to the original data.

Shifting the rows and columns is also quite strategic. This is because it diffuses the data, further complicating the encryption. Mixing achieves this same effect, too, the difference being that it works vertically while shifting works horizontally. The result? A deeply complicated, almost impenetrable encryption.


In this article, we tried to keep everything as simple as possible, so you can follow the discussion. In summary, just bear in mind that you cannot do without some form of security, given the porous nature of today’s internet. Encrypting your data is your best bet against any attacks. Furthermore, encryption using the AES 256-bit offers you impenetrable security.