What Is Advanced Encryption Standard (AES), and How Is it Related to NIST?

Our digital age is rooted in the exchange of data, and therefore security of that data. Obfuscation, or encryption, has served as the backbone of that security for decades. As threats have evolved and attackers have found new and more sophisticated ways to break encryptions, it has been up to experts to provide solutions. In the year 2000, the solution was the Advanced Encryption Standard, or AES, which replaced aging encryption methods.

How Does AES Encryption Work?

AES is a symmetric encryption algorithm, meaning that it uses the same cryptographic key for data encryption and decryption. Furthermore, it is known as a “block cipher” in that it runs transformations on data blocks. 

• Symmetric Encryption: Using the same key for both encryption and decryption increases the speed and complexity possible from the algorithm–a massive plus for encryption. It also means, however, that there are additional security measures to put into place to protect those keys because they can never be made public. 
• Block Cipher Encryption: AES operates on blocks of data with a fixed size of 128 bits, and it employs a variable key length of 128 bits, 192 bits, or 256 bits, depending on the specific variant being used. The larger key sizes provide higher levels of security.

Additionally, the AES encryption process involves several transformations, including substitution, permutation, and mixing operations, to scramble the data securely. Decryption follows this process but in reverse order.

The AES algorithm is known for its strong security and efficiency. It is suitable for various applications, including data encryption in multiple industries, secure network communication, and protection of sensitive data stored on devices.

Where Was AES Developed?

The National Institute of Standards and Technology (NIST) created AES to replace the outdated and vulnerable Data Encryption Standard (DES). Previously, DES was the standard used by NISt, and therefore the government, to protect sensitive data. And, this made sense– it was developed in the early 1970s by IBM, and it served as the standard encryption algorithm for the U.S. government and many other organizations throughout the 1970s and 1980s.

Over time, as computing power increased, it became evident that DES’s relatively small key size(64-bit keys with 56 usable bits) made it susceptible to brute-force attacks where an attacker could essentially guess the key with repeated guessing. The demand, therefore, was more complex encryption that was irreversible and produced keys that were practically impossible to crack.

In response, NIST initiated a process to select a new encryption standard that would provide a higher level of security while remaining efficient and practical for widespread adoption. NIST issued a public call for cryptographic algorithms in 1997 and received numerous submissions.

After an extensive and transparent evaluation process, which included public reviews and analysis by experts worldwide, NIST selected the Rijndael algorithm, proposed by Belgian cryptographers Joan Daemen and Vincent Rijmen, in October 2000.

The Rijndael algorithm was found to be solid in the face of these attacks. It worked on 128-bit blogs of data and utilized either 128, 192, or 256-bit keys. 

Today, the standard is published by NIST as an acceptable encryption standard for use in other frameworks and regulations and has found its way into several different applications.

Where Is AES Encryption Used?

By creating AES, NIST ensured that organizations and individuals could employ a robust and well-vetted encryption standard to protect their data, communications, and sensitive information from potential adversaries and cyber threats.

AES is widely used for encryption in various applications and industries due to its strong security, efficiency, and versatility. Some common applications of AES encryption include:

• File, Database, and Standalone Encryption: AES is most often used to encrypt data at rest. This includes information stored in servers, databases, hard drives, or other removable data that will store data for short or long-term purposes.
• Asymmetric Encryption: There are several asymmetric (or public key) protocols that will use AES as part of their process. For example, AES might be used as a way to encrypt data, with the key information obfuscated with a second layer of public encryption. Otherwise, AES is rarely used on its own as a method of encrypting data in transit.
  
• Financial Transactions: As part of both at-rest and in-transit encryption algorithms, AES helps secure financial data and transactions for the growing world of online banking and eCommerce.
  
• Virtualization: AES encrypts virtual machines and data in virtual environments, enhancing the security of virtualized systems, including Virtual Private Networks (VPNs), virtual mobile networks, and virtual machines.
• Protecting Government Data: AES is often considered a minimum requirement for any service provider or contractor working with the U.S. government, with AES-256 being a strong, nigh-unbreakable version. 

What Are the Benefits of AES Encryption

Strong encryption is generally considered a good thing, and having something like AES would fit that purpose. Not all technology is created perfectly, but AES is not different–it has several benefits and drawbacks.

Some of the primary benefits of AES security include:

• Robust Security: AES is provably strong and, in terms of contemporary technology, nigh unbreakable. The current instantiation of AES-256, for example, would take millions of years to brute-force. This doesn’t protect against social engineering attacks, nor does it take into account emerging quantum computing technologies.
• Versatility: AES supports multiple key sizes (128, 192, and 256 bits), making it adaptable to security requirements and use cases.
  
• Efficiency: AES, like many symmetric key systems, is a computationally efficient encryption algorithm, enabling fast encryption and decryption processes even on resource-constrained devices like smartphones or IoT devices.
  
• Publicly Available: AES is a public standard published and maintained by NIST. This means that the algorithm’s details are openly available for review and scrutiny by security experts worldwide. This transparency helps identify and fix potential vulnerabilities.

That all being said, some costs come with AES encryption. These include:

• Key Management: Proper key management is crucial for securing AES-encrypted data. The complexity of managing and securely storing encryption keys can be a challenge, especially for large-scale deployments.
  
• Key Length Trade-Offs: Longer key sizes (e.g., AES-256) provide higher security but require more computational resources than shorter key sizes (e.g., AES-128). Organizations need to find a balance between security and performance.
  
• Compatibility with Legacy Systems: In some cases, older systems or devices may not support AES encryption, requiring additional efforts for migration or maintaining backward compatibility.

Track Encryption and Security in Your Compliant Systems with Lazarus Alliance

Encryption is a critical component of any regulatory and security framework–so obviously, it cannot be ignored. More importantly, your organization must implement the right kind of encryption at the right place, with suitable complexity. 

When you work with Lazarus Alliance, you work with a group of experts that will ensure that your encryption standards are up to spec and applied where they need to be to keep your systems compliant and secure. 

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