What is Advanced Encryption Standard (AES)?

What is AES?

The Advanced Encryption Standard (AES) is a symmetric encryption algorithm that secures data using a shared key. It’s fast, reliable, and widely adopted—making it one of the most trusted methods for protecting sensitive information.

Originally introduced by the National Institute of Standards and Technology (NIST) in 2001, AES replaced the older DES algorithm. It’s based on the Rijndael cipher and supports 128-, 192-, and 256-bit key lengths, providing flexibility and security across a range of use cases.

Whether you’re encrypting data in motion or at rest, AES is built for performance without compromising protection.

Why AES is essential for identity and access security

Encryption is a pillar of modern cybersecurity—and AES plays a central role in protecting access. It’s not just about hiding data. It’s about building trust in the systems that store and move that data.

When AES is used correctly, it helps organizations:

• Protect sensitive credentials—from privileged account passwords to authentication tokens
• Secure access to critical systems through VPNs, encrypted databases, and disk-level protections, or SaaS solutions like Privileged Remote Access. 
• Comply with regulations like HIPAA, PCI-DSS, and GDPR by demonstrating responsible data handling 
• Support Zero Trust strategies by safeguarding communications between verified users, apps, and endpoints

AES isn’t a bolt-on—it’s a building block in a secure-by-design approach.

How AES works

AES encrypts data in blocks of 128 bits using a process called substitution-permutation. It uses multiple rounds of transformation to scramble data—each round applying a unique operation based on the encryption key.

In simplified terms: 

• Input data is broken into 128-bit chunks
• The system applies a series of transformations, including byte substitution, row and column shifting, and mixing
• A unique key is added at each stage
• The output is unreadable ciphertext—until it’s decrypted with the matching key

AES is symmetric, so the same key is used to encrypt and decrypt the data. That makes key management critical to security.

Where AES shows up in real environments

AES powers encryption behind the scenes in tools and services you use every day: 

• Wi-Fi (WPA2, WPA3)
• Secure file storage and full-disk encryption 
• VPN tunnels and TLS connections
• Authentication workflows in password managers and cloud apps

Example: A healthcare provider uses AES-256 to encrypt patient records stored in a cloud-based system. Paired with access controls and MFA, the data stays protected from unauthorized access—supporting HIPAA compliance without slowing down care delivery.

Getting encryption right

AES is strong, but implementation matters. Missteps like weak key storage, using insecure modes like ECB, or failing to rotate keys can leave data vulnerable.

To get it right:

• Use AES-256 for highly sensitive data
• Choose secure modes like GCM or CBC with strong initialization vectors
• Combine with identity-based access controls for layered protection 
• Regularly review and update encryption practices and key management policies

Built to last

AES has stood the test of time. It’s fast enough for modern applications, strong enough to meet evolving compliance needs, and flexible enough to support enterprise-scale operations.

As organizations grow and threats evolve, encryption shouldn’t be an afterthought. It should be a given—embedded in every layer of access and identity protection.

Start by reviewing where and how AES is used in your environment. Then take steps to strengthen how it’s deployed—because even the best encryption is only as strong as the controls around it.

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