Locking the Blocks: EBS Encryption Explained

What is EBS Encryption?

Amazon EBS Encryption helps protect your data at rest, in transit, and in snapshots by automatically encrypting all data written to an EBS volume.

It uses AWS Key Management Service (KMS) for key handling and AES-256 encryption for data security.

With EBS encryption:

Data stored on the volume is encrypted.
Data moving between the instance and the volume is encrypted.
Snapshots and volumes created from encrypted data remain encrypted.

How EBS Encryption Works

When you enable encryption on an EBS volume:

AWS automatically uses your KMS key (Customer Master Key - CMK).
The data, snapshot, and all copies created from the volume are encrypted.
Encryption and decryption occur transparently — no performance overhead.

Key Encryption Components

Component	Description
Data Key	Used to encrypt data on the EBS volume. Managed by AWS KMS.
Customer Master Key (CMK)	The main key stored in KMS that encrypts the data key.
AWS KMS	Manages creation, storage, and rotation of keys securely.

Encryption in Action (kaptaindevops Example)

Scenario:

kaptaindevops is running multiple EC2 instances storing sensitive application logs and user data.