Keys are often used to protect data. The security of data is dependent on the security of its corresponding keys. You can use key versions and the periodic rotation mechanism to improve key security and implement security policies and best practices for data protection.
- Reduce the amount of data encrypted by each key
The security of a key is inversely proportional to the amount of data encrypted by it. This amount is usually defined by the total bytes of data or the total number of messages that are encrypted by the same key. For example, National Institute of Standards and Technology (NIST) defines the secure lifecycle of a key in GCM mode as the total number of messages encrypted based on the key. The periodic key rotation mechanism enables each key to remain secure and minimize vulnerability to cryptanalytic attacks.
- Respond in advance to security events
In the early days of system design, key rotation was introduced as a routine O&M method. This provides the system with a method to handle security events when they occur, and complies with the fail early, fail often principle of software engineering. If key rotation is not executed until an emergency event has already occurred, the probability of system failure increases exponentially.
- Provide logical isolation of data
Encrypted data is isolated with each key rotation from other data encrypted using different keys. The impact of key-related security events can be identified quickly and preventive measures can be taken.
- Reduce the window of time to crack keys
Periodic rotation of encryption keys ensures that you can control and reduce the window of time for which the key and its encrypted data are vulnerable to being cracked. Attackers only have a limited period of time between rotation tasks during which they are able to crack the key. This practice greatly increases the security of your data against cryptanalytic attacks.
- Payment Card Industry Data Security Standard (PCI DSS)
- Cryptography-related industrial standards issued by State Cryptography Administration, such as GM/T 0051-2016
- Cryptography-related standards issued by NIST, such as NIST Publication 800-38D