What security measures protect data on persistent storage?

Data on persistent storage is protected through encryption, access controls, backup systems, and intrusion detection systems.

Encryption is a key security measure for protecting data on persistent storage. It involves converting data into a code to prevent unauthorised access. There are different types of encryption such as symmetric and asymmetric encryption. Symmetric encryption uses the same key for encryption and decryption, while asymmetric encryption uses different keys. The Advanced Encryption Standard (AES) is a widely used encryption standard that provides a high level of security.

Access controls are another important security measure. They determine who can access the data and what they can do with it. Access controls can be discretionary, mandatory, or role-based. Discretionary access control (DAC) allows the owner of the data to decide who can access it. Mandatory access control (MAC) uses a central authority to determine access, while role-based access control (RBAC) assigns access based on the user's role.

Backup systems are crucial for data protection. They create copies of data that can be restored in case of data loss or corruption. There are different types of backup such as full, incremental, and differential backup. Full backup involves copying all the data, while incremental backup only copies the data that has changed since the last backup. Differential backup copies the data that has changed since the last full backup.

Intrusion detection systems (IDS) monitor the network for malicious activities or policy violations. They can be network-based or host-based. Network-based IDS monitor the network for suspicious traffic, while host-based IDS monitor a single host for suspicious activity. IDS can also be signature-based, which detect known threats, or anomaly-based, which detect unknown threats by comparing current activity to a baseline.

In conclusion, protecting data on persistent storage involves a combination of encryption, access controls, backup systems, and intrusion detection systems. Each of these measures plays a crucial role in ensuring the security of data.