Which security measure is effective for data at rest?

Access controls and permissions are crucial security measures for protecting data at rest. This type of data refers to information that is stored on physical or virtual devices and is not actively being transferred across networks. Implementing strict access controls ensures that only authorized users or systems can access sensitive data, thereby reducing the risk of unauthorized access, data breaches, or leaks.

Access controls involve setting permissions based on user roles, ensuring that individuals have the minimum level of access necessary for their job functions. This principle of least privilege minimizes the attack surface by limiting exposure to potential threats. Moreover, effective access controls often include authentication methods, such as passwords or biometric scans, to verify users' identities before allowing them to interact with the data.

In contrast, measures like a virtual private network (VPN) focus on securing data in transit rather than data at rest. Data redundancy practices are typically more about ensuring data availability and disaster recovery than about securing data. Load balancing techniques aim to distribute workloads across multiple resources for optimal performance, rather than providing security for data storage. Therefore, access controls and permissions stand out as the most effective method for safeguarding data at rest.