What is the primary purpose of a network access control list (ACL)?

The primary purpose of a network access control list (ACL) is to control traffic in and out of one or more subnets. Network ACLs serve as a virtual firewall for the subnets within a VPC (Virtual Private Cloud), allowing you to specify which inbound and outbound traffic is permitted or denied. This helps maintain the security of the network by providing fine-grained control over which IP addresses and protocols can communicate with resources inside a subnet.

By configuring allow or deny rules within an ACL, you can establish security boundaries that dictate how data flows to and from specific resources. This capability is essential for protecting sensitive information and restricting access to specific services as part of a broader network security strategy.

Other options suggest purposes that are not directly related to the function of a network ACL. Enhancing application performance is more associated with content delivery or load balancing rather than access control. Managing user permissions pertains to identity and access management, which is a different aspect of security entirely. Providing encryption for data in transit refers to protecting the confidentiality of data as it travels across the network, which occurs at different layers and is not a function of ACLs. Thus, the focus of an ACL is specifically on traffic control for subnets, making it a vital component of securing a