(ISC)2 Certified in Cybersecurity Practice Exam

What is a VLAN?

1. A secure network protocol

2. A physical separation of network devices

3. A logical group of devices appearing on the same LAN

4. An encrypted communication channel

The correct answer is: A logical group of devices appearing on the same LAN

A VLAN, or Virtual Local Area Network, is a method for creating logically distinct networks within a physical network infrastructure. This means that devices on a VLAN can communicate as if they were on the same physical network even though they may be located on different segments of the network. This logical grouping allows for better traffic management, improved security, and simplified network administration. By using VLANs, network administrators can effectively segregate network traffic without requiring additional physical devices, such as switches or routers. For example, different departments within an organization, such as HR and IT, can be kept on separate VLANs to enhance security and reduce broadcast traffic. Each VLAN has its own broadcast domain, which means that broadcast messages sent by one VLAN will not be received by devices in another, thereby improving performance. The other choices lack the defining characteristics of a VLAN. A secure network protocol refers to standards like HTTPS or IPsec, which focus on encrypting data in transit. A physical separation of network devices suggests a more traditional approach to network design, relying on distinct physical segments. An encrypted communication channel pertains to the security measures taken to protect data confidentiality and integrity, rather than how devices are logically organized within a network.