(ISC)2 Certified in Cybersecurity Practice Exam

Which device is responsible for carrying VLANs on a network?

1. Switch

2. Router

3. Firewall

4. Hub

The correct answer is: Switch

The device responsible for carrying VLANs on a network is a switch. Switches operate at Layer 2 (Data Link Layer) of the OSI model and are designed to handle the traffic between devices on the same network segment. When VLANs (Virtual Local Area Networks) are utilized, switches play a crucial role in segmenting the network traffic according to the defined VLAN IDs. By assigning different ports on the switch to specific VLANs, the switch can ensure that broadcast traffic is limited to devices within the same VLAN, enhancing performance and security. Additionally, switches support features like VLAN trunking, which allows multiple VLANs to traverse a single physical link by tagging frames with the appropriate VLAN information. This capability is fundamental for managing network segmentation and optimizing the flow of data in environments where different departments or groups require separation in the network. Other devices like routers can manage traffic between different VLANs but do not inherently carry VLANs across the network as switches do. Firewalls are primarily concerned with security and traffic filtering, while hubs, considered outdated technology, do not have the intelligence to handle VLANs, as they simply broadcast incoming data to all ports without separating traffic.