A Virtual Local Area Network (VLAN) is a networking technology used to logically segment a single physical network into multiple, distinct broadcast domains. Devices within a VLAN can communicate with each other as if they were on their own separate physical network, but they are isolated from devices in other VLANs. This segmentation is achieved at Layer 2 of the OSI model and is managed through network switches. It enhances security, improves network performance by reducing broadcast traffic, and simplifies network administration by grouping users and devices logically rather than by physical location.

A. MAC: A Media Access Control (MAC) address is a unique hardware identifier for a network interface, used for device-level addressing, not for segmenting networks.

C. NIC: A Network Interface Card (NIC) is the physical hardware component that allows a device to connect to a network; it does not perform logical segmentation.

D. DSL: Digital Subscriber Line (DSL) is a wide area network (WAN) technology used to provide internet connectivity over telephone lines, not for segmenting a local network.

1. IEEE Std 802.1Q™-2018

"IEEE Standard for Local and metropolitan area networks—Bridges and Bridged Networks."

Section 3.267

VLAN: Defines a VLAN as "A Virtual Local Area Network; a broadcast domain created by a set of rules in a Bridge." This standard is the foundational document defining how VLANs operate to logically segment networks.

2. Tanenbaum

A. S.

& Wetherall

D. J. (2011). Computer Networks (5th ed.). Pearson Education.

Section 4.7.4

Virtual LANs: "The solution to this problem is to use VLANs... a switch can be configured to have some ports belong to VLAN 1

others to VLAN 2

and so on. Each VLAN is a separate broadcast domain." This academic textbook explicitly states VLANs create separate broadcast domains for logical segmentation.

3. Kurose

J. F.

& Ross

K. W. (2021). Computer Networking: A Top-Down Approach (8th ed.). Pearson.

Section 6.4.2

VLANs: "A VLAN is a switch-based technology that allows creating multiple logical broadcast domains on a single physical switch infrastructure... Traffic from one VLAN can only reach other VLANs by passing through a router." This university-level textbook confirms VLANs as a method for logical segmentation managed by switches.