VLANs (Virtual Local Area Networks) are used to segment a physical network into multiple logical broadcast domains. An ARP (Address Resolution Protocol) request is a broadcast message used to map an IP address to a MAC address. By design, broadcast traffic, including ARP requests, is confined to the VLAN in which it originates and is not forwarded by the switch to other VLANs. Therefore, if PC1 and PC2 are placed in different VLANs on the same switch, they belong to separate broadcast domains. As a result, an ARP request from PC1 cannot reach PC2, and they will be unable to learn each other's MAC addresses via ARP. This is a fundamental mechanism of Layer 2 isolation provided by VLANs.

This is a True/False question. The alternative, "False," is incorrect because it contradicts the core principle of VLANs, which is to create isolated broadcast domains at Layer 2. The scenario described is a classic symptom of VLAN misconfiguration where two devices that need to communicate directly are placed in different VLANs.

1. Huawei. (2020). HCIA-Datacom V1.0 Training Material (GAUSS-DB-V1.0.0.2). Section: "VLAN Principles". This material explains that VLANs logically divide a network into different broadcast domains and that communication between VLANs requires a Layer 3 device.

2. Huawei. S Series Switches Configuration Guide - VLAN. In the documentation for switches like the S5700 series

the section on "VLAN Principles" details how VLANs isolate broadcast domains

explicitly preventing Layer 2 traffic

such as ARP broadcasts

from crossing VLAN boundaries.