Users Guide

VLANs 737

VLANs

Dell EMC Networking N-Series Switches

This chapter describes how to configure VLANs, including port-based

VLANs, protocol-based VLANs, double-tagged VLANs, subnet-based VLANs,

and Voice VLANs.

The topics covered in this chapter include:

• VLAN Overview

• Default VLAN Behavior

• Configuring VLANs (Web)

• Configuring VLANs (CLI)

• VLAN Configuration Examples

VLAN Overview

By default, all ports on Dell EMC Networking N-Series switches are in the

same broadcast domain (VLAN 1). This means when any host connected to

the switch broadcasts traffic, every other device connected to the switch

receives that broadcast. All ports in a broadcast domain also forward multicast

and unknown unicast traffic to every directly connected device. Large

broadcast domains can result in network congestion, and end users might

complain that the network is slow. In addition to latency, large broadcast

domains are a greater security risk since all hosts receive all broadcasts.

Virtual Local Area Networks (VLANs) allow the administrator to divide a

broadcast domain into smaller, logical networks. Like a bridge, a VLAN switch

forwards traffic based on the layer-2 header, which is fast, and like a router, it

partitions the network into logical segments, which provides better

administration, security, and management of multicast traffic.

Network administrators have many reasons for creating logical divisions

within a network, such as department or project membership. Because

VLANs enable logical groupings, group members do not need to be physically

connected to the same switch or network segment. Some network

administrators use VLANs to segregate traffic by type so that the time-