SonicWall Switch Getting Started Guide
Configuring from the Firewall
32
Adding a VLAN
A Virtual LAN (VLAN) is a group of ports that form a logical Ethernet segment on a Layer 2 Switch to provide
better administration, security, and management of traffic. A VLAN is a network topology configured according
to a logical scheme rather than a physical layout. When you use a VLAN, users can be grouped by logical
function instead of physical location. All ports that frequently communicate with each other are assigned to the
same VLAN, regardless of where their location in the network. VLANs let you logically segment your network
into different broadcast domains allowing the grouping of ports with related functions into their own separate,
logical LAN segments on the same Switch. This allows broadcast packets to be forwarded only between ports
within the VLAN, thus avoiding broadcast packets being sent to all the ports on a single Switch. A VLAN also
increases network performance by limiting broadcasts to a smaller, more manageable logical broadcast
domain. By limiting traffic to specific broadcast domains, VLANs improve security.
Each VLAN in a network has an associated VLAN ID, which appears in the IEEE 802.1Q tag in the Layer 2 header
of packets transmitted on a VLAN. The IEEE802.1Q specification establishes a standard method for tagging
Ethernet frames with VLAN membership information. The key for IEEE802.1Q to perform its functions is in its
tags. 802.1Q-compliant Switch ports can be configured to transmit tagged or untagged frames. A tag field
containing VLAN information can be inserted into an Ethernet frame. When using 802.1Q VLAN configuration,
you configure ports to be a part of a VLAN group. When a port receives data tagged for a VLAN group, the data
is discarded unless the port is a member of the VLAN group.
Adding a VLAN Interface:
Add a VLAN by adding a virtual interface under the uplink to the firewall.
1 Navigate to
Switch Controller > Switches
.
2 Click on
Add IPv4 Network
.
3 Define
Vlan ID
,
Address
,
Subnet Mask
and choose address assignment method:
Static
or
DHCP
.
4 Click on
OK
.
IMPORTANT:
To change the Reserved VLAN range on the firewall, do so before adding the SonicWall
Switch. If the Reserved VLAN range changes after connecting the Switch, then the Switch must be
removed and re-added.