NETGEAR STM150EW-100NAS Router User Manual


 
LAN Configuration
99
ProSecure Unified Threat Management (UTM) Appliance
A virtual LAN (VLAN) is a local area network with a definition that maps workstations on
some basis other than geographic location (for example, by department, type of user, or
primary application). To enable traffic to flow between VLANs, traffic needs to go through a
router, just as if the VLANs were on two separate LANs.
A VLAN is a group of computers, servers, and other network resources that behave as if they
were connected to a single network segment—even though they might not be. For example,
all marketing personnel might be spread throughout a building. Yet if they are all assigned to
a single VLAN, they can share resources and bandwidth as if they were connected to the
same segment. The resources of other departments can be invisible to the marketing VLAN
members, accessible to all, or accessible only to specified individuals, depending on how the
IT manager has set up the VLANs.
VLANs have a number of advantages:
It is easy to set up network segmentation. Users who communicate most frequently with
each other can be grouped into common VLANs, regardless of physical location. Each
group’s traffic is contained largely within the VLAN, reducing extraneous traffic and
improving the efficiency of the whole network.
They are easy to manage. The addition of nodes, as well as moves and other changes,
can be dealt with quickly and conveniently from a management interface rather than from
the wiring closet.
They provide increased performance. VLANs free up bandwidth by limiting node-to-node
and broadcast traffic throughout the network.
They ensure enhanced network security. VLANs create virtual boundaries that can be
crossed only through a router. So standard, router-based security measures can be used
to restrict access to each VLAN.
Port-Based VLANs
The UTM supports port-based VLANs. Port-based VLANs help to confine broadcast traffic to
the LAN ports. Even though a LAN port can be a member of more than one VLAN, the port
can have only one VLAN ID as its port VLAN identifier (PVID). By default, all four LAN ports
of the UTM are assigned to the default VLAN, or VLAN 1. Therefore, by default, all four LAN
ports have the default PVID 1. However, you can assign another PVID to a LAN port by
selecting a VLAN profile from the drop-down list on the LAN Setup screen.
After you have created a VLAN profile and assigned one or more ports to the profile, you
need to enable the profile to activate it.
The UTM’s default VLAN cannot be deleted. All untagged traffic is routed through the default
VLAN (VLAN1), which you need to assign to at least one LAN port.
Note the following about VLANs and PVIDs:
One physical port is assigned to at least one VLAN.
One physical port can be assigned to multiple VLANs.
When one port is assigned to multiple VLANs, the port is used as a trunk port to connect
to another switch or router.