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.

LAN Configuration

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NETGEAR STM150EW-100NAS, UTM5EW-100NAS manual Port-Based VLANs, LAN Configuration