Port Based Vlans - Secure Computing SG300 User Manual

Removing VLANs
To remove a VLAN, click the Delete icon alongside the VLAN interface in the main
Network Setup -> Connections table.

Port Based VLANs

Note
SG560, SG565 and SG580 only.
The SG560, SG565 and SG580 have a VLAN-capable switch built in. This gives you the
flexibility to either use it as a simple switch that allows access between all ports (this is
the default), or use port based VLANs to control access between each individual port in
the switch.
This port based VLAN configuration makes it possible to assign each of the four ports its
own subnet address, declare it to be a LAN, WAN or DMZ independent of the other ports
and generally treat it as if it was a completely separate physical port.
The SG unit may also participate on an existing VLAN. When you add a VLAN interface
to connect to the existing VLAN, you may associate it with one or more of the SG unit's
ports.
Tagged and untagged VLANs
When using port based VLANs, it is important to understand the differences between
tagged and untagged VLANs.
Tagged VLAN interfaces add a VLAN header (see the VLAN Overview section earlier in
this chapter) to outgoing network packets, and only accept incoming network packets that
contain an appropriate VLAN header. Untagged VLAN interfaces do not add a VLAN
header to outgoing network packets, and do not accept incoming packets that contains a
VLAN header.
A port may be a member of either a single untagged VLAN, or one or more tagged
VLANs. A port may not be a member of both tagged and untagged VLANs.
Once switch A has had port based VLANs enabled, ports that have not been explicitly
assigned to one or more VLANs are assigned to the default VLAN. The default VLAN is
untagged.
Network Setup
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