User manual

66 www.cooperbussmann.com/wirelessresources
Cooper Bussmann 245U-E Wireless Ethernet Modem & Device Server User Manual
Rev Version 2.19
• VLAN (Pass-through Mode)—A transparent bridge in which frames are forwarded unmodified. This is the
default mode of the modem in which all frames pass transparently through the bridge regardless of whether
they are VLAN tagged or untagged. This is the most common VLAN mode and requires no VLAN configuration
at all. In VLAN Pass-through mode, access to the internal management functions is via untagged frames only,
using the IP address and subnet mask configured on the Network page.
• VLAN Aware (Bridging Mode)—A VLAN bridge that allows only explicitly configured VLANs that correspond to
the configured VLAN groups to pass data. VLAN Bridging mode is used when the tagging method is changed
in a bridged network, for example, if a frame traverses from a VLAN group to an interface that is not configured
in a VLAN. When a VLAN packet is passed to an untagged VLAN interface, the tag is removed so that the
packet can properly enter the network. Likewise, if an untagged VLAN packet is passed to a VLAN group a
VLAN tag is added. When one or more VLAN groups have been configured, VLAN Pass-through is disabled
and VLAN Aware mode is enabled.
• VLAN Aware (Routing Mode)—Same as VLAN Aware (Bridging Mode) described above, except that VLANs are
routed not bridged. When a packet is routed from one VLAN to another on a different interface. The interfaces
can be tagged or untagged and are generally on different subnets.
Enabling VLANs will allow the module to facilitate a number of possible VLAN topologies, such as:
• Segregating a wireless network into multiple virtual networks.
• Functioning as the wireless backbone on a VLAN trunk.
• Enabling a wireless network or part of the wireless network to form a VLAN trunk.
• Defining multiple virtual networks, each with a different priority to define traffic class based forwarding behavior
over the radio channel.
Each module can be set up to accept different networks by configuring VLAN groups and having the interfaces
(such as Ethernet, Wireless, or WDS repeater) configured to accept or reject tagged or untagged communications
frames.
Operation
VLAN Pass-through is enabled by default in the modem. No VLAN configuration is needed and modem will pass
any VLAN tagged frames. To initiate VLAN bridge or router operation, VLAN Aware mode must be enabled on the
VLAN page.
Figure 67 VLAN Pass-through
When VLAN Aware is enabled a default “Management VLAN Group” is created bridging the Ethernet and wireless
interfaces and configuring both with untagged frames. The “Management IP” and “Management Netmask”