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Fortress Bridge: Configuration
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3.2.1 Spanning Tree ProtocolNOTE: Bridging
loops can occur on
a WLAN only when
multiple APs share the
same ESS (extended ser-
vice set).
STP is a link management protocol that prevents bridging
loops on the network while providing path redundancy. You
should enable it only in deployments in which multiple OSI
layer 2 paths to the same device(s)—i.e., bridging loops—are
possible.
STP requires multicasting capability. When STP is Enabled,
Multicast—which is configured, per radio, on the RADIO
SETTINGS screen—is automatically Enabled for both of the
Bridge’s internal radios and the fields that configure the setting
(on the RADIO SETTINGS screen) are grayed out.
The only radio to which multicasting applies is one with a Radio
Mode setting of Bridge and a Bridge Mode setting of Non-Root. If
you disable STP on the LAN SETTINGS screen, the Multicast field
(on the RADIO SETTINGS screen) of any radio so configured will
be enabled, giving you the option of turning multicasting off for
that radio. (Refer to Section 3.3.2.6 for more detail on the
multicast function of Bridge radios.)
If you enable STP on the Bridge, you should enable it across all
devices on the Bridge-secured network.
3.2.2 WAN Port EncryptionBy default, the Bridge’s WAN port is in the encrypted zone of
the Bridge-secured network, in which all traffic on the port is
encrypted.
It can be configured to be in the network’s unencrypted zone
and so to pass unencrypted traffic (cleartext).
The encrypted and unencrypted zones are mutually exclusive
and the WAN port cannot be in both zones at once.