Motorola AP-7131 Series, Reference Manual

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5 - 28 WiNG 5.5 Access Point System Reference Guide
20. Refer to the MSTP Configuration field to define the following:
21. Refer to the Spanning Tree Port Cost table.
Define an Instance Index using the spinner control and then set the cost. The default path cost depends on the user defined
port speed. The cost helps determine the role of the port channel in the MSTP network. The designated cost is the cost for
a packet to travel from this port to the root in the MSTP configuration. The slower the media, the higher the cost.
Enable PortFast BPDU
Filter MSTP BPDUs are messages exchanged when controllers gather information about the
network topology during STP scan. When enabled, PortFast enabled ports do not
transmit or receive BPDU messages. 'Default' sets the PortFast BPDU Filter value to the
bridge's BPDU filter value.
Select Enable to invoke a BPDU filter for this PortFast enabled port channel.
Enable PortFast BPDU
Guard When enabled, PortFast enabled ports are forced to shut down when they receive BPDU
messages. When set to
Default sets the PortFast BPDU Guard value to the bridge's
BPDU guard value.
Enable as Edge Port Select to enable the port as an Edge Port for MSTP. An Edge Port is a port known to
connect to a LAN which has no other bridges attached to it or is directly connected to
an user device.
Link Type Select either the Point-to-Point or Shared radio button. Selecting Point-to-Point
indicates the port should be treated as connected to a point-to-point link. Selecting
Shared means this port should be treated as having a shared connection. A port
connected to a hub is on a shared link, while one connected to a access point is a point-
to-point link. Point-to-Point is the default setting.
Cisco MSTP
Interoperability Select to enable or disable interoperability with CISCO’s implementation of MSTP
which is incompatible with standard MSTP.
Force Protocol Version Select the STP protocol to use with this port. Select Not Supported to disable STP on
this port.
Guard The Root Guard mechanism prevents election of roots other than those designated as
roots in a network. When this port receives a better BPDU, port state becomes
Blocked .
It retains this state till the port no longer receives the better BPDUs and the state is
changed to
Forwarding .
Select Root to enable this feature. Select None to disable this feature.
Speed Default Path Cost
<=100000 bits/sec 200000000
<=1000000 bits/sec 20000000
<=10000000 bits/sec 2000000
<=100000000 bits/sec 200000
<=1000000000 bits/sec 20000
<=10000000000 bits/sec 2000
<=100000000000 bits/sec 200