Allied Telesis AT-S25 - Manual (Page 231)

AT-S25 Management Software User’s Guide
231
Bridge Max Age The length of time after which stored bridge protocol
data units (bpdus) are deleted by the bridge. All bridges
in a bridged LAN use this aging time to test the age of
stored configuration messages called bridge protocol
data units (BPDUs).
For example, if you use the default 20, all bridges delete
current configuration messages after 20 seconds. This
parameter can be from 6 to 40 seconds. The default is
20 seconds.
In selecting a value for maximum age, the following
must be observed:
• MaxAge must be more then [2 x (HelloTime + 1)]
• MaxAge must be less then [2 x (ForwardingDelay - 1)]
Bridge
Identifier The MAC address of the bridge. The bridge identifier is
used as a tie breaker in the selection of the root bridge
when two or more bridges have the same bridge
priority value.
This value cannot be changed.
Root Bridge The MAC address of the bridge functioning as the root
bridge in the spanning tree domain. This value is for
viewing purposes only and cannot be changed.
Root Priority The priority number of the root bridge. This value is for
viewing purposes only and cannot be changed.
Port Priority
or
Priority
This parameter is used as a tie breaker when two or
more ports are determined to have equal costs to the
root bridge. The range is 0 to 240 in increments of 16.
The default value is 8 (priority value 128).
For a list of the increments, refer to Table 4, Port
Priority Value Increments on page 94.
Port Cost
or
Cost
The rapid spanning tree algorithm uses the cost
parameter to decide which port provides the lowest
cost path to the root bridge.
For an explanation of this parameter, refer to Table 3,
Auto-Detect Port Costs on page 93.
Point-to-Point
or
P2P
This parameter defines whether the port is functioning
as a point-to-point port.
This parameter only applies to RSTP. For an explanation
of this parameter, refer to Point-to-Point Ports and
Edge Ports on page 95.
Table 8 STP and RSTP Parameters
PARAMETER DESCRIPTION