Redundancy
188
7.5
Spanning Tree
RM Web
Release
6.0
07/2010
Forward
Delay
Sets the Forward Delay parameter.
In the previous STP protocol, the Forward
Delay parameter was used to delay the
status change between the statuses
disabled, discarding, learning,
forwarding. Since the introduction of
RSTP, this parameter only has a
subordinate role, because the RSTP
bridges negotiate the status change
without any specified delay.
If the local device is the root, the other
devices in the entire network take over this
value. Otherwise the local device uses the
value of the root bridge in the “Root”
column on the right.
4 - 30 s
See the note
following this table.
15 s
Max Age Sets the Max Age parameter.
In the previous STP protocol, the Max Age
parameter was used to specify the validity
of STP BPDUs in seconds. For RSTP,
Max Age signifies the maximum
permissible branch length (number of
devices to the root bridge).
If the local device is the root, the other
devices in the entire network take over this
value. Otherwise the local device uses the
value of the root bridge in the “Root”
column on the right.
6 - 40 s
See the note
following this table.
20 s
TX Hold
Count
Sets the HX Hold Count parameter.
The TX Hold Count parameter specifies
the maximum number of BPDUs that a
port may send per second. If more BPDUs
are waiting to be sent, the device rejects
the remaining ones. When the global Hello
Time has elapsed, the device sends all the
currently waiting BPDUs until the
maximum number is reached again.
1 - 40
(based on RSTP
standard: 1 - 10)
10
Parameter Meaning Possible Values Default Setting
Table 81: Global Spanning Tree settings, local bridge parameters