Hirschmann RS20 Reference Manual page 167

Redundancy
Parameter Meaning
s
MRP Switches the MRP compatibility on/off.
compatibilit MRP compatibility enables RSTP to be
y used within an MRP-Ring and when
coupling RSTP segments to an MRP-
Ring. The prerequisite is that all devices in
the MRP-Ring must support MRP
compatibility.
BPDU Switches the BPDU Guard function on/off.
Guard If BPDU Guard is switched on, the device
automatically activates the function for
edge ports (with the setting "Admin Edge
Port" true).
When such a port receives any STP-
BPDU, the device sets the port status
"BPDU Guard Effect" to true and the
transmission status of the port to
discarding(see table
Thus the device helps you protect your
network at terminal device ports from
incorrect configurations or attacks with
STP-BPDUs that try to change the
topology.
Table 105:Global Spanning Tree settings, local bridge parameters
Note: If you combine RSTP with an MRP-Ring, you must give the devices in
the MRP-Ring a better (i.e. numerically lower) RSTP bridge priority than the
devices in the connected RSTP network. You thus help avoid a connection
interruption for devices outside the Ring.
Note: The parameters Forward Delay and Max Age have the following
relationship:
Forward Delay ≥ (Max Age/2) + 1
If you enter values that contradict this relationship, the device then replaces
these values with the last valid values or the default value.
RM GUI L2E
Release 8.0 05/2013
Possible values
On, Off
On, Off
111).
6.3 Spanning Tree
Default setting
Off
Off
167