iES28TG/iES28GF User Manual
71
iS5 Communications Inc.
5.4.4
iBridge
Use iBridge to connect 2 Ring networks.
5.4.5
RSTP
The Rapid Spanning Tree Protocol (RSTP) is an evolution of the Spanning Tree Protocol (STP). It provides
faster convergence of spanning tree after a topology change. The system also supports STP and will detect a
connected device that is running STP or RSTP protocol automatically.
RSTP Bridge Setting
The RSTP function can be disabled, STP or RSTP and parameters set for each port via the RSTP Setting
interface.
RSTP Bridge Setting interface
The following table describes the labels for the RSTP Setting screen.
Label
Description
Mode
The RSTP function must be chosen or disabled before configuring any
of the related parameters. Valid values are Disable STP and RSTP.
Bridge Priority (0-
61440)
A value used to identify the root bridge. The bridge with the lowest
value (highest priority) is selected as the root. If the value changes, the
switch must be rebooted. The value must be a multiple of 4096
according to the protocol standard.
Max Age (6-40)
The maximum age of the information transmitted by the Bridge when
it is the Root Bridge. Valid values are in the range 6 to 40 seconds, and
MaxAge must be <= (FwdDelay-1)*2
Hello Time (1-10)
The time that the Control Switch sends out the BPDU (Bridge Protocol
Data Unit) packet to verify the current status of RSTP. Enter a value
between 1 and 10.
Forwarding Delay
Time (4-30)
The delay used by STP Bridges to transit Root and Designated Ports to
Forwarding (used in STP compatible mode). Valid values are in the
range 4 to 30 seconds.
NOTE: Follow this rule to configure the MAX Age, Hello Time, and Forward Delay Time:
2 x (Forward Delay Time value –1) ≥ Max Age value ≥ 2 x (Hello Time value +1)
