User Manual

AirWorks AWK-3131A Web Console Configuration
3-26
RSTP Settings (for Master or Slave mode only)
AWK-3131A supports IEEE802.1D Spanning Tree Protocol and IEEE802.1w Rapid STP standards. In addition to
eliminating unexpected path looping, STP/RSTP can provide a backup path recovery if a wired/ wireless path
fails accidentally. The reliability and availability can increase because this fail-over function.
AWK-3131A’s STP/RSTP feature is disabled by default. To be completely effective, you must enable RSTP/STP
on every AWK-3131A connected to your network. If AWK-3131A plays a Slave role, which is connected to a
device (PLC, RTU, etc.) as opposed to network switch equipment, it is not necessary to enable STP/RSTP. The
reason is that it will cause unnecessary negotiation. AWK-3131As support STP/RSTP in Master or Slave mode
only.
The following figures indicate which Spanning Tree Protocol parameters can be configured. A more detailed
explanation of each parameter is given below the figure.
RSTP status
This field will appear only when selected to operate STP/RSTP. It indicates whether this AWK-3131A is the Root
of the Spanning Tree (the root is determined automatically) or not.
Bridge priority
Setting Description Factory Default
Numerical value
selected
by user
You can increase the bridge priority by selecting a lower
number. A higher bridge priority brings a greater chance of
being established as the root of the Spanning Tree topology.
32768
Hello time
Setting Description Factory Default
Numerical value input
by user
(1 – 10 seconds)
The root of the Spanning Tree topology periodically sends out a
“hello”
message to other devices on the network to check if the
topology is healthy. Hello time indicates how often the root
sends hello messages.
2 (seconds)
Forwarding delay
Setting Description Factory Default
Numerical value input
by user
(4 – 30 seconds)
The amount of time this device waits before checking to see if it
should change to a different topology.
15 (seconds)
Max. age
Setting Description Factory Default
Numerical value input
by user
(6 – 40 seconds)
As a non-root role, if the device has not received a hello
message from the root longer than Max. age, it will reconfigure
itself as a root. Once two or more devices on the network are
recognized as a root, the devices will renegotiate to set up a
20 (seconds)