D-Link DGS-3308 Series User Manual page 186

Items on the screen above include:
Group Name – The group name of the Spanning Tree group to be added.
Status – Allows STP to be Enabled or Disabled.
Max Age: [6..40 sec] – The maximum time (in seconds) a device can wait without receiving a configuration
message before attempting to reconfigure. All device ports (except for designated ports) should receive
configuration messages at regular intervals. Any port that ages out STP information (provided in the last
configuration message) becomes the designated port for the attached LAN. If it is a root port, a new root port is
selected from among the device ports attached to the network.
The minimum value is the higher of 6 or [2 x (Hello Time +1)].
The maximum value is the lower of 40 or [2 x (Forward Delay –1)].
Hello Time: [1..10 sec] – The time interval (in seconds) at which the root device transmits a configuration
message.
Forward Delay:[4..30 sec] – The maximum time (in seconds) the root device will wait before changing states
(i.e., from the listening to learning to forwarding). This delay is required because every device must receive
information about topology changes before it starts to forward packets. In addition, each port needs time to listen
for conflicting information that would make it return to a blocking state; otherwise, temporary data loops might
result.
Maximum value is 30
Minimum value is 4 [(Max. Age/ 2) +1]
Figure 7-40. STP Group Configuration – Add screen
8-port Gigabit Ethernet Switch User's Guide
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