SMC Networks SMC2552W-G2-17 manual System Configuration

6 System Configuration

designated ports. After determining the lowest cost spanning tree, it enables all root ports and designated ports, and disables all other ports. Network packets are therefore only forwarded between root ports and designated ports, eliminating any possible network loops.

Once a stable network topology has been established, all bridges listen for Hello BPDUs (Bridge Protocol Data Units) transmitted from the root bridge. If a bridge does not get a Hello BPDU after a predefined interval (Maximum Age), the bridge assumes that the link to the root bridge is down. This bridge will then initiate negotiations with other bridges to reconfigure the network to reestablish a valid network topology.

•Bridge – Enables/disables STP on the wireless bridge or repeater. (Default: Disabled)

•Bridge Priority – Used in selecting the root device, root port, and designated port. The device with the highest priority becomes the STP root device. However, if all devices have the same priority, the device with the lowest MAC address will then become the root device. (Note that lower numeric values indicate higher priority.)

•Range: 0-65535

•Default: 32768

•Bridge Max Age – 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. (Range: 6-40 seconds)

•Default: 20

•Minimum: The higher of 6 or [2 x (Hello Time + 1)].

•Maximum: The lower of 40 or [2 x (Forward Delay - 1)]

•Bridge Hello Time – Interval (in seconds) at which the root device transmits a configuration message. (Range: 1-10 seconds)

•Default: 2

•Minimum: 1

•Maximum: The lower of 10 or [(Max. Message Age / 2) -1]

•Bridge Forwarding Delay – The maximum time (in seconds) this device waits before changing states (i.e., discarding to learning to forwarding). This delay is required because every device must receive information about topology changes before it starts to forward frames. In addition, each port needs time to listen for conflicting information that would make it return to a discarding state; otherwise, temporary data loops might result. (Range: 4-30 seconds)

•Default: 15

•Minimum: The higher of 4 or [(Max. Message Age / 2) + 1]

•Maximum: 30

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