User's Manual

Chapter 4: Access Point Configuration
General Configuration
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Teklogix 9150 Wireless Gateway User Manual
Bridge Max Age
The value of the Maximum Age parameter sent in a Configuration BPDU (Bridge
Protocol Data Unit) when the 9150 is the Root or is attempting to become the Root.
The Maximum Age is the message age at which a received configuration message is
judged “too old” and is discarded. If the selected value is too small, then occasion-
ally the spanning tree will configure unnecessarily, possibly causing temporary loss
of connectivity in the network. If the selected value is too large, the network will
take longer than necessary to adjust to a new spanning tree after a topological event
such as the restarting or crashing of a bridge or link. A conservative value is to
assume a delay variance of 2 seconds per hop. The value recommended by IEEE
802.1d is 20 seconds.
The default value is 20.
Bridge Hello Time
The time interval between the transmission of Configuration BPDUs by a 9150 that
is the Root or is attempting to become the Root.
The recommended time is 2 seconds. Shortening the time will make the protocol
more robust, in case the probability of loss of configuration messages is high.
Lengthening the time lowers the overhead of the algorithm (because the interval
between transmission of configuration messages will be larger).
The default value is 2.
Bridge Forward Delay
The value of the Forward Delay parameter sent in a Configuration BPDU when the
9150 is the Root or is attempting to become the Root.
The Forward Delay temporarily prevents a bridge from starting to forward data
packets to and from a link until news of a topology change has spread to all parts of
a bridged network. This should give all links that need to be turned OFF in the new
topology time to do so before new links are turned ON.
The default value is 15.