HP 600 Series, Services And Applications

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If the bridge finds a match between the destination address and a address
table entry, it compares the circuit group on which the frame was received
with the circuit group associated with the table entry. Identical circuit
groups indicate that the source and destination end nodes are located on the
same physical network. In this instance, because relay is not necessary, the
bridge drops the frame. Different circuit groups indicate that the source and
destination end nodes are not located on the same physical network. In this
instance, the bridge relays the frame on the circuit group found in the
address table.
With the spanning tree algorithm enabled, the transparent bridge ensures a
loop-free topology by cooperating with other bridges in the extended
network. The algorithm provides a single path (composed of bridges and
intervening LANs) between any two end nodes.
Spanning Tree Algorithm
The IEEE 802.1 committee has issued a standard applicable to all MAC-level
bridges. Much of this standard is concerned with the operation of bridges in
topologically complex environments which may contain parallel (also called
redundant) bridge connections between multiple LANs. Such parallel
connections cannot be tolerated within a transparent bridging environment.
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Bridging Service
Transparent Bridging
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