Vlan Membership Inference - 3Com 3C15500 - Network Director User Manual

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VLAN membership inference

First, some definitions:
A VLAN-unaware item is:
a device that doesn't support VLANs
a device that supports VLANs but has no VLANs configured
a device that supports VLANs, with exactly one VLAN configured and
all ports using untagged traffic for that VLAN i.e. factory-default
switches with all ports on the default VLAN.
A VLAN-aware item is any device that does not conform to one of the
above rules.
If a port is a member of a VLAN then 3Com Network Director will infer
that all VLAN-unaware devices hanging off that port are also members of
the same VLAN. For example, consider the network in
Figure 263 VLAN Membership Inference
"Discovering the Network"
Key Concepts 509
on page 91.
Figure 263 below.