HP Network Direr Software Products manual For further information see Discovering the Network on

Key Concepts 509

For further information see “Discovering the Network” on page 91.

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 below.

Figure 263 VLAN Membership Inference