Allied Telesis AT-8550 - Manual (Page 98)

STP Configurations
6-4
STP Configurations
When you assign VLANs to an STPD, pay careful attention to the STP
configuration and its effect on the forwarding of VLAN traffic.
Figure 6-1 illustrates a network that uses VLAN tagging for trunk
connections. The following four VLANs have been defined:
❑ Sales is defined on Switch A, Switch B, and Switch M.
❑ Personnel is defined on Switch A, Switch B, and Switch M.
❑ Manufacturing is defined on Switch Y, Switch Z, and Switch M.
❑ Engineering is defined on Switch Y, Switch Z, and Switch M.
❑ Marketing is defined on all switches (Switch A, Switch B, Switch
Y, Switch Z, and Switch M).
Two STPDs are defined:
❑ STPD1 contains VLANs Sales and Personnel.
❑ STPD2 contains VLANs Manufacturing and Engineering.
The VLAN Marketing is a member of the default STPD, bu t not
assigned to either STPD1 or STPD2.
Figure 6-1 Multiple Spanning Tree Domains
Sales, Personnel, Marketing
STPD 1 STPD 2
Manufacturing, Engineering, Marketing
Sales, Personnel, Manufacturing, Engineering, Marketing
Switch A Switch Y
Switch Z
Switch M
Switch B
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