Nortel business policy switch 2000 User Manual page 72

segment. Although Ethernet switches and bridges divide a network into smaller
collision domains, they do not affect the broadcast domain. In simple terms, a
virtual local area network (VLAN) provides a mechanism to fine-tune broadcast
domains.
Your Business Policy Switch allows you to create three types of VLANs:
• IEEE 802.1Q port-based VLANs
A port-based VLAN is a VLAN in which the ports are explicitly configured to
be in the VLAN. When you create a port-based VLAN, you assign a Port
VLAN Identifier (PVID) and specify which ports belong to the VLAN. The
PVID is used to coordinate VLANs across multiple switches.
In software version 1.1, automatic PVID automatically sets the PVID when
you configure a port-based VLAN. The PVID value will be the same value as
VLAN. The user can also manually change the PVID value.
The default setting for AutoPVID is Off; you must enable this feature.
• Protocol-based VLANs
A protocol-based VLAN is a VLAN in which you assign your switch ports as
members of a broadcast domain, based on the protocol information within the
packet. Protocol-based VLANs can localize broadcast traffic and assure that
only the protocol-based VLAN ports are flooded with the specified protocol
type packets. The maximum number of available protocols is 14.
• MAC source address (SA)-based VLANs
A MAC SA-based VLAN is a VLAN in which you assign switch ports as
members of a broadcast domain, based on the source MAC address
information within the packet. MAC SA-based VLANs can be used to provide
a MAC-level security scheme to organize and group different users. The
maximum number of available MAC SA-based VLANs is 48.
Policy-based VLANs are determined by the information within the packet. A port
can be a member of multiple policy-based VLANs. The order in which the rules
for VLAN classification are applied are:
Using the Business Policy Switch 2000 Version 2.0
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