Nortel 2000, Using Manual

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104 Chapter 2 Network configuration
208700-B
IEEE 802.1Q VLAN workgroups
Business Policy Switches support up to 64 VLANs (maximum of 48 MAC source
address-based VLANs) with IEEE 802.1Q tagging available per port. With
software version 1.2, the BPS 2000 supports up to 256 VLANs (maximum of 48
MAC source addressed-based VLANs.)
Ports are grouped into broadcast domains by assigning them to the same VLAN.
Frames received in one VLAN can only be forwarded within that VLAN, and
multicast frames and unknown unicast frames are flooded only to ports in the
same VLAN.
Setting up virtual LANs (VLANs) is a way to segment networks to increase
network capacity and performance without changing the physical network
topology (
Figure 17 ). With network segmentation, each switch port connects to a
segment that is a single broadcast domain. When a switch port is configured to be
a member of a VLAN, it is added to a group of ports (workgroup) that belong to
one broadcast domain.
The Business Policy Switch allows you to assign ports to VLANs using the
console, Telnet, Web-based management, CLI, or an appropriate SNMP-based
application, such as the Device Manager. You can assign different ports (and
therefore the devices attached to these ports) to different broadcast domains. This
feature allows network flexibility because you can reassign VLANs to
accommodate network moves, additions, and changes, eliminating the need to
change physical cabling.
Note:
For guidelines on configuring VLANs, STGs, and MLT, refer to
Chapter 1.
Note:
Only standalone or pure stacks of BPS 2000 support 256 VLANs.
A mixed stack that consists of BPS 2000 and BayStack 450 switches has
only 64 VLANs. Refer to Chapter 1 for more information on using 256
VLANs.