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Cisco 3200 Series Router Hardware Reference
OL-5816-10
Appendix C Switch Port Functionality
Port-Based VLAN
Figure C-1 Traditional LAN Segmentation versus VLAN Segmentation
Port-Based VLANBy default, the 10/100 Fast Ethernet interfaces on the FESMIC are defaulted to Layer 2 switch ports and
all four interfaces belong to VLAN 1. You can partition the switch ports to belong to different VLAN
groups by using the switchport vlan access <vlan-id> command. The following is a brief function
description of a FESMIC port-based VLAN:
• Each VLAN has its own MAC address table.
• Packets received are forwarded only to ports that are members of the same VLAN as the receiving
port. VLAN partitions provide hard firewalls for all traffic in different VLANs.
• A VLAN comes into existence when a user adds a VLAN to the local VLAN database. A maximum
of 32 VLANs are supported. VLAN IDs can range from 1 to 1005.
• By default, a spanning tree instance is created for each VLAN.
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LAN3
LAN2
LAN1
Shared hub
Floor 1 L2 Switch
L2 Switch
Router
Router
Shared hub
Shared hub
Traditional LAN Segmentation Virtual LAN Segmentation
Floor 2
Floor 3
VLAN1 VLAN2 VLAN3
L2 Switch