Cisco Catalyst 4500 Series Software Configuration Guide

35-2
Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS 15.2(5)Ex
Chapter 35 Configuring Layer 3 Interfaces
About Layer 3 Interfaces
This section contains the following subsections:
• Logical Layer 3 VLAN Interfaces, page 35-2
• Physical Layer 3 Interfaces, page 35-2
• Understanding SVI Autostate Exclude, page 35-3
• Understanding Layer 3 Interface Counters, page 35-3
Logical Layer 3 VLAN Interfaces
The logical Layer 3 VLAN interfaces provide logical routing interfaces to VLANs on Layer 2 switches.
A traditional network requires a physical interface from a router to a switch to perform inter-VLAN
routing. The Catalyst 4500 series switch supports inter-VLAN routing by integrating the routing and
bridging functions on a single Catalyst 4500 series switch.
Figure 35-1 shows how the routing and bridging functions in the three physical devices of the traditional
network are performed logically on one Catalyst 4500 series switch.
Figure 35-1 Logical Layer 3 VLAN Interfaces for the Catalyst 4500 Series Switch
Physical Layer 3 Interfaces
The physical Layer 3 interfaces support capabilities equivalent to a traditional router. These Layer 3
interfaces provide hosts with physical routing interfaces to a Catalyst 4500 series switch.
Figure 35-2 shows how the Catalyst 4500 series switch functions as a traditional router.
L2 Switch L2 Switch
Router
Host 1 Host 2
Traditional network topology for routing
between VLANS
Host 1 Host 2
Logical Inter-VLAN routing on a single
Catalyst 4500 series switch
Routing
VLAN1 VLAN2
VLAN1 VLAN2
94169
Interface Ethernet
1.1.1.1
Interface VLAN1
1.1.1.1
Interface VLAN2
2.1.1.1
Interface Ethernet
2.1.1.1

Cisco Catalyst 4500 Series Specifications

General

Series	Catalyst 4500 Series
Category	Switch
Layer Support	Layer 2, Layer 3
Form Factor	Modular chassis
Stackable	No
Chassis Slots	3, 6, 7, 10
Power Supply Options	AC, DC
Redundancy	Power supply, Supervisor engine
Network Management	Cisco IOS Software CLI, SNMP, Cisco Prime Infrastructure
Features	Security, QoS
Port Density	Up to 384 ports per chassis
Security Features	802.1X, ACLs, DHCP Snooping, Dynamic ARP Inspection, IP Source Guard
Supervisor Engine	8-E