Specifications

CHAPTER 4

InterVLAN Routing

In comparison, Multilayer Switching (MLS) uses aa Ternary Content Addressable Memory (TCAM) table to store infor-

mation needed by Layer 3 and higher processing. This might include QoS and ACLs. Values in the TCAM table include

ternary values (0, 1, or wildcard). An exact match is not required—the longest match is considered a hit.

MLS Interfaces

A multilayer switch can have the following types of interfaces:

n Layer 2 Interface: Either an access port assigned to a VLAN or a trunk port.

n Switch Virtual Interface (SVI): A virtual, software interface for the VLAN itself. Can be either a Layer 2 interface

or a Layer 3 interface.

n Routed Interface: A physical interface that is not associated with a VLAN and acts like a router port.

SVI Configuration

A default SVI for VLAN 1 is automatically created in the switch. To create an SVI use the command interface vlan#.

Configure an IP address on the SVI to make it a Layer 3 interface. SVIs are used to:

n Route or fallback bridge between VLANs.

n Provide a default gateway for users in that VLAN.

n Route traffic into or out of its associated VLAN.

n Provide an IP address for connectivity to the switch itself.

n Provide an interface for routing protocols.

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CCNP SWITCH 642-813 Quick Reference by Denise Donohue

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