Cisco Catalyst 4500 Series, Software Configuration Manual

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C H A P T E R
20-1
Catalyst 4500 Series Switch, Cisco IOS Software Configuration Guide - Cisco IOS XE 3.9.xE and IOS 15.2(5)Ex
20
Configuring EVC-Lite
This document describes how to configure EVC-Lite, which is a lite version of the Ethernet Virtual
Connections (EVC) feature on Supervisor Engine 7L-E. The associated command pages are also
provided.
The document details:
• About EVC-Lite, page 20-1
•
How to Configure EVC-Lite, page 20-2
Note
For complete syntax and usage information for the switch commands used in this chapter, see the
Cisco IOS Command Reference Guides for the Catalyst 4500 Series Switch .
If a command is not in the Cisco Catalyst 4500 Series Switch Command Reference , you can locate it in
the Cisco IOS Master Command List, All Releases .
About EVC-Lite
Ethernet virtual circuits (EVCs) define a Layer 2 bridging architecture that supports Ethernet services.
An EVC is defined by the Metro-Ethernet Forum (MEF) as an association between two or more user
network interfaces that identifies a point-to-point or multipoint-to-multipoint path within the service
provider network. An EVC is a conceptual service pipe within the service provider network. A bridge
domain is a local broadcast domain that exists separately from VLANs.
A Catalyst 4500 series switch comprises of two bridge domains (BDs), BD 0 and BD 1. By default, all
ports belong to BD 0 and you can move them to BD 1 manually.
EVC-Lite supports 8K VLANs using the existing support of 8K Internal VLANs, segregated under the
two BDs, where each BD has its own representation of 4K VLANs.
A system can have two types of VLAN's: EVC-Lite and non EVC-Lite (the default). Ordinary VLANs
are VLANs without awareness of any BDs (the situation that exists when the feature is not enabled).
EVC-Lite VLANs are treated differently in different bridge domains (e.g the same VLAN 2 is treated
differently in BD 0 and BD 1).
A port can support both EVC-Lite and non EVC-Lite VLANs. EVC-Lite VLANs that are part of BD 1
are mapped to an internal VLAN ID as VLAN ID + 4096. Remaining VLANs are not mapped internally.