Cisco Systems ME 3400 Layer 2 VPN Application

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Cisco ME 3400 Ethernet Access Switch Software Configuration Guide

OL-9639-06

Chapter 1 Overview Network Configuration Examples

Figure 1-1 Cisco ME Switches in a Multidwelling Configuration

Layer 2 VPN Application

Enterprise customers need not only high bandwidth, but also the ability to extend their private network

across the service provider’s shared infrastructure. With Ethernet in the WAN network, service providers

can meet the bandwidth requirements of enterprise customers and use VPN features to extend customers’

networks.

Enterprise customers can use Layer 2 VPN to transparently move any type of traffic across a

service-provider network, and create virtual pipes across the service provider infrastructure. In contrast

to Layer 3 VPN service, Layer 2 VPN lowers operational expenses by minimizing enterprise user-facing

provider edge (UPE) switch configuration and management. You can use Cisco ME 3400 switches to

form Layer 2 VPNs so that customers at different locations can exchange information through a

service-provider network without requiring dedicated connections.

In Figure 1-2, Cisco ME 3400 switches are used as UPEs in customer sites connected to

customer-premises equipment (CPE) switches. The switches can tag customer traffic with the

service-provider VLAN ID on top of the customer’s IEEE 802.1Q tag. By supporting double tags, the

Cisco ME 3400 switch provides a virtual tunnel for each customer and prevents VLAN ID overlaps

between customers. In addition to data-plane separation, the Cisco ME 3400 switch can also tunnel the

customer’s control protocols. With Layer 2 protocol tunneling, the switch can encapsulate each

customer’s control-plane traffic and send it transparently across the service-provider network.

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Catalyst 6500 switches

Cisco routers

Cisco ME switches

Home access gateways

PC PC

Set-top boxSet-top box