Cisco Systems 520 series manual PPPoA, Configuration Tasks

Chapter 4 Configuring PPP over ATM with NAT

Configure the Dialer Interface

In this scenario, the small business or remote user on the Fast Ethernet LAN can connect to an Internet service provider (ISP) using the following protocols on the WAN connection:

•Asymmetric digital subscriber line (ADSL) over plain old telephone service (POTS) using the Cisco Secure Router 520 ADSL-over-POTS routers

•ADSL over integrated services digital network (ISDN) using the Cisco Secure Router 520 ADSL-over-ISDN routers

The Fast Ethernet interface carries the data packet through the LAN and off-loads it to the PPP connection on the ATM interface. The ATM traffic is encapsulated and sent over the ADSL or ISDN lines. The dialer interface is used to connect to the ISP.

PPPoA

The PPPoA Client feature on the router provides PPPoA client support on ATM interfaces. A dialer interface must be used for cloning virtual access. Multiple PPPoA client sessions can be configured on an ATM interface, but each session must use a separate dialer interface and a separate dialer pool.

A PPPoA session is initiated on the client side by the Cisco Secure Router 520 Series router.

NAT

NAT (represented as the dashed line at the edge of the Cisco router) signifies two addressing domains and the inside source address. The source list defines how the packet travels through the network.

Configuration Tasks

Perform the following tasks to configure this network scenario:

•Configure the Dialer Interface

•Configure the ATM WAN Interface

•Configure DSL Signaling Protocol

•Configure Network Address Translation

An example showing the results of these configuration tasks is shown in the “Configuration Example” section on page 4-9.

Configure the Dialer Interface

The dialer interface indicates how to handle traffic from the clients, including, for example, default routing information, the encapsulation protocol, and the dialer pool to use. It is also used for cloning virtual access. Multiple PPPoA client sessions can be configured on an ATM interface, but each session must use a separate dialer interface and a separate dialer pool.

Cisco Secure Router 520 Series Software Configuration Guide

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