Pppoe-Based Vlan Design Example - Avaya 8800 Planning And Engineering

learns its source IP address, the end-user traffic is appropriately classified into the subnet-
based VLAN.
The switch supports a maximum number of 200 subnet-based VLANs.

PPPoE-based VLAN design example

You can connect multiple Ethernet devices to a remote site through a device (such as a modem)
using Point-to-Point Protocol over Ethernet (PPPoE). PPPoE allows multiple users to share a
common Internet connection. For more information, see RFC 2516: Point-to-Point Protocol
over Ethernet.
This example shows how to use PPPoE protocol-based VLANs to redirect PPPoE Internet
traffic to an Internet service provider (ISP) network while IP traffic is sent to a routed network.
Use this design in a service provider application to redirect subscriber Internet traffic to a
separate network from the IP routed network. The design also applies to enterprise networks
that need to isolate PPPoE traffic from the routed IP traffic, even when this traffic is received
on the same VLAN.
The following figure shows the network design that achieves the following goals:
• Users can generate IP and PPPoE traffic. IP traffic is routed, and PPPoE traffic is bridged
to the ISP network. If any other type of traffic is generated, it is dropped by the Layer 2
switch or the Avaya Ethernet Routing Switch 8800/8600 (when users are attached directly
to the 8800/8600).
• Each user is assigned their own VLAN.
• Each user has two VLANs when directly connected to the Avaya Ethernet Routing Switch
8800/8600: one for IP traffic and the other for PPPoE traffic.
• PPPoE bridged traffic preserves user VLANs.
Planning and Engineering — Network Design

PPPoE-based VLAN design example

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