THOMSON SpeedTouch, Configuration Manual

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Chapter 6
PPPoE Relay
E-DOC-CTC-20051017-0167 v1.0
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6 PPPoE Relay
Introduction
PPPoE has become one of the standard technologies used by Internet Service
Providers (ISPs) to connect DSL customers to the Internet. This drove ISPs to
distribute PPPoE clients to end-users. Distribution and updates of PPPoE clients to
end-users makes PPPoE a heavy connection technology. ISPs asked to remove
PPPoE from the end-user side and to integrate it in the SpeedTouch™.
In order to keep backward compatibility with end-users using PPPoE clients, and be
transparent to the Broadband Remote Access Server (BRAS), the SpeedTouch™
has to relay PPPoE traffic from the end-user to the ISP. The difference between the
bridging model and the routing model is that in the bridging model the BRAS will
see as source MAC address the MAC address of each of the PCs, while in the
routing model the BRAS will see as source MAC address the MAC address of the
SpeedTouch™.
Furthermore, ISPs request that if multiple end-users are connecting using PPPoE
through the same SpeedTouch™, all connections from the SpeedTouch™ to the
DSLAM use the same ETHoA-configured ATM PVC.
This is what is called PPPoE Relaying.
Features
The PPPoE Relay is a mechanism to allow for the following features:
Simultaneous PPPoE sessions from the LAN in parallel to PPPoE sessions
from the SpeedTouch™, on the same Virtual Channel (VC).
One or multiple PPPoE sessions from the SpeedTouch™ over the LAN to the
network (for example: SpeedTouch™ connected via Ethernet over a cable
modem to the network).
Simultaneous PPPoE sessions from the LAN in parallel Routed Ethernet
sessions from the SpeedTouch™ on the same VC. The SpeedTouch™ is
capable of initiating multiple PPPoE sessions per VC.