How Pppoe Works; Bcm50A Integrated Router As A Pppoe Client; Figure 132 Single-Pc Per Router Hardware Configuration - Nortel BCM50a Configuration Manual

226 Appendix D PPPoE

Figure 132 Single-PC per router hardware configuration

How PPPoE works

The PPPoE driver makes the Ethernet appear as a serial link to the PC and the PC
runs PPP over the Ethernet, while the modem bridges the Ethernet frames to the
Access Concentrator (AC). Between the AC and an ISP, the AC acts as an L2TP
(Layer 2 Tunneling Protocol) LAC (L2TP Access Concentrator) and tunnels the
PPP frames to the ISP. The L2TP tunnel is capable of carrying multiple PPP
sessions.
With PPPoE, the VC (Virtual Circuit) is equivalent to the dial-up connection and
runs between the modem and the AC, as opposed to all the way to the ISP.
However, the PPP negotiation is between the PC and the ISP.

BCM50a Integrated Router as a PPPoE client

When using the BCM50a Integrated Router as a PPPoE client, the PCs on the
LAN see only the Ethernet and are not aware of the PPPoE. This alleviates the
administrator from having to manage the PPPoE clients on the individual PCs.
N0115791
BCM50a Integrated Router