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ZyXEL Communications P-334W User Manual

Page 446

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Prestige 334W User’s Guide

A-2

PPPoE

Diagram A-1 Single-PC per Modem 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 it, while the
modem bridges the Ethernet frames to the Access Concentrator (AC). Between the AC and an ISP, the AC is
acting as a 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 is 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.