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Pppoe, Appendix d pppoe, Pppoe, see – ZyXEL Communications P-2002 User Manual

Page 131

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P-2002 Series User’s Guide

Appendix D

131

A

P P E N D I X

D

PPPoE

PPPoE in Action

An ADSL modem bridges a PPP session over Ethernet (PPP over Ethernet, RFC 2516) from
your computer to an ATM PVC (Permanent Virtual Circuit) which connects to a DSL Access
Concentrator where the PPP session terminates (see

Figure 66 on page 132

). One PVC can

support any number of PPP sessions from your LAN. PPPoE provides access control and
billing functionality in a manner similar to dial-up services using PPP.

Benefits of PPPoE

PPPoE offers the following benefits:

It provides you with a familiar dial-up networking (DUN) user interface.

It lessens the burden on the carriers of provisioning virtual circuits all the way to the ISP on
multiple switches for thousands of users. For GSTN (PSTN and ISDN), the switching fabric
is already in place.

It allows the ISP to use the existing dial-up model to authenticate and (optionally) to provide
differentiated services.

Traditional Dial-up Scenario

The following diagram depicts a typical hardware configuration where the computers use
traditional dial-up networking.