ZyXEL Communications Corporation VSG1435B101 Manuel D’Utilisation

Chapter 6 Broadband

VSG1435-B101 Series User’s Guide

This section provides some technical background information about the topics 
covered in this chapter.

Be sure to use the encapsulation method required by your ISP. The ZyXEL Device 
supports the following methods.

The ZyXEL Device supports PPPoE (Point-to-Point Protocol over Ethernet). PPPoE is 
an IETF Draft standard (RFC 2516) specifying how a personal computer (PC) 
interacts with a broadband modem (DSL, cable, wireless, etc.) connection. The 
PPPoE option is for a dial-up connection using PPPoE.

For the service provider, PPPoE offers an access and authentication method that 
works with existing access control systems (for example RADIUS).

One of the benefits of PPPoE is the ability to let you access one of multiple network 
services, a function known as dynamic service selection. This enables the service 
provider to easily create and offer new IP services for individuals.

Operationally, PPPoE saves significant effort for both you and the ISP or carrier, as 
it requires no specific configuration of the broadband modem at the customer site.

By implementing PPPoE directly on the ZyXEL Device (rather than individual 
computers), the computers on the LAN do not need PPPoE software installed, 
since the ZyXEL Device does that part of the task. Furthermore, with NAT, all of 
the LANs’ computers will have access.

PPPoA stands for Point to Point Protocol over ATM Adaptation Layer 5 (AAL5). A 
PPPoA connection functions like a dial-up Internet connection. The ZyXEL Device 
encapsulates the PPP session based on RFC1483 and sends it through an ATM PVC 
(Permanent Virtual Circuit) to the Internet Service Provider’s (ISP) DSLAM (Digital 
Subscriber Line (DSL) Access Multiplexer). Please refer to RFC 2364 for more 
information on PPPoA. Refer to RFC 1661 for more information on PPP.