ZyXEL Communications Prestige 861H-G1, User Manual

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Prestige 861H User’s Guide
WAN Setup 7-1
Chapter 7
WAN Setup
This chapter describes how to configure WAN settings.
7.1 WAN Overview
A WAN (Wide Area Network) is an outside connection to another network or the Internet.
See the Wizard Setup chapter for more information on the fields in the WAN screens.
7.2 PPPoE Encapsulation
The Prestige 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). PPPoE provides a login and authentication method that
the existing Microsoft Dial-Up Networking software can activate, and therefore requires no new
learning or procedures for Windows users.
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 Prestige (rather than individual computers), the computers on
the LAN do not need PPPoE software installed, since the Prestige does that part of the task.
Furthermore, with NAT, all of the LANs’ computers will have access.
7.3 Traffic Shaping
Traffic shaping is an agreement between the carrier and the subscriber to regulate the average rate and
fluctuations of data transmission over an ATM network. This agreement helps eliminate congestion,
which is important for transmission of real time data such as audio and video connections.
7.3.1 ATM Traffic Classes
These are the basic ATM traffic classes defined by the ATM Forum Traffic Management 4.0
Specification.
Constant Bit Rate (CBR)
Constant Bit Rate (CBR) is an ATM traffic class that provides fixed bandwidth. CBR traffic is
generally time-sensitive (doesn’t tolerate delay). CBR is used for connections that continuously
require a specific amount of bandwidth. Examples of connections that need CBR would be high-
resolution video and voice.