ZyXEL Communications ZyXEL Prestige 660R, Руководство пользователя

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Prestige 660R ADSL 2+ Access Gateway
WAN Setup 6-1
Chapter 6
WAN Setup
This chapter describes how to configure WAN settings.
6.1 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.
6.2 Metric
The metric represents the "cost of transmission". A router determines the best route for transmission by
choosing a path with the lowest "cost". RIP routing uses hop count as the measurement of cost, with a
minimum of "1" for directly connected networks. The number must be between "1" and "15"; a number
greater than "15" means the link is down. The smaller the number, the lower the "cost".
The metric sets the priority for the Prestige’s routes to the Internet. If any two of the default routes have the
same metric, the Prestige uses the following pre-defined priorities:
1. Normal
route: designated by the ISP (see section 6.5 )
2. Traffic-redirect route (see section 6.6 )
3. WAN-backup route, also called dial-backup (see section 6.6 )
For example, if the normal route has a metric of "1" and the traffic-redirect route has a metric of "2" and dial-
backup route has a metric of "3", then the normal route acts as the primary default route. If the normal route
fails to connect to the Internet, the Prestige tries the traffic-redirect route next. In the same manner, the
Prestige uses the dial-backup route if the traffic-redirect route also fails.
If you want the dial-backup route to take first priority over the traffic-redirect route or even the normal route,
all you need to do is set the dial-backup route’s metric to "1" and the others to "2" (or greater).
IP Policy Routing overrides the default routing behavior and takes priority over all
of the routes mentioned above (see the IP Policy Routing chapter).
6.3 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.