Руководство Пользователя для Netopia 3220-h

Cayman 3220-H User’s Guide

How Your Cayman 3220-H Works

December 2000

Route flushing is especially important when a port is 
configured as a dial-in PPP interface, since the router will 
not be able to dial out to re-establish a link after it goes 
down.

If route flushing is turned off, the router does not change 
the route's status or metric when the link goes down. 
Instead, it maintains its routing table entry and freezes the 
RIP timer for the route. When the link comes back up, the 
router continues aging the route without restarting its RIP 
timer. 

Turning route flushing off is most appropriate for dial-out 
PPP interfaces, since you may want the router to hold onto 
routes it acquired dynamically over a PPP link and not time 
them out after the link closes. If the router receives a 
packet destined for a network on the other side of the 
down PPP link, it dials out to re-establish the link. 

PPP (Point-to-Point Protocol) over Ethernet is an emerging 
technology that lets a personal computer or network connect with 
a high-speed data network over a cable or xDSL modem.

PPPoE simplifies deployment of high-speed networks. PPPoE 
provides access to high-speed (xDSL or cable modem) networks 
while preserving familiar dial-up models for Internet access. 
Consequently, users and ISPs can transition from dial-up 
network access to PPPoE network access quickly and 
inexpensively.

PPPoE integrates easily into dial-up ISP infrastructure. Carriers 
and ISPs who are moving from a dial-up network base to a 
broadband network base can continue using their existing 
authentication, billing, access control, and IP address 
management models.