Using Routing Protocols

Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2

If you use the Routing Information Protocol version 1 or 2 (RIPv1 or RIPv2) or the OSPF routing protocol in your site, you can add and configure the RIP or OSPF routing protocol components of the Routing and Remote Access service so that a demand-dial router participates in the propagation of routing information as a dynamic router. As an efficient alternative to manually configuring static routes, you can use routing protocols on each LAN interface and on each demand-dial interface that is used for a persistent site-to-site connection. You must configure dynamic routing protocols for each new router so that it can participate in the dynamic routing architecture and share its subnets.

If you use a routing protocol other than RIP or OSPF, such as the Cisco proprietary Interior Gateway Routing Protocol (IGRP) or Enhanced Interior Gateway Routing Protocol (EIGRP), configure the neighboring Cisco router for RIP or OSPF on the interface connected to the subnet that contains the dial-up or VPN router, and then configure IGRP or EIGRP on all other interfaces. You must also configure the neighboring Cisco router to redistribute the IGRP or EIGRP routes into the OSPF or RIP routing tables.

Do not use routing protocols across an on-demand site-to-site connection. The periodic announcements that most routing protocols use to propagate routing information cause one demand-dial router to call another each time an announcement occurs. For example, RIPv1, by default, announces routing information every 30 seconds. If your router incurs a long-distance charge every 30 seconds, the phone bill that results defeats the cost savings that an on-demand link is designed to provide. Instead, add routes for network IDs that are available across the demand-dial interface as static routes to the routing tables of demand-dial routers.