Using Routing Protocols
Applies To: Windows Server 2008, Windows Server 2008 R2
If you use Routing Information Protocol (RIP) version 1 or 2 in your site, you can add and configure the RIP routing protocol components of RRAS 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, such as Enhanced Interior Gateway Routing Protocol (EIGRP), configure the neighboring Cisco router for RIP on the interface connected to the subnet that contains the dial-up or VPN router, and then configure EIGRP on all other interfaces. You must also configure the neighboring Cisco router to redistribute the EIGRP routes into the 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 the 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 static routes for network IDs that are available across the demand-dial interface to the routing table of each demand-dial router. For more information, see Configure Static Routes in the RRAS Deployment Guide.