Cisco Routers support many dynamic routing protocols for learning routes in a complex network topology. The routing protocols supported are the following:
Each routing protocol has its own Administrative Distance (AD), which is a value representing the trustworthiness of the specific routing protocol. If a router learns a destination route from two or more routing protocols, it selects the route from the protocol having the smallest Administrative Distance.
The table below shows the default AD values for each routing protocol:
Now, if the router learns a specific destination route from both OSPF and RIP, it will select the route learned from OSPF because this protocol has a smaller AD compared to RIP (110 instead of 120).
- Configuring GRE Tunnel Through a Cisco ASA Firewall
- The Protocol of the Internet – eBGP and iBGP Tutorial and Configuration
- How to Configure Static Routing on Cisco IOS Routers (Examples)
- Redistribution Between Cisco EIGRP into OSPF and Vice Versa (Example)
- Configuring Local Username and Password on a Cisco IOS Router