RIP isn't very common any more, and without more than one router that can run it, you really won't learn anything. You should focus on things like setting up a VPN termination point, setting up ...
What type of firewall is linux. I want to use it to set up a dmz zone. Is it a stateful inspection or what. Also do you have any info on setting up dmz zones in linux. I'm using redhat 8.0.