Chapter 8. Setting Up the Network

All Juniper routers have a common job to do: Move messages and traffic across the network from the person (or application) sending the message to a specific destination. The movement of messages and traffic is called routing.

This chapter explains the basic principles of routing and how routers route traffic. It also talks about the common routing protocols used to move traffic across the network and how to set them up on your network.

Understanding Network Routing

The most basic routing concept is that of a route. Routes on a network, whether the global Internet or the network within your company, are the path that messages take to reach their destination.

The way routes are determined is similar to how you might choose to drive from your home to work. Most people know several different ways to get to work and each day choose the one that will be best because it's less congested or avoids a construction project or whatever. Network routes work the same way. The router's job is to keep track of available routes and to send network traffic along the route that it decides is best at that moment.

Most of the time, however, we tend to take the same route to work everyday. This route is unchanging, or static. On a network, you (as the administrator) may want packets from a specific router to always follow the same path to reach another router. The administrator explicitly configures these static routes on the router.

Static routes are the simplest way to direct ...

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