Policy-based routing is used to change the path that a flow with a specific destination address takes out of the router. In the example below, the normal flow of VoIP traffic between the 2811 router and the 1841 router is shown:

In the following example, PBR will be applied to the 2811 router on the Fas0/0 interface, so that traffic flows through the VLAN 1 interface rather than Fa0/1. The flow will also enter the 1841 router from the VLAN 1 interface instead of Fa1. This can be visualized using NetFlow displays for the 2811 and 1841 routers.