PBR:
- Destination based routing systems make it quite hard to change the routing behavior of specific traffic. With PBR, a network engineer has the ability to dictate the routing behavior based on a number of different criteria other than destination network, including source or destination network, source or destination address, source or destination port, protocol, packet size, and packet classification among others.
- Policy-based routing adds flexibility and control that other routing techniques do not. It give you a level of control that a routing protocol by itself does not.
- With flexibility, there is typically a cost and in this case its scalability and manageability.
- It is a great tool but not one to be used for all cases. When you have a need to forward base on something other than destination, then PBR is your answer.
- In a way, it allows traffic engineering at interface level. It allows to route the packets over specific traffic engineered paths, which provide the desired QoS through the network.
