Another reason for implementing a multi-WAN setup is that such setups make policy-based routing possible. This is a form of routing in which routing decisions are made based on administrative policies rather than other criteria such as speed. In this context, it means that pfSense can divert traffic that matches a certain firewall rule to a specific gateway. A simple example of this would be a rule that directs outbound traffic from a certain subnet (for example, the DMZ) to a certain gateway. We can also direct traffic from a specific host instead of a network, or maybe just traffic that uses a certain protocol. Another use for policy-based routing is segregating services based on their priority. You may have a high-quality connection with little bandwidth, such as a T1 connection (1.544 Mbps), and a low-quality connection with a much higher level of bandwidth, such as a typical broadband connection. You could use policy-based routing to send high-priority traffic to the T1, while leaving other permitted (but lower priority) traffic relegated to the broadband connection.