Understanding Filter-Based Forwarding for EX Series Switches
Administrators of Juniper Networks EX Series Ethernet Switches can use firewall filters in conjunction with virtual routing instances to specify different routes for packets to travel in their networks. To set up this feature, which is called filter-based forwarding, you specify a filter and match criteria and then specify the virtual routing instance to send packets to.
You might want to use filter-based forwarding to route specific types of traffic through a firewall or security device before the traffic continues on its path. You can also use filter-based forwarding to give certain types of traffic preferential treatment or to improve load balancing of switch traffic.