Because Server A resides in VLAN 10 and Server B resides in VLAN 20, traffic between them cannot remain a purely Layer 2 switched flow; it must be routed between the two VLANs, which on Switch 1 means the packet traverses the switch's internal routing engine (via an IRB interface) between the ingress and egress switching stages. Junos processes firewall filters along this path in a strict, layered order that mirrors the packet's actual journey through the device. First, any filter applied at the physical ingress port level (Rx-Port) is evaluated as the frame first arrives on ge-0/0/10. Next, any filter applied to the ingress VLAN (Rx-VLAN, i.e., VLAN 10) is evaluated as the frame is classified into its source broadcast domain. Because the destination subnet requires routing, the packet is then handed to the routing engine, where any input/ingress routed filter (Rx-Router) applied to the receiving IRB interface is evaluated next, followed by any output/egress routed filter (Tx-Router) applied as the now-routed packet is handed from the routing engine back out toward VLAN 20. Finally, the packet passes through any egress VLAN filter (Tx-VLAN, for VLAN 20) and then the egress physical port filter (Tx-Port) on ge-0/0/20 immediately before transmission to Server B. This complete six-stage sequence — Rx-Port, Rx-VLAN, Rx-Router, Tx-Router, Tx-VLAN, Tx-Port — reflects every filter-evaluation checkpoint a routed, inter-VLAN packet passes through on an EX Series Layer 3 switch. Reference topics: Junos Enterprise Switching – Layer 2 Switching and Firewall Filter Processing Order for Routed VLAN Traffic.