A Flexible PIC Concentrator (FPC) occupies two DPC slots on an MX Series router. The router has six dedicated DPC slots that are numbered 0 through 5, bottom to top. Up to three FPCs can be installed horizontally on the front of the router (see Figure 1). The interface corresponds to the lowest numbered DPC slot for which the FPC is installed.
Figure 1: FPC Installed in the MX480 Router Chassis

Figure 2 shows the typical FPCs supported on the MX480 router.
Figure 2: Typical FPCs Supported on the MX480 Router

If a slot is not occupied by a DPC, an FPC, or an SCB, a blank panel must be installed to shield the empty slot and to allow cooling air to circulate properly through the router.
Each FPC supports up to two PICs. On an FPC2, one Packet Forwarding Engine receives incoming packets from the PICs installed on the FPC and forwards them through the switch planes to the appropriate destination port. On an FPC3, two Packet Forwarding Engines receive incoming packets from the PICs installed on the FPC and forwards them through the switch planes to the appropriate destination port. The FPCs interface with the power supplies and SCBs.
FPCs are hot-removable and hot-insertable, as described in MX480 Component Redundancy. When you install an FPC into a functioning router, the Routing Engine downloads the FPC software, the FPC runs its diagnostics, and the PICs, housed on the FPC, are enabled. Forwarding continues uninterrupted during this process. When you remove or install an FPC, packet forwarding between other DPCs or FPCs is not affected.
Each FPC consists of the following components: