M320 Flexible PIC Concentrator (FPC) Description

Up to eight Flexible PIC Concentrators (FPCs) install vertically in the front of the router (see Figure 1). The FPC slots are numbered left to right from FPC0 to FPC7. Depending on the FPC type, an FPC has either two or four slots into which a PIC can be installed (see M320 FPCs Supported for more information). An FPC can be installed into any FPC slot on the router, regardless of which PICs it contains.

If a slot is not occupied by an FPC, an FPC blank panel must be installed to shield the empty slot and to allow cooling air to circulate properly through the router.

Each FPC consists of the following components:

• FPC card carrier, which includes the PIC slots.
• One Packet Forwarding Engine consisting of Layer 2/Layer 3 Packet Processing ASICs, Switch Interface ASICs, Internet Processor ASICs, and an MMB, which includes the Queuing and Memory Interface ASICs.
• Midplane connectors and power circuitry.
• Processor subsystem (PMB), which includes a 288-MHz CPU, system controller, 256 MB of SDRAM, and two Fast Ethernet interfaces.
• Two LEDs, located on the craft interface above the FPC, that display the status of the FPC. For more information about the FPC LEDs, see M320 Craft Interface FPC LEDs and Online/Offline Buttons.
• FPC online/offline button, located on the craft interface above the FPC.

The 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. Each FPC contains a memory subsystem (MMB) that is managed by the Queuing and Memory Interface ASICs.

FPCs are hot-removable and hot-insertable, as described in M320 Field Replaceable Units. 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 is not affected. For FPC replacement instructions, see Replacing an M320 FPC.

Figure 1: FPC Installed in Router Chassis

The M320 router supports the following types of FPCs (see Figure 2 ):

• FPC1, Enhanced II FPC1, and Enhanced III FPC1—Rated at 4 gigabits per second (Gbps) full duplex
• FPC2, Enhanced II FPC2, and Enhanced III FPC2—Rated at 16 Gbps full duplex
• FPC3, Enhanced II FPC3, and Enhanced III FPC3—Rated at 20 Gbps full duplex

Figure 2: FPC1, FPC2, and FPC3 for the M320 Router

Figure 3 shows the Enhanced II FPCs that the M320 router supports.

Figure 3: Enhanced II FPC1, FPC2, and FPC3 for the M320 Router

Figure 4 shows the Enhanced III FPCs that the M320 router supports.

Figure 4: Enhanced III FPC1, FPC2, and FPC3 for the M320 Router