M160 Internet Router Hardware Guide
FPC Components
An FPC has the following components:
FPC card carrier—Houses the ASICs,connectors, and processor subsystem.
Four I/O Manager ASICs—Parse Layer 2 and Layer 3 dataand perform
encapsulation and segmentation. The I/O Manager ASICs divide incoming
packets into 64-bytedata cells for easier processing, and reassemble the cells
for each packet afterthe forwarding decision is made for it. Enhanced FPCs
have I/O Manager ASICs capableof enhanced quality of service.
Two PacketDirector AS ICs—Transferpackets be tween the PICs and the I/O
Manager ASICs: one directs incoming packets from the PICs to the I/O
Manager ASICs, while the second directsoutgoing packets from the I/O
Manager ASICs to the PICs.
Eight identical synchronous DRAM(SDRAM) dual inline memory modules
(DIMMs)—Form the memory pool sharedwith the other FPCs installed
in the router.
Parity-protectedsynchronousSRAM(SSRAM)—Storesdatastructuresused
by the I/O Manager ASICs.
Processor subsystem—Manages packet handling in th eF PC and
communication with the SFM. It is a PowerPC 603e-based CPU with
parity-protected DRAM.
EEPROM—Stores the serialnumber and revision level of the FPC.
Two LEDs—Indicate FPC status. The LED labeled OK is green and the one
labeled FAIL is red. The LEDs for each FPC are locatedon the router craft
interface. For more information, see “FPC LEDs and Offline Button” on
page 31.
Offline button—Preparesthe FPC for removal from the router when pressed.
Like the LEDs,an offline button is located on the craft interface. For more
information, see “FPC LEDs and OfflineButton” on page 31.
Four PIC offline buttons(on FPC1 only)—Prepare each corresponding PIC
for removal fromthe FPC.
Ejector levers—Control the locking system that secures the FPC in the card
cage.
NOTE: For specificinformation about FPC components (for example, the amount of
memory available), issue the show chassis fpc command.
16 Packet Forwarding Engine