Juniper Networks M5 - Manual (Page 30)

Packet Forwarding Engine
Quad-wide PICs, such as the 4-port Gigabit Ethernet and OC-48/STM-16 SONET/SDH PICs,
occupy all four slots in an FPC. Some quad-wide PICs might not be supported on both the M5
and M10 routers; for more information, see the M5 and M10 Internet Routers PIC Guide.
Both regular and quad-wide PICs are hot-removable and hot-insertable. A removed PIC
no longer receives or transmits data, and removing or inserting a PIC briefly interrupts
forwarding of traffic through the remaining PICs.
For PIC replacement instructions, see “Replace a PIC” on page 87.
PIC Components
Most PICs supported on the M5 and M10 routers have the following components. For
complete specifications, see the M5 and M10 Internet Routers PIC Guide. For information
about pinouts for PIC cable connectors, see “Cable Connector Pinouts” on page 171.
•
One or more cable connector ports—Accept a network media connector.
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LEDs—Indicate PIC and port status. Most PICs have an LED labeled STATUS on the
PIC faceplate. Some PICs have additional LEDs, often one per port. The meaning of
the LED states differs for various PICs. For more information, see the M5 and M10
Internet Routers PIC Guide.
•
Ejector lever—Controls the locking system that secures the PIC in the card cage.
Flexible PIC Concentrators (FPCs)
Flexible PIC Concentrators (FPCs) house the PICs that connect the router to network media
(for information about PICs, see “Physical Interface Cards (PICs)” on page 9). On the M5 and
M10 routers, each FPC is built in (cannot be removed from the chassis as on other M-series
platforms) and corresponds to a horizontal row of PIC slots. The single FPC on the M5 router
is numbered 0 (zero) and the two FPCs on the M10 router are numbered 0 and 1, top to
bottom. Each FPC accommodates up to four regular PICs or one quad-wide PIC.
Forwarding Engine Board (FEB)
The Forwarding Engine Board (FEB) performs route lookup, filtering, and switching
on incoming data packets, then directs outbound packets to the appropriate FPC for
transmission to the network. It can process 40 million packets per second (Mpps).
The FEB installs into the midplane from the rear of the chassis, as shown in Figure 3. It
weighs approximately 7 lb (3.2 kg). The FEB is field-replaceable, but you must power down
the router before removing it from the chassis. Packet forwarding halts until the FEB is
replaced, the router is powered on, and the Routing Engine finishes booting.
For FEB replacement instructions, see “Replace the FEB” on page 84.
The FEB communicates with the Routing Engine using a dedicated 100-Mbps Fast Ethernet
link that transfers routing table data from the Routing Engine to the forwarding table in the
Internet Processor II ASIC. The link is also used to transfer from the FEB to the Routing
10 M5 and M10 Internet Routers Hardware Guide