Juniper Networks M160 manual Midplane

M160 Internet Router Hardware Guide

an entire FPC slot in the chassis and insert directly into the slot rather than into an FPC card carrier.)

Flexible PIC Concentrator (FPC)—Processes incoming and outgoing packets.

Up to eight FPCs plug into the midplane from the front of the chassis. Each

FPC accommodates up to four PICs.

Packet Forwarding Engine Clock Generator (PCG)—Sends clock signals to the other Packet Forwarding Engine components. Two PCGs plug into the midplane from the rear of the chassis.

Switching and Forwarding Module (SFM)—Performs route lookup, filtering, and switching. Up to four SFMs plug into the midplane from the rear of the chassis.

For information about Packet Forwarding Engine components, see the following sections:

Midplane on page 12

Physical Interface Cards (PICs) on page 13

Flexible PIC Concentrators (FPCs) on page 14

Packet Forwarding Engine Clock Generators (PCGs) on page 18

Switching and Forwarding Module (SFM) on page 19

Midplane

The midplane is a panel located in the center of the chassis, running from side to side and forming the rear of the FPC card cage (see Figure 4). All router components other than PICs plug directly into the midplane. The midplane contains an EEPROM that stores the serial number and revision level of the midplane.

The midplane performs the following functions:

Transfer of packets—The midplane accepts an incoming packet after it is processed by an FPC, and transmits it to an SFM. The SFM performs switching and forwarding functions and transfers outgoing packets back across the midplane to the FPCs for transmission to the network.

Power distribution—The midplane distributes power to all router components from the power supplies attached to it.

Signal connectivity—The midplane transports the signals exchanged by system components for monitoring and control purposes.

12 Packet Forwarding Engine