Data Flow Through The Router Packet Forwarding Engine - Juniper JUNOS - NETWORK OPERATION GUIDE REV1 Network Operation Manual

For M-series routers, the Packet Forwarding Engine is implemented in ASICs that
are located on the System Control Board (SCB): a Forwarding Engine Board (FEB)
(M5/M10 router), System and Switch Board (SSB) (M20 router), SCB (M40 router), or
Switching and Forwarding Module (SFM) (M40e and M160 routers). It uses a
centralized route lookup engine and shared memory. For T-series routers, the Packet
Forwarding Engine is implemented in ASICs that are physically located on the
Flexible PIC Concentrator (FPCs) and Physical Interface Card (PICs).
Table 29 lists the Packet Forwarding Engine components for each routing platform.
Table 29: Router Packet Forwarding Engine Components Per Routing Platform
Component
Midplane
PIC
FPC
FIC
CFEB
FEB
SSB
SCB
SFM
Layer 2/Layer 3 Packet Processing ASIC
Queuing and Memory Interface ASICs
T-series Internet Processor
Switch Interface ASICs
Media-specific ASICs on the PICs

Data Flow Through the Router Packet Forwarding Engine

This section describes the sequence in which data flows through each router Packet
Forwarding Engine.
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M5/
M10 M7i M10i
X X X
X X X
Built-in
X
X X
X
X X X
Data Flow Through the M5 and M10 Router Packet Forwarding Engine on
page 94
Data Flow Through the M7i Router Packet Forwarding Engine on page 95
Data Flow Through the M10i Router Packet Forwarding Engine on page 96
Data Flow Through the M20 Router Packet Forwarding Engine on page 97
Data Flow Through the M40 Router Packet Forwarding Engine on page 98
Data Flow Through the M40e Router Packet Forwarding Engine on page 99
Data Flow Through the M160 Router Packet Forwarding Engine on page 100
Chapter 12: Monitoring Key Router Components
M20 M40 M40e M160 M320 T320 T640
X X X X
X X X X
X X X X
X
X
X X
X X X X
Understanding Key Router Components
X
X X X
X X X
X X
X X X
X X X
X X X
X X X
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