Packet Forwarding Engine

The Packet Forwarding Engine provides Layer 2 and Layer 3 packet switching, route lookups, packet forwarding, and route lookup functions. Table 28 lists the Packet Forwarding Engine forwarding rate and aggregate throughput for each routing platform.

Table 28: Packet Forwarding Engine Forwarding Rate and Aggregate Throughput Characteristics Per Routing Platform

Specifications	M5/ M10	M7i	M10i	M20	M40	M40e	M160	M320	T320	T640
Packet forwarding rate in million packets per second (Mpps)	40	16	16	40	40	40	160	385	385	770
Aggregate throughput in gigabits per second (Gbps)	6.4	8.4	12.8	25.6	40	51.2	160	320	320	640

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	M5/ M10	M7i	M10i	M20	M40	M40e	M160	M320	T320	T640
Midplane	X	X	X	X	X	X	X	X
PIC	X	X	X	X	X	X	X	X	X	X
FPC	Built-in			X	X	X	X	X	X	X
FIC		X
CFEB		X	X
FEB	X
SSB				X
SCB					X
SFM						X	X
Layer 2/Layer 3 Packet Processing ASIC									X	X
Queuing and Memory Interface ASICs								X	X	X
T-series Internet Processor								X	X	X
Switch Interface ASICs								X	X	X
Media-specific ASICs on the PICs	X	X	X	X	X	X	X	X	X	X