Hardware Overview

The JUNOS software runs on two types of Juniper Networks routers: M- and T-series routers. The routers consist of the following major hardware components:

• Sheet metal of the chassis.
• Power supplies (AC or DC).
• Impeller trays.
• Fan assemblies.
• Routing Engine.
• System Control Board (SCB), System and Switch Board (SSB), Switching and Forwarding Module (SFM), Switch Interface Board (SIB), or Forwarding Engine Board (FEB).
• Flexible PIC Concentrators (FPCs), each populated by up to four Physical Interface Cards (PICs) for various interface types, including SONET/SDH OC-192, OC-48, OC-12, and OC-3, ATM OC-12 and OC-3, DS3 (T3), E3, DS1 (T1), E1, Gigabit Ethernet, Fast Ethernet, and Channelized OC-12. Some PICs do not require an FPC.