Chapter 1

System Overview
This chapter providesan overview of the Juniper Networks M160 Internet router,
discussing the following topics:
System Description on page3
Field-Replaceable Units (FRUs) on page 4
System Redundancy on pag e 4
Safety Requirements,Warnings, and Guidelines on page 5

System Description

The M160 Internet router is a complete routingsystem that provides
SONET/SDH, ATM,Ethernet, and channelized interfaces for large networks
and network applications, such as thosesupported by Internet service
providers (ISPs). Application-specific integrated circuit s (ASICs), a definitive
part of the router design, enable the router to forward data at the high
speeds demanded by current networkmedia.
The router accommodates up toeight Flexible PIC Concentrators (FPCs), which can
each be configuredwith a variety of network media types, altogetherproviding up to
32 OC-12/STM-4, 32 OC-48/STM-16, or eight OC-192/STM-64 port s per system. The
router height of 35 in. (89 cm) enables stackedinstallation of two M160 systems in
a single floor-to-ceiling rack, for increased port densi typ er unit of floor space.
The router’s maximum aggregate throughputis 160 gigabits per second (Gbps)
simplex or 80 Gbps full duplex. The router provides very high throughpu t for
any combination of Physical InterfaceCards (PICs) that does not exceed 3
Gbps on an FPC1 or 10 Gbps on an FPC2. A combination that exceeds these
numbers is supported, but constitutes oversubscription.
The router architecturecleanly separates control operations from packetforwarding
operations, which helps to eliminate processing and traffic bottlenecks. Control
operations in the router areperformed by the Routing Engine, which runs
JUNOS Internet software tohandle routing protocols, traffic engineering, policy,
policing, monitoring, and configurationmanagement. Forwarding operations
in the router are performed bythe Packet Forwarding Engine, which consists
of hardware, including ASICs, designed by Juniper Networks.
System Description 3