Chapter 3

JUNOS Internet Software Overview
The JUNOS Internet softwareis especially designed for the large production
networks typically supported by InternetS erviceProviders (ISPs). It incorporates
Internet Protocol (IP)routing software and software for management of interfaces,
networks, and the router chassis.
TheJUNOSInternetsoftwarerunsontheRoutingEngine. Thesoftwareconsistsof
processes that support Internet routingprotocols, control the router’s interfaces
and the router chassis itself, and providean interface for system management.
The processes run on top ofa kernel that coordinates the communication among
processes and has a directlink to the Packet Forwarding Engine software.
Use the JUNOS Internet software to configure the routing protocols that run on
the router and the properties of router interfaces. After you have activated a
software configuration, use the JUNOS Internet software to monitor the protocol
traffic passing through the routerand to troubleshoot protocol and network
connectivity problems.
For additionalinformation about the JUNOS Internet software, including its security
features and a listof the industry standards it supports, see the JUNOS SystemBasics
Configuration Guide. For complete informat ion about configuring the software,
including examples,see the JUNOS Internet software configuration guides.
This chapter discusses thefollowing topics:
Routing Engine SoftwareComponents on page 43
Toolsfor Accessing and Configuring the Software on page 50
Tools forMonitoring the Software on page 50
Software Upgrades on page 50

Routing Engine Software Components

The Routing Engine software consists of several software processes that cont rol
router functions and a kernel thatcoordinates communication among the
processes,as described in the following sections:
Routing ProtocolProcess on page 44
Routing Engine Software Components 43