Routing Engine Functions; Figure 24: Routing Engine Architecture - Juniper Internet Router M160 Hardware Manual

M160 Internet Router Hardware Guide

Figure 24: Routing Engine Architecture

JUNOS
software

Routing Engine Functions

The Routing Engine handles all routing protocol processes, as well as
the software processes that control the router's interfaces, the chassis
components, system management, and user access to the router. These
routing and software processes run on top of a kernel that interacts with the
Packet Forwarding Engine. For more information about the processes, see
Routing Engine Software Components on page 43.
The Routing Engine includes the following functions and features:
54
Routing Engine Architecture
System Routing
management protocols
processes
Kernel
Intel-based PCI platform
Processing of routing protocol packets—The Routing Engine handles all
packets that concern routing protocols, freeing the Packet Forwarding Engine
to handle only packets that represent Internet traffic.
Software modularity—Because each software process is devoted to a different
function and uses a separate process space, the failure of one process has little
or no effect on the others.
In-depth Internet functionality—Each routing protocol is implemented with a
complete set of Internet features and provides full flexibility for advertising,
filtering, and modifying routes. Routing policies are set according to route
parameters (for example, prefix, prefix lengths, and Border Gateway Protocol
[BGP] attributes).
Scalability—The JUNOS routing tables have been designed to hold all the
routes in current networks with ample capacity for expansion. Additionally, the
Control
functions
System processes
Operating system