Policy-Based Routing Overview - Juniper NETWORK AND SECURITY MANAGER 2010.4 - CONFIGURING SCREENOS DEVICES GUIDE REV 01 Manual

Related
Documentation

Policy-Based Routing Overview

Related
Documentation
Copyright © 2010, Juniper Networks, Inc.
Multicast Route Overview on page 337
Multicast Routing Table Entries Overview on page 346
Multicast Routing Table Preferences Overview on page 346
IRDP Support Overview on page 348
Example: Configuring Multicast Static Routes (NSM Procedure) on page 347
Example: Configuring ICMP Router Discovery Protocol (NSM Procedure) on page 349
Policy-based routing (PBR) provides a flexible mechanism for forwarding data packets
based on polices configured by a network administrator. PBR enables you to implement
policies that selectively cause packets to take different paths. PBR provides a routing
mechanism for networks that rely on Application Layer support, such as antivirus (AV),
deep inspection (DI), or antispam, Web filtering, and/or that require an automatic way
to specific applications.
When a packet enters the security device, ScreenOS checks for PBR as the first part of
the route-lookup process, and the PBR check is transparent to all non-PBR traffic. PBR
is enabled at the interface level and configured within a virtual router context; but you
can choose to bind PBR policies to an interface, a zone, a virtual router (VR), or a
combination of interface, zone, or VRs.
You use the following three building blocks to create a PBR policy:
Extended access lists—Extended access-lists list the match criteria you define for PBR
policies.
Match groups—Match groups provide a way to organize (by group, name and priority)
extended access lists.
Action groups—Action groups specify the route that you want a packet to take. You
specify the" action" for the route by defining the next interface, the next-hop, or both.
NOTE: For details on configuring policy-based routing and route lookup,
see the Concepts & Examples ScreenOS Reference Guide.
Configuring Virtual Routers Overview on page 294
Virtual Router General Properties Overview on page 297
Access List Overview on page 298
Route Maps Overview on page 300
IRDP Support Overview on page 348
Example: Configuring Access Lists (NSM Procedure) on page 299
Example: Configuring Policy-Based Routing (NSM Procedure) on page 352
Chapter 10: Routing
351