Juniper JUNOSE 11.2.X IP SERVICES, Configuration Manual

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•
Rejecting some routes
• Determining the routing protocol used to distribute the routes
You can think of routing policy as a way to control the flow of routes into and out of the
router.
The decision about which routes to accept from and advertise to various neighbors has
an important impact on the traffic that crosses a network. Routing policy is used to
enforce business agreements between two or more Internet service providers (ISPs)
concerning the amount and type of traffic that is allowed to pass between them.
You can use one or more of the following mechanisms to configure routing policy:
•
“Route Maps” on page 4
•
“Match Policy Lists” on page 19
• “Access Lists” on page 20
• “Prefix Lists” on page 32
•
“Prefix Trees” on page 35
•
“Community Lists” on page 37
Platform Considerations
Configuring routing policies is supported on all E Series routers.
For information about the modules supported on E Series routers:
• See the ERX Module Guide for modules supported on ERX7xx models, ERX14xx models,
and the Juniper Networks ERX310 Broadband Services Router.
•
See the E120 and E320 Module Guide for modules supported on the Juniper Networks
E120 and E320 Broadband Services Routers.
References
For more information about the protocols discussed in this chapter, see their respective
chapters in this guide and other guides within the JunosE documentation set, and to the
References sections within those chapters.
Route Maps
You can use route maps to control and modify routing information and to define conditions
for redistributing routes between routing domains. You can apply route maps to inbound,
outbound, or redistribution routes. A route map consists of
match clauses and set clauses.
Match clauses specify the attribute values that determine whether a route matches the
route map. A route that has the same attribute values passes the match condition. Routes
that pass all the match conditions match the route map. You issue
match commands
to define the match conditions for a route map. You can specify the match conditions in
Copyright © 2010, Juniper Networks, Inc. 4
JunosE 11.2.x IP Services Configuration Guide