The router supports a number of features that allow
the service provider to control the exchange of routing information
between virtual routers in the router, between routers in the network,
and between protocols within a router:
Access lists—Provide filters that can be applied
to route maps or distribution lists. They allow policies to be created,
such as a policy to prevent forwarding of specified routes between
the BGP-4 and IS-IS routing tables.
Route maps—Modify the characteristics of a route
(generally to set its metric or to specify additional attributes)
as it is transmitted or accepted by a router. Route maps can use access
lists to identify the set of routes to modify.
Distribution lists—Control the routing information
that is accepted or transmitted to peer routers. Distribution lists
always use access lists to identify routes for distribution. For example,
distribution lists could use access lists to specify routes to advertise.
Redistribute routes—Allow routes to be shared
between routing protocols and routing domains. For example, a subset
of BGP-4 routes could be leaked into the IS-IS routing tables.
See JUNOSe IP Services Configuration Guide, for details.
