Vpns; Interface Process; Chassis Process - Juniper TX MATRIX PLUS Hardware Manual

VPNs

Interface Process

Chassis Process

Copyright © 2010, Juniper Networks, Inc.
table. In other words, the terms import and export are used with respect to the routing
table.
Routing policy enables you to control (filter) which routes are imported into the routing
table and which routes are exported from the routing table. Routing policy also allows
you to set the information associated with a route as it is being imported into or exported
from the routing table. Routing policies applied to imported routes control the routes
used to determine active routes, whereas policies applied to exported routes control
which routes a protocol advertises to its neighbors.
You implement routing policy by defining policies. A policy specifies the conditions to
use to match a route and the action to perform on the route when a match occurs. For
example, when a routing table imports routing information from a routing protocol, a
routing policy might modify the route's preference, mark the route with a color to identify
it for later manipulation, or prevent the route from even being installed in a routing table.
When a routing table exports routes to a routing protocol, a policy might assign metric
values, modify the BGP community information, tag the route with additional information,
or prevent the route from being exported altogether. You also can define policies for
redistributing the routes learned from one protocol into another protocol.
The Junos OS supports several types of VPNs:
Layer 2 VPNs.
Layer 3 VPNs.
Interprovider VPNs.
Carrier-of-Carrier VPNs.
The Junos OS interface process manages the physical interface devices and logical
interfaces in the routing matrix. It implements the Junos OS command-line interface
(CLI) commands and configuration statements that you use to specify interface properties
such as location (FPC location in the routing matrix and PIC location on an FPC), the
interface type (such as SONET/SDH or ATM), encapsulation, and interface-specific
properties. You can configure both interfaces that are currently active and interfaces that
might be installed later.
The Junos OS interface process communicates with the Packet Forwarding Engine through
the Junos kernel, enabling the Junos OS to track the status and condition of routing matrix
interfaces.
The Junos OS chassis process, which runs on all Routing Engines in the routing matrix,
allows you to configure and control the properties of the routing matrix, including
conditions that trigger alarms and clock sources. The chassis process running on the
TX Matrix Plus Routing Engine manages the components in the TX Matrix Plus chassis,
and the chassis process running on each T1600 router Routing Engine manages the
Chapter 4: Junos OS in a Routing Matrix Overview
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