Vpns; Interface Process; Chassis Process; Snmp And Mib Ii Processes - Juniper M10 Hardware Manual

Routing Engine Software Components

VPNs

The JUNOS software supports several types of VPNs:

Interface Process

The JUNOS interface process manages the physical interface devices and logical interfaces
on the router. It implements the JUNOS command-line interface (CLI) commands and
configuration statements that you use to specify interface properties such as location (FPC
location in the FPC card cage 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 interface process communicates with the interface process in the Packet
Forwarding Engine through the JUNOS kernel, enabling the JUNOS Internet software to track
the status and condition of router interfaces.

Chassis Process

The JUNOS chassis process allows you to configure and control the properties of the
router, including conditions that trigger alarms and clock sources. The chassis process
communicates directly with a chassis process in the JUNOS kernel.

SNMP and MIB II Processes

The JUNOS Internet software supports the Simple Network Management Protocol (SNMP),
versions 1, 2, and 3, which provides a mechanism for monitoring the state of the router.
This software is controlled by the JUNOS SNMP and Management Information Base (MIB) II
processes, which consist of an SNMP master agent and a MIB II agent.
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M5 and M10 Internet Routers Hardware Guide
•
Layer 2 VPNs—A Layer 2 VPN links a set of sites sharing common routing information,
and whose connectivity is controlled by a collection of policies. A Layer 2 VPN is not
aware of routes within a customer's network. It simply provides private links between a
customer's sites over the service provider's existing public Internet backbone.
•
Layer 3 VPNs—A Layer 3 VPN links a set of sites that share common routing
information, and whose connectivity is controlled by a collection of policies. A Layer 3
VPN is aware of routes within a customer's network, requiring more configuration on
the part of the service provider than a Layer 2 VPN. The sites that make up a Layer 3
VPN are connected over a service provider's existing public Internet backbone.
•
Interprovider VPNs—An interprovider VPN supplies connectivity between two VPNs
in separate autonomous systems (ASs). This functionality could be used by a VPN
customer with connections to several various ISPs, or different connections to the
same ISP in various geographic regions.
•
Carrier-of-Carrier VPNs—Carrier-of-carrier VPNs allow a VPN service provider to supply
VPN service to a customer who is also a service provider. The latter service provider
supplies Internet or VPN service to an end customer.