Juniper JUNOSE 11.2.X BGP AND MPLS, Руководство по настройке

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Tracking Resources for MPLS Traffic Engineering Overview on page 253
• Topology-Driven LSPs Overview on page 255
• LDP Graceful Restart Overview on page 256
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LDP-IGP Synchronization Overview on page 258
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Use of RSVP-TE Hello Messages to Determine Peer Reachability on page 260
• RSVP-TE Graceful Restart Overview on page 263
• RSVP-TE Hellos Based on Node IDs Overview on page 265
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BFD Protocol and RSVP-TE Overview on page 266
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Tunneling Model for Differentiated Services Overview on page 267
• EXP Bits for Differentiated Services Overview on page 268
• Point-to-Multipoint LSPs Overview on page 271
MPLS Overview
In conventional IP routing, as a packet traverses from one router to the next through a
network, each router analyzes the packet’s header and performs a network layer routing
table lookup to choose the next hop for the packet. In conventional IP forwarding, the
router looks for the address in its forwarding table with the longest match (best match)
for the packet’s destination address. All packets forwarded to this longest match are
considered to be in the same forwarding equivalence class (FEC).
MPLS is a hybrid protocol that integrates network layer routing with label switching to
provide a layer 3 network with traffic management capability. MPLS provides
traffic-engineering capabilities that make effective use of network resources while
maintaining high bandwidth and stability. MPLS enables service providers to provide
their customers with the best service available given the provider’s resources, with or
without traffic engineering. MPLS is the foundation for layer 3 and layer 2 VPNs.
The two basic components of MPLS are label distribution and data mapping.
• Label distribution is the set of actions MPLS performs to establish and maintain a
label-switched path (LSP), also known as an
MPLS tunnel .
•
Data mapping is the process of getting data packets onto an established LSP.
Related Topics MPLS Terms and Acronyms on page 212
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Terminology for MPLS Topics on page 210
Terminology for MPLS Topics
Certain terms used with MPLS, such as the names of messages, are often expressed in
the RFCs and other sources either with initial uppercase letters or all uppercase letters.
For improved readability, those terms are represented in lowercase in this chapter. Table
49 on page 211 lists the terms and some of their variant spellings.
Copyright © 2010, Juniper Networks, Inc. 210
JunosE 11.2.x BGP and MPLS Configuration Guide