Chapter 2
MPLS Overview
This chapter describes Multiprotocol Label Switching (MPLS) and contains the following
sections:
â– MPLS Overview on page 202
â– Conventions for MPLS Topics on page 202
â– MPLS Terms and Acronyms on page 203
â– MPLS Features on page 206
â– MPLS Platform Considerations on page 207
â– MPLS References on page 207
â– MPLS Label Switching and Packet Forwarding on page 209
â– MPLS Label Distribution Methodology on page 218
â– Mapping IP Data Packets onto MPLS LSPs on page 220
â– Statistics for IP Packets Moving On or Off MPLS LSPs on page 222
â– MPLS Forwarding and Next-Hop Tables on page 224
â– Spoof Checking MPLS Packets on page 225
â– IP and IPv6 Tunnel Routing Tables and MPLS Tunnels on page 225
â– Explicit Routing for MPLS on page 226
â– MPLS Interfaces and Interface Stacking on page 227
â– MPLS Label Distribution Protocols on page 229
â– ECMP Labels for MPLS on page 233
â– MPLS Connectivity Verification and Troubleshooting Methods on page 235
â– Point-to-Multipoint LSPs Connectivity Verification at Egress Nodes
Overview on page 237
â– Ping Extensions for Point-to-Multipoint LSPs Connectivity Verification at Egress
Nodes on page 237
â– TLVs and Sub-TLVs Supported for Point-to-Multipoint LSPs Connectivity
Verification at Egress Nodes on page 239
â– LDP Discovery Mechanisms on page 242
â– MPLS Traffic Engineering on page 243
â– Topology-Driven LSPs on page 246
â– LDP Graceful Restart on page 247
â– 201