Juniper JUNOSE 11.2.X BGP AND MPLS, Configuration Manual

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An MPLS in label that is matched against the outermost label of the received MPLS
packet.
• The MPLS next hop, which specifies the actions to be performed on the MPLS packet.
MPLS next hops can be chained together to create complex actions.
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A spoof check field that specifies the type of spoof checking is performed to determine
whether the MPLS packet arrived from a legitimate source. See “MPLS Packet Spoof
Checking Overview” on page 234 for more information.
Related Topics See Monitoring MPLS on page 321, for information about enabling statistics collection
for MPLS forwarding table entries.
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MPLS Label Distribution Methodology on page 227
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MPLS Label Switching and Packet Forwarding Overview on page 218
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MPLS Forwarding and Next-Hop Tables Overview on page 233
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MPLS Packet Spoof Checking Overview on page 234
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IP and IPv6 Tunnel Routing Tables and MPLS Tunnels Overview on page 234
MPLS Packet Spoof Checking Overview
The MPLS forwarding table enables MPLS to determine whether an MPLS packet received
from an upstream neighbor contains an MPLS label that was advertised to that neighbor.
If not, the packet is dropped. Each entry in the forwarding table has a spoof check field
that specifies the type of checking that must be performed for the associated in label.
The signaling protocol (BGP, LDP, or RSVP) that populates the entry in the MPLS
forwarding table sets the spoof check field.
MPLS supports the following types of spoof checking:
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Router spoof checking—MPLS packets are accepted only if they arrive on an MPLS
major interface that is in the same virtual router as the MPLS forwarding table.
• Interface spoof checking—MPLS packets are accepted only if they arrive on the
particular MPLS major interface identified in the spoof check field.
You can use the show mpls forwarding command to view the spoof check field for an
MPLS forwarding table entry.
Related Topics MPLS Forwarding and Next-Hop Tables Overview on page 233
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IP and IPv6 Tunnel Routing Tables and MPLS Tunnels Overview
The IP and IPv6 tunnel routing tables contain routes that point only to tunnels, such as
MPLS tunnels. The tunnel routing table is not used for forwarding. Instead, protocols
resolve MPLS next hops by looking up the routes in the table. For example, BGP uses the
table to resolve indirect next hops for labeled routes.
Copyright © 2010, Juniper Networks, Inc. 234
JunosE 11.2.x BGP and MPLS Configuration Guide