MPLS Overview
Multiprotocol Label Switching (MPLS) on the vRouter provides the data plane support and the basic Label Distribution Protocol (LDP) and Resource Reservation Protocol for Traffic Engineering (RSVP-TE) support that serves as a foundation on which to build additional features.
- Basic MPLS forwarding
- LDP
- RSVP-TE
Basic MPLS forwarding support
The following basic MPLS forwarding features are supported:
- Label Switched Paths (LSPs) using IPv4 next hops
- Imposition of labels onto IPv4 packets
- Routes with de-aggregate to global tables
- ECMP for imposition and labeled routes
- IP fragmentation
- IP traceroute using LSPs (when TTL propagation is enabled)
- Generation of too-big ICMP (when the MTU is exceeded with the DF bit set)
- Configurable TTL propagation
- Configurable label table size
- Per-interface packet statistics
LDP support
The following LDP features are supported:
- Label allocation and advertisement control
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Outbound filtering
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Allocation control; only label ranges supported
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- Null label allocation
- Explicit null if configured; implicit null if not configured
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Session authentication
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IGP synchronization
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Downstream-on-demand advertisement mode
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IPv4 LSPs
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ECMP for imposition and labeled routes
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Graceful restart helper
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Operation in default VRF only
RSVP-TE support
The following RSVP features are supported:
- CSPF OSPF computation (resource utilization)
- Explicit path (loose and strict)
- Fast reroute with one-to-one protection
- IGP shortcut (IGP routes through a tunnel)
- IPv4 point-to-point tunnels
- Node and link protection
- Path affinities
- Reoptimization
- Record route
- Refresh reduction (scalability)
- Shared explicit filter
- Tail end implicit or explicit null signaling
- RSVP operation in default VRF only
- Graceful restart
- Tunnels to destinations outside the OSPF area
Not yet supported
- L3VPN
- Diffserv-aware TE
- Facility backup
- MPLS QoS
- Point-to-multipoint tunnels
- Shared Risk Link Groups (SRLG)