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                                          Special-Purpose Multiprotocol Label Switching (MPLS) Label Values

Created
        2002-11-08

Last Updated
        2026-06-30

Available Formats
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Registries Included Below

  • Base Special-Purpose MPLS Label Values
  • Extended Special-Purpose MPLS Label Values

Base Special-Purpose MPLS Label Values

Registration Procedure(s)

             Standards Action


Reference
        [RFC 3032][RFC 7274][RFC 9017]

Available Formats
        [IMG]
        CSV

Value           Description                  Reference
  0   IPv4 Explicit NULL Label         [RFC 3032]
  1   Router Alert Label               [RFC 3032]
  2   IPv6 Explicit NULL Label         [RFC 3032]
  3   Implicit NULL Label              [RFC 3032]
  4   MPLS Network Actions             [RFC 9994]
 5-6  Unassigned
  7   Entropy Label Indicator (ELI)    [RFC 6790]
8-12  Unassigned
 13   Generic Associated Channel Label [RFC 5586]
 14   OAM Alert Label                  [RFC 3429]
 15   Extension Label (XL)             [RFC 7274]; [RFC 9017]

Extended Special-Purpose MPLS Label Values

Registration Procedure(s)

             Standards Action


Reference
        [RFC 7274]

Available Formats
        [IMG]
        CSV

   Value                                                        Description                                                     Reference
   0-15     Reserved. Never to be made available for allocation.                                                                [RFC 7274]
    16      Metadata Label Indicator (MLI)                                                                                      [RFC 8595]
    17      Metadata Present Indicator (MPI)                                                                                    [RFC 8595]
    18      Flow-ID Label Indicator (FLI)                                                                                       [RFC 9714]
  19-239    Unassigned
  240-255   Reserved for Experimental Use                                                                                       [RFC 7274]
256-1048575 Reserved. Not to be made available for allocation without a new Standards Track RFC to define an allocation policy. [RFC 7274]

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