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6. IS-IS Flexible Algorithm Include-Any Reverse Admin Group Sub-TLV

This section preserves the RFC text for IGP Flex-Algorithm reverse affinity constraints, including FAERAG, FAD, IS-IS and OSPF Sub-TLVs, reverse Administrative Groups, IANA registrations, and path pruning rules.

Original RFC Text​

6.  IS-IS Flexible Algorithm Include-Any Reverse Admin Group Sub-TLV

   The IS-IS Flexible Algorithm Include-Any Reverse Admin Group Sub-TLV
   is used to advertise the include-any rule that is used during the
   Flex-Algorithm path calculation as specified in Section 11.

   The format of the IS-IS Flexible Algorithm Include-Any Reverse Admin
   Group Sub-TLV is identical to the format of the FAERAG Sub-TLV in
   Section 5.

   IANA has assigned Type value of 11 for the IS-IS Flexible Algorithm
   Include-Any Reverse Admin Group Sub-TLV.

   The IS-IS Flexible Algorithm Include-Any Reverse Admin Group Sub-TLV
   MUST NOT appear more than once in a single IS-IS FAD Sub-TLV.  If it
   appears more than once, the IS-IS FAD Sub-TLV MUST be ignored by the
   receiver.

   The IS-IS Flexible Algorithm Include-Any Reverse Admin Group Sub-TLV
   MUST NOT appear more than once in the set of FAD Sub-TLVs for a given
   Flex-Algorithm from a given IS.  If it appears more than once in such
   set, the IS-IS Flexible Algorithm Include-Any Reverse Admin Group
   Sub-TLV in the first occurrence in the lowest-numbered LSP from a
   given IS MUST be used and any other occurrences MUST be ignored by
   the receiver.
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