Scope of Unique Local IPv6 Unicast Addresses

Document Type Expired Internet-Draft (individual)
Author Fernando Gont 
Last updated 2021-07-09 (latest revision 2021-01-05)
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Unique Local IPv6 Unicast Addresses (ULAs) are formally part of the IPv6 Global Unicast address space. However, the semantics of ULAs clearly contradict the definition of "global scope". This document discusses the why the terminology employed for the specification of ULAs is problematic, along with some practical consequences of the current specification of ULAs. Finally, it formally updates RFC4291 and RFC4193 such that the scope of ULAs is defined as "local".


Fernando Gont (

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