RFC 4291:IP Version 6 Addressing Architecture
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requirement


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... link, the implementation needs to create a local-scope interface identifier. The only requirement is that it be unique within a subnet prefix. There are many possible approaches to select a ...
... This document purposely continues the use of 0xFF and 0xFE because it meets the requirements for IPv6 interface identifiers (i.e., that they must be unique on the link), IEEE ...



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