RFC 4891:Using IPsec to Secure IPv6-in-IPv4 Tunnel...
RFC-Ref

Security Architecture for the Internet Protocol


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... Kent, S. and R. Atkinson, "Security Architecture for the Internet Protocol", RFC 2401(-> 4301prop), November 1998. ...
... Kent, S. and K. Seo, "Security Architecture for the Internet Protocol", RFC 4301prop, December 2005. ...



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