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


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... preventing these threats and additionally providing integrity, confidentiality, replay protection, and origin protection between tunnel endpoints ...


... IKEv2. For the purposes of this document, where the confidentiality of ESP [RFC4303 ...


... integrity and data origin authentication, confidentiality, and optional (at the discretion of the receiver) anti-replay ...
... receiver) anti-replay features. Using confidentiality without integrity is discouraged. ESP ...
... integrity is discouraged. ESP furthermore provides limited traffic flow confidentiality. IPsec ...



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