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


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... destination port 500 and possibly also port 4500 if NAT traversal is used. The packet format ...


... SPD). The NAT traversal mechanism provided by IKEv2 introduces some weaknesses into IKE ...


... destination port 500 and possibly also port 4500 if NAT traversal is used. The IDci and IDcr payloads ...


... B.2. NAT Traversal and Mobility ...
... endpoints support IPsec NAT traversal extensions, UDP encapsulation ...
... For IPv6-in-IPv4 tunneling, NAT traversal is interesting for two reasons: ...
... tunneling mechanisms. 2. Using NAT traversal allows the outer address to change without having to renegotiate the SAs ...



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