Christian Vogt wrote:
One thing that IPv6 NAT has in advantage to IPv4 NAT is that it can be
stateless, isomorphic, and port transparent [...]
As I already stated, proper translation of ftp PORT command,
for example, need stateful tracking of ftp command sequences.
Fragmentation reassembly needs another state, because transport
checksum may be located in second fragment.
And, IPv6 NAT can not be transparent to IPSEC.
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