Reduces exposure to IPv6 prefixes
—IPv6 prefixes are
less exposed than if you didn’t translate network prefixes, however,
NPTv6 is not a security measure. The interface identifier portion
of each IPv6 address is not translated; it remains the same on each
side of the firewall and visible to anyone who can see the packet
header. Additionally, the prefixes are not secure; they can be determined
by others.