Which functionality is required within an IP router that is situated at the boundary of an IPv4 network and an IPv6 network to allow communication between IPv6- only and lPv4-on|y nodes?
A. Autoconfiguration
B. Automatic 6to4 Tunnel
C. Automatic 6to4 Relay
D. Network Address Translator-Protocol Translator (NAT-PT)
E. lntrasite Automatic Tunnel Address Protocol (ISATAP)
D
https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipaddr_nat/configuration/15-mt/nat-15-mt-book/ip6-natpt.html
NAT-PT Overview
Network Address Translation (NAT)-Port Translation (PT) for Cisco software based on RFC 2766 and RFC 2765 is a migration tool that helps customers transition their IPv4 networks to IPv6 networks. Using a protocol translator between IPv6 and IPv4 allows direct communication between hosts that use different network protocols.