[[https://www.cisco.com/c/en/us/products/collateral/ios-nx-os-software/enterprise-ipv6-solution/white_paper_c11-676278.html|Cisco Enterprise IPv6 Whitepaper]]\\ 

Dual-Stack Network
  * IPv4 and IPv6 operate at the same time over a common or disparate link/s.
  * Considered a transition technology because it is not meant to be in operation forever. It is meant as a band-aid while IPv4 is depreciated from the network.
  * All devices must support IPv6, otherwise, dual-stack will not work.
  * Software and hardware upgrades may be required as well a network redesign (partial or full) in order to deploy IPv6 everywhere.

Tunneling
  * Can either encapsulate IPv4 packets within IPv6 or IPv6 packets within IPv4 in order to provide connectivity.
  * RFC 6144
  * Dual-stack hosts are needed or interoperability.
  * Users of the new architecture cannot use the services of the underlying infrastructure.

Translation
  * aka AFT (Address Family Translation)
  * Manages communication between IPv6-only and IPv4-only hosts and networks using IP header and address translation between the two address families.
  * Provides a gradual migration to IPv6.
  * Provides business continuity to IPv4 users.
  * ALG (Application-layer Gateway) provides support for translation to specific protocols, such as FTP and SIP which embed IP address information within the payload.

NAT64
  * Facilitates communication between IPv6 and IPv4 only hosts/networks.
  * DNS64 and NAT64 functions are separated.

AFT using NAT64 technology can be achieved by either stateless or stateful means
  * Stateless (RFC 6145) NAT64 is a translation mechanism for algorithmically mapping IPv6 addresses to IPv4 addresses and vice-versa. Doesn't maintain any bindings or session state while performing translation for either IPv4 or IPv6 initiated communications.
  * Stateful (RFC 6146) NAT64 transition IPv6 addresses to IPv4 addresses, and vice-versa. NAT64 creates or modifies bindings or session state while performing translation. Uses static or manual bindings
  * Comparison between stateless and stateful NAT64

||**Stateless NAT64**|**Stateful NAT64**||
||1:1 translation, hence applicable for a limited number of endpoints|1:N translation, hence no constraint on the number of end points therefore, also applicable for carrier grade NAT (CGN)||
||No conservation of IPv4 address|Conserves IPv4 address||
||Helps ensure end-to-end address transparency and scalability|Uses address overloading; hence lacks end-to-end address transparency||
||No state or bindings created on the translation|State or bindings created on every unique translation||
||Requires IPv4-translatable IPv4 address assignment (mandatory requirement)|No requirement for the characteristics of IPv6 address assignment||
||Requires either manual or DHCPv6-based address assignment for IPv6 hosts|Capability to choose any mode of IPv6 address assignment: manual, DHCPv6, or stateless address autoconfiguration (SLAAC)||
  * NAT64 is preferred choice for AFT