DS-Lite availability: The DS-Lite technology is favored by Comcast, which has already started field trials of various IPv6 solutions. Comcast needs to deploy IPv6 in its access network anyway to manage DOCSIS 2.0/3.0 cable modems The AFTR solution by A10 Networks was tested by Comcast. ISC has developed an open-source AFTR solution in concert with Comcast.
IPv4 to IPv6 translation solutions: The A+P proposal
All NAT solutions rely on a simple fact: More than 65,000 TCP and UDP sessions can be created from a single IP address, but a typical IP host rarely uses more than a few hundred of them. Traditional NAT devices dynamically allocate TCP and UDP port numbers belonging to the same pool of public IP addresses for outgoing TCP or UDP sessions coming from numerous private IP addresses. The A+P proposal changes the rules and assigns static ranges of TCP/UDP ports to residential Internet users. As in today's internet, the CPE device performs the NAT function, giving the power users more control over NAT and TCP/UDP port allocation. Similar to DS-Lite, IPv6 is used as the transport between CPE devices and AFTR.
A+P availability: A+P has no running implementation at this moment.
NAT64: The only workable IPv4 to IPv6 translation solution
This is the only solution encouraging unconditional migration to IPv6 (all the others can prolong the IPv4 pains indefinitely or even avoid end-user migration to IPv6). NAT64 takes the good parts of NAT-PT and enables IPv6-only clients to access IPv4-only servers. It also solves several glitches of NAT-PT and makes the NAT functionality more predictable and aligned with the modern understanding of NAT requirements as specified by the BEHAVE IETF working group.
