"I am not a big fan of carrier-grade network address translation. Part of the reason is the whole notion of network address translation is brittle and it doesn't permit servers to be available on the consumer premises," Vint Cerf, chief Internet evangelist for Google, told Network World in a recent interview. "But it may turn out that NATs are needed in order to facilitate the transition during this period when we have to run both protocols."
LSN contrasts with the ideal solution: to move all devices to using native IPv6 as quickly as reasonably possible -- not tunneled, not translated, but native. That's difficult to do when it's 2011 and customer premises equipment (CPE) and consumer networking gear don't yet properly support IPv6.
Some, such as Cisco's Linksys consumer routers, don't have IPv6 yet at all, although Cisco has promised to add IPv6 to its new routers by mid-2011. (Ironically, Cisco is otherwise ears-deep in the Plugfests, supplying a DHCPv4/DHCPv6 server for the tests.) A Cisco spokesperson confirmed, "Linksys routers being launched this spring will have IPv6 support -- also the E4200 we launched in January will have a firmware upgrade planned for April."
However, Cisco isn't sure yet if routers bought prior to 2011 will get IPv6. "We are currently looking into which 'legacy' Linksys product can support IPv6. (There are many things that influence us being able to do it -- including if there is enough memory, as well as other factors.) The engineer teams are working on that," the spokesperson said.
Network professionals are comfortable with "rooting" their home networking gear and can always wipe out the vendor's firmware and install OpenWRT or DD-WRT. But that's not the kind of task an average consumer can or will do, nor is it a saleable tactic for an ISP to recommend and support.