Biggest mistake for IPv6: It's not backwards compatible, developers admit

[Joe Abley]

On 27-Mar-2009, at 22:21, Erik Kline wrote:

> I think also that the time for retrospection is not yet upon us.   
> The IPv6 transition has recently been gaining steam.

I think it would be great if people could stop talking about the "IPv6  
transition", and in doing so help spread the message that the IPv4  
Internet is not going away any time soon. Common perception is that  
IPv6 is a drop-in replacement for IPv4, hence incredulous news stories  
such as that quoted at the head of this thread. Whatever was imagined  
in the past, this is surely not the current operational reality.

What is required is not for people (service architects, content  
providers, access providers, users) to turn off IPv4 and turn on IPv6,  
but instead to add IPv6 capability *in addition to* IPv4. If IPv6 has  
a future in our lifetimes (and I think it does) it is in an  
overwhelmingly dual-stack world, not a world of v6-only clients.

I think this is an important distinction. Transition implies that  
people should wait "until IPv6 is ready" before "switching". Those  
people will be waiting a long time.


Joe