Re: One socket per AF (Was: 6to4 using ::FFFF:0000:0000/96...)

[Antonio Querubin <tony@lava.net>]

On Mon, 28 Jan 2008, Jeroen Massar wrote:

> Yes, IPv4-mapped/compat was a good idea, and using it correctly internally in 
> an application is probably a good move. But using it on the wire or when 
> presenting it to users is definitely not.

If you use one socket per AF, you really wouldn't need mapped addresses 
would you?  And yet you agree that using mapped addresses correctly 
internally is a good thing.  The main motivator for using mapped 
internally is if you program to a single unified socket for both AF.  Or 
am I misunderstanding you?

I agree that mapped/compat on the wire is a bad thing but hasn't that dead 
horse been beaten enough already?

In a v6-only world none of this would matter, but we have a transition we 
need to get through and the way things are looking it's gonna be a very 
long transition.  I think for the majority of apps and their developers, a 
significant paradigm change to two socket programming adds unnecessary 
complexity and is counter-productive to transition efforts.  The benefits 
of unified socket simplicity outweigh the risks to the relatively small 
percentage of apps that actually need to care what type of IP address is 
used.


Antonio Querubin
whois:  AQ7-ARIN