Subject: Re: HEADS UP! Default value of ip6_v6only changed
To: None <>
From: William Allen Simpson <>
List: tech-net
Date: 10/29/2003 07:38:08
Jun-ichiro itojun Hagino wrote:
>         IPV6_V6ONLY and its default value was discussed in a design group for
>         2553bis.  many of the people there wore vendor hat, and they were
>         reluctant of changing the OS behavior, hence they refused to change.
>         some (including me) suggested the default value be "implementation
>         depenedent", but the editor of 2553bis ignored it.
Politically, I'm not surprised.  After all, they made my opponent on 
this issue a member of the IESG some years back.  (Admittedly, I'd 
turned down nominations for various positions on the IESG, on the 
grounds that a not-independently-wealthy consultant cannot afford to 
devote most/all of his time.  Sun is big enough to support an IESG 
member or two, and that's a good thing.)

Anyway, IPV6_V6ONLY=1 obviates ngtrans, his long-term baby. 

>         btw, freebsd changed the value from "off" to "on" between
>         4.x to 5.x to secure itself from the possible vulnerabilities.
>         openbsd does not implement IPv4 mapped address behavior at all.
>         why netbsd has to make the backward change, i.e. secure behavior to
>         insecure behavior?  portable programs cope with the issue already
>         (since MS WinXP is basically "v6only=1").
This I didn't know.  So, why is NetBSD going against the "rough 
consensus and running code"?
William Allen Simpson
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