Re: dual stack & IPv6 on by default

["Steven M. Bellovin" <smb@research.att.com>]

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In message <Pine.LNX.4.44.0303110805510.397-100000@netcore.fi>, Pekka Savola wr
ites:
>On Mon, 10 Mar 2003, Alain Durand wrote:
>> >For edification.  I have a node on a work LAN that knows nothing of IPv6.  
>I
>> >download software and configure my node to be capable of IPv6. I manually
>> >configure my interface to support IPv6.  I now ftp to an IPv6 address.  Thi
>s
>> >is not going to work.  But I was stupid to think it would?  Is this the kin
>d
>> >of basic mistake your also worried about?
>> >
>> Alternate scenario:
>> We ship our system so they configure IPv6 ON by default on all interface.
>> User install this machine on his v4-only network and now experiment
>> larger than usual delays to connect to his favorite servers.
>> User call customer support.
>> This is what I worried about.
>
>How do the delays get longer, I wonder?
>
>Different flavors of BSD have shipped v6-enabled by default since, about
>2000 or 2001, I don't remember anymore, and I've never seen anyone
>complain about increased delays.
>
>I don't think there should be any significant potential drawback *until*
>the system is configured with a non-link-local address.

There have been reports of problems with some Web browsers trying to 
use only the v6 address.


		--Steve Bellovin, http://www.research.att.com/~smb (me)
		http://www.wilyhacker.com (2nd edition of "Firewalls" book)