[vox-tech] Wireless ethernet trobleshooting.

[Jeff Newmiller]

On Tue, 22 Jan 2002, Rod Roark wrote:

> 
> On Tuesday 22 January 2002 09:24, Jeff Newmiller wrote:
> ...
> > The 169.254.0.0/16 network has been proposed for use in automatic
> > configuration in the absence of a DHCP server. I am not aware if this is
> > an actual sanctioned use, but it apparently has become de-facto use by
> > the presence of implementations such as Microsoft Networking.
> >
> > Ergo, the computer(s) having trouble are probably Windows machines, and
> > are having difficulty contacting the dhcp server.
> > ...
> 
> Remarkable!  You mean the machines when configured as dhcp clients will 
> silently fail when unable to contact a server, assigning themselves a 
> random IP address?

Yes.  If I recall correctly, this network was originally owned by HP... I
don't know how MS and HP were interrelated on this research, but that
network is now owned by IETF.

When I went looking this morning, I found
http://www.isi.edu/~bmanning/dsua.html, which begins with a confusing set
of disclaimers but it does seem to describe how various "private" ip
addresses appear to be arranged.  It is slightly out of date, and the IETF
seems to have bitten the bullet and accepted the situation to some degree.

> Reminds me of IE's "friendly HTTP error messages" option which is selected 
> by default -- what it does is throw away error messages that the server 
> tries to send you.

I don't quite see the similarity, except for the idiot light mentality.

> It's evident that Microsoft assumes everyone using their products is a 
> complete idiot.

Apple used a similar mechanism in their Appletalk protocol, which was
quite popular because it was "easy to use".  Even if your users are not
idiots, relieving them of the necessity of thinking in certain situations
can buy you market share by reducing the "guru" overload.

That is, I am somewhat more bothered by the abuse of network "ownership"
by which this was implemented than by the technique itself.  Once you are
aware that this is how these clients behave, you can get on with the job
at hand.

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