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Re: Thinking differently about the site local problem (was: RE: site local addresses (was Re: Fw: Welcome to the InterNAT...))

Keith Moore <moore@cs.utk.edu> Mon, 31 March 2003 22:01 UTC

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Date: Mon, 31 Mar 2003 16:56:17 -0500
From: Keith Moore <moore@cs.utk.edu>
To: Jeroen Massar <jeroen@unfix.org>
Cc: moore@cs.utk.edu, huitema@windows.microsoft.com, ietf@ietf.org
Subject: Re: Thinking differently about the site local problem (was: RE: site local addresses (was Re: Fw: Welcome to the InterNAT...))
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> > > Indeed, correctly coded applications will use a getaddrinfo()
> > > and then a connect() in a loop until succesful. 
> > 
> > it's perfectly reasonable to connect to an address without first
> > doing a DNS lookup.
> 
> I think nobody can't help you if you are using hardcoded IP's.
> The only case you have an IP without DNS is when you get it
> passed from another layer/entity (eg in a FTP from the server).

uh, no.   you can get IP addresses from any number of sources other than
DNS, including from other processes that exist on other nodes.  It's a
perfectly reasonable thing to do.

> Can you identify those so that getaddrinfo() can be expanded
> to fix these cases?

getaddrinfo() cannot be fixed.  it's major premise - that the host has
the knowledge to make decisions about which of several addresses is best
to use - is fundamentally flawed, except in a few corner cases.

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