Subject: Re: name service (does anyone else see this?)
To: John Hawkinson <>
From: John F. Woods <>
List: current-users
Date: 08/06/1995 21:36:39
> > > You should certainly use the loopback address in preference to
> > >, which is entirely bogus. If any implementation accepts it,
> > > it's confused itself.
> > Since most TCP/IP implementations do accept as the local host,
> > and this is a very well known feature, there's no problem with using it
> > where it works.
> This is misleading.

A quick check of RFC 1700 (Assigned Numbers) confirms this; address {0, 0}
means "this host" only when used as a *source* address, and should not be
used as a destination address.  I don't know what the history of {127, any}
is for the loopback address, but it's been official since 11/86 (RFC 990;
it was "reserved" in the version before that, RFC 900).

If there's a right way and a wrong way to go about it, it seems to me that
insisting on using the wrong way because it "works" (now, anyway) is, well,

(The implementation that let it leak out to the nearest router (an old Sun?)
is even more wrong than one which accepts it as a destination address meaning
"this host".)