Re: Location independence?

Gregory J. Woodhouse (gjw@wnetc.com)
Wed, 26 Feb 1997 07:23:02 -0800 (PST)


Date: Wed, 26 Feb 1997 07:23:02 -0800 (PST)
From: "Gregory J. Woodhouse" <gjw@wnetc.com>
To: Daniel LaLiberte <liberte@ncsa.uiuc.edu>
Cc: touch@isi.edu, uri@bunyip.com
Subject: Re:  Location independence?
In-Reply-To: <199702260811.CAA15512@void.ncsa.uiuc.edu>
Message-Id: <Pine.SGI.3.95.970226070956.27000E-100000@shellx.best.com>

On Wed, 26 Feb 1997, Daniel LaLiberte wrote:

> touch@isi.edu writes:
>  > IP numbers are not looked up. That's the point.
>  > That's why they're "locations", rather than "names".
> 
> IP numbers are looked up in router tables.
> 
> Curiously, many people associate looking something up with it being a
> location rather than a name.  The thing you look up is *located* in a
> table or data structure of some kind.
>

Actually, I think the point is that IP addresses represent topology
specific information. True enough, they don't represent physical addresses.
To illustrate, when I dial in to my ISP from home I always use the same IP
address regardless sof the local access number I choose, and at work my IP
address is assigned by DHCP, even though my Ethernet card is the same every
time. So, in this sense IP addresses could be said to be names and not
locations. But, on the other hand, an IP address is network specific: I
don't have the option of interchanging the IP addresses I use at home and
at work, so in this sense, it is reasonable to think of IP addressses as
locations rather than names.
 

Resource names, such as URNs should not be bound to any particular network
configuration. If I have a  web page on my home computer, or on my ISP
hosted web site, I ought to be able to move it to another web site (even
one a totlly different network or AS) without changing its name. IP
addresses do not have this property.

---
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