🚀 go-pugleaf

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From: REM@Mit-Mc.ARPA (Robert Elton Maas)
Sender: ka@hou3c.UUCP (Kenneth Almquist)
It has been suggested that the IFIP proposal would permit heirarchial
domains of naming authority, but I fail to see it. Could somebody
explain it to me?
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I wonder which version of the IFIP proposal you are looking at.
The latest one I have is "A User-friendly Naming Convention for
Public data Networks", Version 2, November 183, arising from
the IFIP WG6.5 NASE Subgroup meeting, Ottawa, July 1983.

The need is seen for the naming process to be 'user friendly'; that is
it should not depend on knowledge of things which humans are unlikely
to know routinely.  Perhaps an important source of confusion would be
to not distinguish between "names" and "addresses".  Names are to be
expressed in terms of things people can remember easily. Addresses
on the other hand are 'machine-oriented'.

The systems for identifying people in practically all current message
systems, including the ARPAnet 'internet' style, are what would be
called 'machine oriented' in this context.  The domain names and host
names appearing in addresses are closely tied to the hardware config-
urations of the networks.

It is anticipated that one of the purposes of the directories to be
provided in future will be translating from 'names' to 'addresses'.
As an example, my university has several machines with mail boxes
and mail software; this is not unusual.  My address would identify
inter alia which machine *my* mail box is on, and which network(s)
it can be reached by.  My *name* however, would be something like
   (Canada, University of Western Ontario, Julian Davies)
as a fairly minimal version, or I could be named by a more elaborate
specification which also mentioned the Province, my department,
and maybe a nickname or telephone number to be sure of avoiding
ambiguity.

The structure of *names* is defined, now, by a directed labelled
graph structure.  However, the structure is not arbitrary, and the
First Guideline is:
  The dominant structure of the Graph should be hierarchical.

That is, the graph will be 'almost' a tree.  A tree would be a perfect
hierarchy, but here we allow for some flexibility, that in some cases
a person may be reachable via several different routes through the
directory structure.  For instance, it may be that multi-nationals
such as IBM would be represented at the top level of the hierarchy,
and someone in IBM Bulgaria (for instance) could be reached either
starting with the Bulgaria National directory database, or with
the IBM top-level database, in either case ending up looking in 
database provided by that particular organization.

The graph also allows for certain links to 'skip a level'; but the
graph should certainly be cycle-free.

Someone who happens to know the *address* for a person (e.g. an
internet address as they now exist) is free to use it.  Some people
might even remember X.121 numbers they way we have to remember
telephone numbers, for a person's personal workstation.
But the object is to provide a system at least as good as the
telephone directory, and use the power of the computer to help people
figure out how to contact each other when they do NOT know the 
particular networks etc that are involved.

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After that is cleared up, perhaps we who have seen both the IFIP
proposal and the Internet plan could discuss the differences and
debate the merits? Personally I like the explicit heirarchial nature
of the Internet plan, and would like something like that incorporated
into the IFIP proposal, unless it's already there somewhere.
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In short, the hierarchy is there, but disguised because that seems
more likely to be useful.  Especially when the message systems get
really widespread.  But the Differences between the Internet plan and
the IFIP proposal are a result of one being a scheme for addresses
and the other a proposal for names.  The directories will mediate when
required.   In reality, the name form *has* to have a hierarchy
somewhere, because it would be quite impractical otherwise to
implement the directory servers.  The database will be far too large
to put all in one place, or to search without a good search strategy
and indexing scheme (say, 10 or 20 years from now).

		Julian Davies
UUCP   !uwo!julian
ENVOY  DJ.DAVIES