Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!orion.oac.uci.edu!ucivax!gateway
From: koorland@vancouver.osiware.bc.ca (Neil Koorland)
Newsgroups: comp.protocols.iso.x400
Subject: Re:  X.400 Questions
Message-ID: <9103271031*koorland@vancouver.osiware.bc.ca>
Date: 27 Mar 91 17:54:06 GMT
Lines: 35
Approved: usenet@ICS.UCI.EDU

>> It really depends on the non-X.400 addressing structure. For some (e.g.
>> RFC 822) there is an algorithmic mapping which requires minimal table
>> maintenance. For others there is more administrative overhead. However

> This is not completely true.
> RFC <-> X.400 does not imply an algorithmic mapping!
> It has been proven that only a table driven approach is able to handle
> every situation.

Your point is well taken. I deliberately oversimplified RFC987. The "minimal
table maintenance" referred to those aspects which RFC987 cannot handle
algorithmically. The point I was trying to make was that there
was no implicit need to have a 1-to-1 mapping for every address , in response
to Will's original question and concern.

>> the maintenance is not prohibitive with any reasonable system since
>> most address mapping only affects the most significant portions of
>> the address i.e. at the domain level.
>
>The experience shows that the maintenance is rather high
>with the first approach (the most widely used in the R&D community)
>The tables distributed yesterday are close to 100K big!
>The effort to maintain and distribute and install the tables
>is HIGH! In my mind the mapping table scheme will not be
>manageable within a few (2 3?) years.

"Rather high" does still not mean "prohibitive", and although I understand
the maintenance burden placed on RARE/COSINE administrators, not every
gateway administrator has to deal with tables of such complexity. It's also
worth mentioning that current work on MHS/Network management and Directory
Services is intended to solve problems in this area in the 2-3 year timeframe.

Regards,

Neil Koorland