Directory Services?

William Pimentel w-piment at UNIANDES.EDU.CO
Wed Sep 2 16:27:36 EDT 1998


Good point, Pete!  It's a shame you weren't on the call (there was a
certain amount of guesswork as to how 800 numbers work)!

There are two ways of handling this that I can see immediately.  Although
philosophically different, in practice they will normally amount to the
same thing:
1. The "owner" of a domain needs to be told where a query originates,
given that the calling location may affect the answer it gives or:
2. A border element handling queries for 800-type numbers needs to know
what to do with it depending on the origin of the query.

Dr Chris Purvis - Senior Development Engineer, WAVE CC Software
Madge Networks Ltd, Wexham Springs, Framewood Road, Wexham, Berks.
Phone:+44 1753 661359  email: cpurvis at

Dear All,

It may not be possible to handle 800 numbers in the same way as other
numbers as the destination may be based on the geographical location of
the caller.  For example, ISPs may be accessible by something like an
800 number which may be fixed for a whole country, but the POP you end
up connected to may vary depending on where you called from.

I'm not sure what the implications of this are, but it is something to
think about!!!


Pete Cordell
BT Labs
E-Mail: pete.cordell at
Tel: +44 1473 646436
Fax: +44 1473 645499

>From:  Chris Purvis WVdevmt-WS[SMTP:cpurvis at MADGE.COM]
>Sent:  02 September 1998 13:09
>Subject:       Re: H.323 Addresses
>>We are discussing about H.323 addresing schemes in our bi-weekly H.323
>>inter-GK conf calls.
>>The H.323 addresses that are being considered are 1. E.164, 2. E-mail,
>>URL, and 4. TCP/UDP/RTP port addresses (and 5. aliases as well I
>>Although a hierarchical notion of addressing scehmes have been
>discussed, we
>>have also recognized that some other variations of addressing schemes
>>For example, people change their physical locations, but they might
>>keep the same E.164 addresses. So, a translation is needed. Therefore,
>>very physical relationship of E.164 addressing scheme (e.g., knowing
>>and NXXs, one can find the distance) has been broken.
>I was under the impression that finally (after several weeks of
>discussion) we'd reached closure on this in last Thursday's call.  The
>solution that I understood had been agreed came in two parts:
>1. Mobile IP solves most of the problem for us - E.164 number resolves
>an IP address which may be anywhere in the world at any given moment in
>2. If a user wants to move (and take their number with them) to being
>an administrative domain with an otherwise reasonably contiguous E.164
>address space, this is easily handled as follows.  The domain that
>"should" (in the hierarchical sense) "own" the number that the user is
>keeping holds a record of where to contact the current holder of that
>number (which will typically be an entity to which an LRQ message can
>>Another example can be 800 numbers where the translation is also
>It seemed to be agreed in the call that 800 numbers are not a special
>case, but merely an example of number portability.
>>In addition, from mobility point of view (device or person) wired (and
>>wireless?) environement may also be looked into.
>Does this mean anything at all?
>>As we go froward, we may consider many of those aspects as pointed
>>provide solutions for the H.323 addressing schemes.
>I was under the impression that we'd reached closure on most of these
>Dr Chris Purvis - Senior Development Engineer, WAVE CC Software
>Madge Networks Ltd, Wexham Springs, Framewood Road, Wexham, Berks.
>Phone:+44 1753 661359  email: cpurvis at

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