Subject: RE: [Enum] ENUM Requirements

From: James Yu <[email-masked]>
Date: Thu, 9 Dec 1999 02:29:11 -0600

Bert,

I don't have any preferenece on how to get things done so long as the scheme
meets the requirements.  The "subscriber number (if connected with SCN)" is
used to find out the "routing number" which can be a routing prefix or the
Location Routing Number (in the U.S. and Canada).  That information then is
used to determine the proper GW(s) to go to based on routing information
from TRIP.  It is possible to combine the above into one step where the
information returned can be the GW(s)' IP address(es).  However, the routing
prefix or LRN information and/or the associated indicator (either the Nature
of Address (NOA) or the Forward Call Indicators) must be available to the
terminating GW so as to avoid another NPDB dip.

James
-----Original Message-----
From: Albert Manfredi [mailto:[email-masked]]
Sent: Wednesday, December 08, 1999 11:16 AM
To: James Yu
Cc: [email-masked]
Subject: RE: [Enum] ENUM Requirements

Related to number portability, without answering the specific
question, I would say that portable numbers _do_ make sense in the
name field of the DNS. Because a portable number is nothing but an
arbitrary ID, identical in concept to an Internet name.

The portable number is mapped to a "real" number, hierarchical and
used for routing, just like an IP name is mapped to an IP address.

So in my view, one possible way to support portable "telephone
numbers" is to map that arbitrary number to a "real" telephone
number (possibly in the AESA field), an IP address, or both.

To support mobile users, the DNS is not fast enough to track the MS.
In that case, the portable number could point to the "real"
telephone number of the _home server_, which in turn is keeping
track of the MS (via updates from the foreign agents).

Or, of course, one could imagine a real-time DNS, where the
databases are kept synchronized via satellite, but that's a whole
other program.

[email-masked]

James Yu wrote:

> NeuStar suggests to revise sectoins 3.7 and 3.9 (see
> proposed texts below)
> and clarify 3.11 in draft-ietf-enum-rqmts-00.
>
>  
>
> 3.7 Number Portability
>
> The system MUST support existing local number portability
> mechanisms that
> allow the subscribers to keep their phone numbers when
> switching from one
> local access service provider to another, where applicable. It is
> RECOMMENDED that the system not be designed in such a way
> as to impede
> future number portability that allows the subscribers to
> keep their phone
> numbers when moving from one physical location to another
> or changing their
> subscribed services. The system SHOULD be designed to
> meet the requirements
> set by the regulatory bodies.
>
>  
>
> 3.9 Query Performance
>
> The system is not expected to respond to queries with the
> same performance
> levels as current PSTN queries; however, the DNS process
> SHOULD not
> significantly increase the post dialing delay as
> percieved by the caller or
> specified by the regulatory bodies.
>
>  
>
> Please clarify "the owner of the telephone number" in
> Section 3.11. Is it
> the subscriber that is assigned the telephone number or
> the service provider
> that currently serves that number?
>
>
> _______________________________________________
> enum mailing list
> [email-masked]
> http://www.ietf.org/mailman/listinfo/enum
>

_______________________________________________
enum mailing list
[email-masked]
http://www.ietf.org/mailman/listinfo/enum

---

From: "Albert Manfredi" <[email-masked]>
Date: Thu, 9 Dec 1999 17:27:27 -0500

James Yu [[email-masked]] wrote:

> Location Routing Number (in the U.S. and Canada).

This is in response to my suggestion for portable numbers (included
below). Yes. That would be the effect. The portable number, when
dialed from an Internet appliance, might be dialed in as

[email-masked]

where the calling Internet appliance can be designed to add the @
symbol and the rest by default.

(Out of scope of enum: From a dumb telephone device, dialing these
portable numbers would be a matter of using a prefix first.
Different numbering plans would employ different prefixes, as
usually happens. The PSTN would keep its own number translation
databases, or it could use the DNS.)

Back at the Internet appliance, if this query goes to the DNS, and
if the DNS is set up with the E.164 encapsulated within its AESA
field as a _peer_ to the IP address field, then the DNS would reply
to the Internet appliance with whatever field(s) it has filled in.
It could be _just_ the AESA (a relatively dumb device perhaps), or
it could also be an IP address for e-mail or other possibilities.
Those more knowledgable about the DNS will have more creative
thoughts on this.

But more than that. The "portable (stable) telephone number" can
just as easily be translated to a "portable telephone name." Why
not? If you're using an appliance with a keyboard, there's nothing
to prevent that IP address/AESA combination from being listed with
several different IP names, right?

One "name" could be that [email-masked] described
above.

But another name could be [email-masked]. This
would typically be a shorter string of characters than the numbers
format.

So when you're dialing from a dumb telephone with just a keypad, you
have no choice. The numbers are used. Otherwise, you can use the
name.

The essential thing is to make the number to the left of the @
symbol globally unique. This permits the PSTN to use the same
permanent number.

And again, I think mobility can be assumed to work by means of home
servers which keep track of mobile stations' locations. Basically
what happens now with mobile stations.

Doesn't that meet the enum draft requirments?

Bert

  That
> information then is