telephone URLs, comments on draft-antti-telephony-url-04

Larry Masinter (
Thu, 25 Jun 1998 23:53:18 PDT

From: "Larry Masinter" <>
To: "Vaha-Sipila Antti" <>
Cc: "URI distribution list" <uri@Bunyip.Com>
Date: Thu, 25 Jun 1998 23:53:18 PDT
Message-ID: <002901bda0cf$196ead00$>
Subject: telephone URLs, comments on draft-antti-telephony-url-04

I've been reconsidering the position on telephony URLs in light
of recent discussions about the generic URI document.

I suggest removing "local-phone-number". In the case of
the fax specifications, there was always an 'offramp' to which
the phone number was being made local, but in the case of the URL,
there is no context.

A URL is a Uniform Resource Locator, and "uniform" means that a
URL should identify the same resource no matter where it is accessed.
If there is some context that is missing, then relative URL forms
are used, with the base supplying the rest of the form.

I suggest (re)considering the URL-style form

global-phone-number = //<countrycode>/<citycode>/<number>...

(although the production should change from "global-phone-number"
to "global-phone-path" or some such, since it is no longer just
a 'number'.)

so that you would write 
instead of

This is consistent with the URI generic syntax.

It also makes it feasible to have some contexts where the country
code or citycode are elided.

Local dial strings _could_ be accomodated with post-dial.

I would like to (re)consider whether separate schemes for
'tel', 'fax' and 'modem' should be used, rather than having
the 'call style' be a parameter, if such is necessary.
The URL uniformly locates the resource, and doesn't need to
specify the service that is to be obtained at that resource.

These topics may have been discussed in the past, but I'm having
trouble locating the archive, and the justification for the design
decisions aren't in the draft. I apologize for revisiting topics,
but I see there is renewed interested in this topic, and I'd like
to get it 'right'.