Subject: RE: [Megaco] New parameter for digit completion event

From: "Kevin Boyle" <[email-masked]>
Date: Wed, 7 Aug 2002 11:16:22 -0400

Comments inline. [KJBII]

Kevin

-----Original Message-----
From: Al Varney [mailto:[email-masked]]
Sent: Tuesday, August 06, 2002 7:24 PM
To: [email-masked]'
Subject: RE: [Megaco] New parameter for digit completion event

At 02:15 PM 8/6/02 -0700, John Stock wrote:
>Even though dial pulse is old technology, it's certainly still prevalent.
>I've seen somewhere that about 15% of U.S. lines still use dial pulse, and
>about 60% non-U.S.  ....  At any rate, there are many
>people still using dial pulse, and all their phones will stop working if
>their access network is changed to next-gen and pulse dialing is not
>supported.

    While many US TELCo's allow DTMF dialing without added charge (Kevin's 
assertion), this is not true nationwide (particularly in rural areas).  Nor 
have any TELCos required homeowners to discard DP phones or switch 
dual-mode phones to DTMF.  In fact, that's probably an impossible 
requirement.  As a example, I have a DP-only phone in my basement -- mostly 
to answer incoming calls.  I'd like to be able to dial 911 if I'm trapped 
by a tornado in my basement.  Many of the old Bell System DP phones from 
the 1950s are still connected to DTMF-capable lines.

[KJBII] Hmmm... I guess it's too much trouble to go to Wal-Mart and buy a
$10 phone that does DTMF.  Certainly telcos would have to notify their
customer base that pulse will no longer work, just as they do if they are
changing the area code.  But I really don't know of many people that would
complain.  If it is that much concern that we maintain pulse technology
until the end of time, then detect the pulse digits while detecting DTMF,
and report them in the DTMF package.  Or invent a new package.  But I still
assert that pulse has exceeded its useful lifetime, and we shouldn't
necessarily propogate it just to keep it around.

[KJBII] As for billing, the rural telcos that charge for DTMF aren't really
known as being on the cutting edge.  Many of those same telcos still have
multiparty lines!  You aren't in favor of propogating party lines too, are
you?  Remember, this is new technology.  Telcos that want to continue to
support older technology can do so, by not upgrading.

    And this isn't a US-centric protocol anyway, is it?

[KJBII] DTMF is an international standard.  I am probably the last person
that can be accused of being US centric in my protocol additions, since all
the packages I have written have been with an eye to international use.

    I think one assumption in this discussion is that Kevin is probably 
thinking of a "residential gateway" owned by a 
homeowner/business-owner.  Such an owner would likely upgrade any DP phones 
to DTMF when installing the gateway.  I'd agree with Kevin that such 
gateways probably don't need to support DP.

[KJBII] Your assumption cannot be further from reality.  I am not thinking
of a residential gateway.  In fact, I try not to think in terms of specific
applications of gateways.  That leads to inconsistencies in the protocol
across applications.

   John is instead thinking of a "line access gateway", providing service 
to multiple homes/businesses -- perhaps as a flash cut-over from an 
existing switch.  In such cases, one MUST continue to provide DP service 
because no one can be sure there isn't a DP phone on one of the lines.  So 
such gatways MUST support DP and DTMF simultaneously on a given line.

[KJBII] I work every day on a large-scale MG line access product on which
Nortel is deploying 3.6 million H.248 based lines (press release URL--
http://www.nortelnetworks.com/corporate/news/newsreleases/2001d/11_05_01_spr
int_voip.html).  I assure you, these are not "bolt-to-your-house" MGs.  I
can also assure you that DP is not a concern -- the number of customers that
are DP is pretty small and, of those, the number that have ONLY rotary
phones is minimal.  If it is such a concern to support DP, I have provided a
couple ideas above.

>   Now that digits are (or can be) collected in the access network
>instead of the C.O., an indication is needed as to what collection method
>was used.  In addition to the SS7 indication, it's also needed for MF
>pulsing on tandem CAS trunks, when pulsing carrier access codes (KP vs.
>KP'', etc.).

    While the MF/SS7 indications are useful, they are relatively new and 
not universally provided by today's network.  What IS required by any Class 
5 softswitch with line access gateways is an indication of DP/DTMF for 
billing and reporting purposes -- in the USA and elsewhere.

Al Varney

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---

From: Rajeev K R <[email-masked]>
Date: Thu, 08 Aug 2002 15:33:13 +0800

Hi,
I have another question regarding the digit detection.
In which case it is necessary for the MGC to know what was the dialling
method ?
A digit reported in DTMF is going to be processed by the MGC in the same way
as the digit reported by DP. So for MGC the only requirement is that the MG
should
report the digits even if the phone is DP.

An MG may support both the DTMP and DP detection. When the MGC asks it to
detect a
digitmap completion event on a terminal, let the MG do it irrespective of
the type of phone.
I think the issue is only related to name of the package, it should have
been just digit detection package
instead of DTMF detection Package. If we name the package as digit detection
package and add a sentence that this can be used for both DTMF and DP the
issue is solved.

Kevin,
Was there any particular reason for naming the package as DTMF detection
when it could have been generic enough as digit detection ?

Regards,
Rajeev

---

From: Rajeev K R <[email-masked]>
Date: Thu, 08 Aug 2002 15:33:13 +0800

Hi,

Kevin,

Regards,
Rajeev