Subject: RE: [Megaco] interpretation of H.248.23 andisp package and thedwa /data signals

From: "Wayne Cutler" <[email-masked]>
Date: Thu, 28 Apr 2005 10:05:40 +0100

Hi Kevin,

ETSI FSK delivery is described in ETSI EN 300 659 which has a section 
(6.1) called "Data Transmission Associated with Ringing" which is then 
further split into 2 sub-sections, namely "Data Transmission during 
Ringing" (6.1.1) and "Data Transmission Prior to Ringing" (6.1.2). 

Interestingly, the trasnmission that uses a TAS of RP is regarded as 
"prior to ringing" since the timings are different to the splash of 
ringing that is used 
for the "during ringing" scenario.

Therefore, the andisp dwa & data signals align nicely with the ETSI split 
and more than one company has interpreted the standard in this way and 
progressed to implementation. I would  disagree with your assertion about 
the procedures "clearly stating" this distinction. In fact, the cited UK 
example is incorrect since there are two methods used in the UK, namely 
the "BT method" which is prior to ringing (and uses a TAS or LR followed 
by DT-AS) and the "Bellocore" method used by Cable Operators (that uses a 
TAS of RP). 

I think it's a bit late to try and claim that the H248.23 words "during 
alerting" means "associated with alerting" - especially given the wording 
of the EN. 

Regards,
Wayne 

"Kevin Boyle" <[email-masked]>
27/04/2005 17:52

        To:     Wayne Cutler <[email-masked]>, [email-masked]
        cc:     [email-masked], [email-masked], [email-masked]
        Subject:        RE: [Megaco] interpretation of H.248.23 andisp package and thedwa /data 
signals

Your interpretation is incorrect.  The dwa signal is designed to perform 
data delivery associated with ANY alerting, whether prior to or during 
ringing.  This is clearly stated in the procedures section of the 
document.
Kevin 
-----Original Message----- 
From: [email-masked] [mailto:[email-masked]] On Behalf Of Wayne Cutler 
Sent: Tuesday, April 26, 2005 5:45 AM 
To: [email-masked] 
Cc: [email-masked]; [email-masked]; [email-masked] 
Subject: Re: [Megaco] interpretation of H.248.23 andisp package and 
thedwa/data signals 

>Question 1: 
>The description of the display with alerting signal in H.248.23 has the 
following text: 
>"Sends the display information to the CPE. This signal indicates that 
>the 
data must be applied during alerting ? either power ringing, or call 
waiting. >Therefore, this signal implies alerting, which will be 
appropriately applied to the CPE by the gateway, based upon the on 
hook/off-hook status of the >line."
>The ETSI specification, EN 300 659-1, On-Hook Data Transmission, 
>defines 
the following data transmission methods: 
>1. prior to ringing (including TAS equal to Ringing Pulse-Alert 
>Singal), 2. during ringing (ie between the first and second ringing 
>pattern) 
>Which signals defined in the andisp package should be used to support 
>the 
two methods because it is not clear from the andisp package descrition for 
dwa >signal can be applied for method 1? 

>Question 2: 
>Additionally it would be useful to find out what MG and MGC vendors 
>have 
implemented for methods 1 and 2. 
Hi Jan, 
For question 1, we'd read h248.23 as meaning that andisp/dwa should be 
used for option 2 (during ringing) and andisp/data for option 1 (prior to 
ringing).
In terms of question 2, this is what the Marconi CA & MSAN has 
implemented. 
Regards, 
Wayne 

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---

From: "Dal Chohan" <[email-masked]>
Date: Thu, 28 Apr 2005 15:11:34 +0100

Hi Wayne,

>From reading the e-mails there appear to be two different approaches for
providing "On-Hook" display associated with ringing using the H.248 "andisp"
package. 

One approach assumes that the TAS signal is determined/provisioned within
the MGC (i.e. andisp/data) and the other approach that assumes the TAS
signal is determined/provisioned in the MG (i.e. andisp/dwa).

I can understand why a number of implementations have adopted the former
approach, because it provides a single and consistent mechanism for
delivering "On-hook" display "during ringing", "prior to ringing" and "not
associated with ringing". Moreover it means that a single signal
"andisp/data" can be used for delivering all variants of the "On-Hook" and
even the "Off-Hook" display service. 

If the latter method is used, then it means the two different signals must
be used. The signal "andisp/dwa" for "On-Hook" display associated with
ringing. The signal "andisp/data" for "On-Hook" display not associated with
ringing. Also the TAS signal for the "andisp/dwa" case is
determined/provisioned within the MG, while for the "andisp/data" case the
TAS is determined/provisioned within the MGC.  This does mean things are
modelled differently for the two cases and this does seem to be an odd
approach and incorrect from a service modeling and provisioning perspective.

We can either try to mandate that "andisp/dwa" is used for "On-Hook" display
prior to and during ringing, but there appears to be a lot of benefits and
mileage in allowing "andisp/data" to be used for "On-Hook" display prior to
ringing, during ringing and not associated with ringing- especially since a
number of implementations have already adopted this approach.

 

Regards,

Dal.

 

  _____  

From: [email-masked] [mailto:[email-masked]] On Behalf Of
Wayne Cutler
Sent: 28 April 2005 10:06
To: [email-masked]
Cc: [email-masked]; [email-masked]; [email-masked]
Subject: RE: [Megaco] interpretation of H.248.23 andisp package andthedwa
/data signals

Hi Kevin, 

ETSI FSK delivery is described in ETSI EN 300 659 which has a section (6.1)
called "Data Transmission Associated with Ringing" which is then further
split into 2 sub-sections, namely "Data Transmission during Ringing" (6.1.1)
and "Data Transmission Prior to Ringing" (6.1.2). 

Interestingly, the trasnmission that uses a TAS of RP is regarded as "prior
to ringing" since the timings are different to the splash of ringing that is
used 
for the "during ringing" scenario. 

Therefore, the andisp dwa & data signals align nicely with the ETSI split
and more than one company has interpreted the standard in this way and
progressed to implementation. I would  disagree with your assertion about
the procedures "clearly stating" this distinction. In fact, the cited UK
example is incorrect since there are two methods used in the UK, namely the
"BT method" which is prior to ringing (and uses a TAS or LR followed by
DT-AS) and the "Bellocore" method used by Cable Operators (that uses a TAS
of RP). 

I think it's a bit late to try and claim that the H248.23 words "during
alerting" means "associated with alerting" - especially given the wording of
the EN. 

Regards, 
Wayne 

27/04/2005 17:52 

        To:        Wayne Cutler <[email-masked]>,
[email-masked] 
        cc:        [email-masked], [email-masked],
[email-masked] 
        Subject:        RE: [Megaco] interpretation of H.248.23 andisp
package and thedwa        /data signals

Your interpretation is incorrect.  The dwa signal is designed to perform
data delivery associated with ANY alerting, whether prior to or during
ringing.  This is clearly stated in the procedures section of the document. 

Kevin 

-----Original Message----- 
From: [email-masked] [ <mailto:[email-masked]>
mailto:[email-masked]] On Behalf Of Wayne Cutler 
Sent: Tuesday, April 26, 2005 5:45 AM 
To: [email-masked] 
Cc: [email-masked]; [email-masked]; [email-masked] 
Subject: Re: [Megaco] interpretation of H.248.23 andisp package and
thedwa/data signals 

Hi Jan, 

For question 1, we'd read h248.23 as meaning that andisp/dwa should be used
for option 2 (during ringing) and andisp/data for option 1 (prior to
ringing). 

In terms of question 2, this is what the Marconi CA & MSAN has implemented. 

Regards, 
Wayne 

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Megaco mailing list 
[email-masked] 
 <https://www1.ietf.org/mailman/listinfo/megaco>
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