Subject: RE: [Megaco] H.248 equivalent of MGCP Delete from MG

From: "David Barr" <[email-masked]>
Date: Tue, 14 Aug 2001 17:12:21 +0100

So in my cases below, I assume you mean using nt/qualert with threshold=100%
... is this correct?
 
For case (1), I would think nt/netfail would also be a suitable event ...
correct?
 
However there is a problem with using events to do this.  If the MGC doesn't
request the event, it obviously won't get informed of the problem and
therefore the call won't be cleared (... well, not until the users hang-up
in frustration.)
 
The advantage of the MGCP approach was that the MGC got to know about the
problem without explicitly having to ask for it everytime it set up a
connection.
 
Ok, back to nt/qualert ... is it standard practice for the MGC to request
this?  None of the example call flows I have seen show the MGC requesting
nt/qualert.
 
Regards,
Dave.
 
-----Original Message-----
From: Madhu Babu Brahmanapally [mailto:[email-masked]]
Sent: Tuesday, August 14, 2001 4:45 PM
To: Barr, David [HAL02:HF22:EXCH]; megaco
Subject: RE: [Megaco] H.248 equivalent of MGCP Delete from MG

Hi David,
In H.248, its only the MGC that can subtract the terminations from the
context. In case of packet-side failure/comfort noise or any other case MG
has to only indicate using the quality alert event and MGC will take the
necessary action. 
Regards
Madhubabu

-----Original Message-----
From: [email-masked] [mailto:[email-masked]]On Behalf Of David
Barr
Sent: Tuesday, August 14, 2001 11:20 AM
To: [email-masked]'
Subject: [Megaco] H.248 equivalent of MGCP Delete from MG

Hello list, 

MGCP has the concept of a Delete from the MG to the MGC. 

So what do we do for H.248 ?  The Subtract command is intended for MGC to MG
only. 

The MG may need to use this under certain circumstances.  Examples are: 
(1) If there is detection of a packet-side bearer failure which affects a
ephemeral termination within a current context.

(2) If the MG fails to detect voice (or comfort noise) on a bearer
connection after a certain amount of time -- this may be due to a problem
with the peer MG, rather than anything wrong with the network.

(3) A temporary MG resource issue which caused it to drop the call, but
shouldn't affect future calls. 

Is there a standardised way for the MG to convey this infomation to the MGC
-- i.e. one which all MGCs will understand? 

Thanks.

---

From: "Madhu Babu Brahmanapally" <[email-masked]>
Date: Tue, 14 Aug 2001 14:10:24 -0400

H.248 equivalent of MGCP Delete from MGHI David/All,

MGC,  if interested to receive such events, has to sent those events in the
events descriptor or event buffer descriptor (Not shown in Example call
flows). Both "netfail" and "quality alert" can be used for this purpose.(as
applicable).  The method of calculating the threshold for percent of quality
loss is based on some provisional method. (I initially thought that the
protocol will suggest few methods for this calculation, I'm not sure how
this calculation is done.)

Regards
Madhubabu
  -----Original Message-----
  From: David Barr [mailto:[email-masked]]
  Sent: Tuesday, August 14, 2001 12:12 PM
  To: 'Madhu Babu Brahmanapally'; megaco
  Subject: RE: [Megaco] H.248 equivalent of MGCP Delete from MG

  So in my cases below, I assume you mean using nt/qualert with
threshold=100% ... is this correct?

  However there is a problem with using events to do this.  If the MGC
doesn't request the event, it obviously won't get informed of the problem
and therefore the call won't be cleared (... well, not until the users
hang-up in frustration.)

  Regards,
  Dave.

  -----Original Message-----
  From: Madhu Babu Brahmanapally [mailto:[email-masked]]
  Sent: Tuesday, August 14, 2001 4:45 PM
  To: Barr, David [HAL02:HF22:EXCH]; megaco
  Subject: RE: [Megaco] H.248 equivalent of MGCP Delete from MG

  Hi David,
    -----Original Message-----
    From: [email-masked] [mailto:[email-masked]]On Behalf Of
David Barr
    Sent: Tuesday, August 14, 2001 11:20 AM
    To: [email-masked]'
    Subject: [Megaco] H.248 equivalent of MGCP Delete from MG

    Hello list,

    So what do we do for H.248 ?  The Subtract command is intended for MGC
to MG only.

    The MG may need to use this under certain circumstances.  Examples are:
    (1) If there is detection of a packet-side bearer failure which affects
a ephemeral termination within a current context.

    Is there a standardised way for the MG to convey this infomation to the
MGC -- i.e. one which all MGCs will understand?

    Thanks.