Subject: RE: [ipcdn] Tx-Rx loss plan and Tone Table

From: "Sumanth Channabasappa" <[email-masked]>
Date: Thu, 23 Jun 2005 07:48:15 -0600

Phillip,
 
Appreciate this email. But you say that 'Apparently the review of the
MIB Doctor re-structuring of the Tone table focused on the problem at
hand but failed to fully review previous tone structures.  This has
resulted in the current situation where the current SigMIB draft fails
to meet the requirements of the original PacketCable Supervisory Tones
such as ROH Tone which is generated by combining four tones at
frequencies of 1400 Hertz, 2060 Hertz, 2450 Hertz and 2600 Hertz at a
cadence of 0.1 second on, 0.1 second off, repeating.'
 
Can you check my response to Satish's mail yesterday with Gordon's
example and let me know if that helps at all (I shall worry about the
MIB doctors)?
 
Thanks!
Sumanth

  _____  

From: Freyman Phillip-FPF300 [mailto:[email-masked]] 
Sent: Thursday, June 23, 2005 6:01 AM
To: [email-masked]'
Subject: [ipcdn] Tx-Rx loss plan and Tone Table

Collegues,
 
The email chain on these topics has been quite active begining with
IPCDN Digest, Vol 13, Issue 2 and through Issue 8.
 
I would like to make a few comments at this time.
 
The original submission to re-establish the Tx-Rx gain/loss requirement
was submitted to the distribution list on 15 February, 2005.  So the
reason and rational for this re-statement goes back 4 MONTHS not 5 days.
In that submission a number of Telephony standards across world markets
were identified and quoted and the rational for the return of the
requirements was stated.
 
There are several points in the current gain/loss plan discussion.
1.  Should the Tx-Rx gain/loss requirements be in the SigMIB?
2.  If they are to be included, what is the range of values
3.  If they are to be included, what are the default settings.
 
The current view of the respondents tends to focus on the need for the
requirements in the SigMIB.  This implies that no one has recognized the
need to change the gain/loss requirement on any dynamic basis, either on
a per call basis or within a call.  Without support for this in the
SigMIB, the gain/loss requirement becomes fixed either by physical
hardware design or vendor specific provisioning MIB approaches.
 
The questions on the range of values and defaults are a "mute point" if
the basic Tx-Rx gain/loss is removed, however some considerations.
1.  PacketCable defines gain/loss at -2 dB
2.  ETSI defines gain/loss up to -11 dB
3.  Most operators and field experience tend to set the loss to -4 dB.
3.  Some worldwide operators tend to select values within these
settings.
4.  Based on the various standards or operator requirements, a range of
0 to -12 dB of gain (0 dB to 12 dB loss) seems acceptable.
5.  Based on the various standards or operator requirements it would
appear Tx gain and Rx gain in PacketCable architectures should default
to 4 dB but ETSI based architectures should default to Tx at 4 dB but Rx
at 11 dB.
6.  Operators may defined other defaults based on local requirements.
 
However, since the group appears to believe a "fixed" gain/loss plan is
adequate, then Motorola withdraws the 15 February, 2005 proposal to
re-instate the requirements and the discussion of range and default
settings are a mute point.
 
This decision will also impact the pktcSigDevToneDbLevel since this
requirement references the pktcNcsEndPntConfigRxGain entry.
 
The other point of discussion and the one which is more significant is
the Tone table structure.  During the earlier SigMIB review process some
problems were found with some international tone requirements with the
original four frequency structure.  Proposal to that structure were
submitted to the working group to resolve the problems seen at that
time.  During review of this proposed change, one of the "MIB Doctors"
required a change to the structure to "simplify" the structure.
Apparently the review of the MIB Doctor re-structuring of the Tone table
focused on the problem at hand but failed to fully review previous tone
structures.  This has resulted in the current situation where the
current SigMIB draft fails to meet the requirements of the original
PacketCable Supervisory Tones such as ROH Tone which is generated by
combining four tones at frequencies of 1400 Hertz, 2060 Hertz, 2450
Hertz and 2600 Hertz at a cadence of 0.1 second on, 0.1 second off,
repeating.
 
At this time only one proposal to correct the ToneTable structure has
been made and NO comments have been offered to provide alternate
structures or to accept the submission as it.
 
Personally I must still review the proposed ToneTable change but it does
seem the WG should re-focus their efforts on the significant issue at
hand.
 
Regards,
 
Phillip Freyman
Distinguished Member of the Technical Staff
Science Advisory Board Associate
Motorola, Inc.
Connected Home Solutions IPS
IP System Engineering
21440 West Lake Cook Road
Deer Park, IL 60010

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From: "Randy Presuhn" <[email-masked]>
Date: Thu, 23 Jun 2005 18:55:09 -0700

Hi -

The "MIB Doctor" perspective on the tone table is that what we
were given to review had far more objects and complexity than were
necessary for it to do what it was described as doing.  Whether
what it was doing is adequate for the WG's needs is a separate
question.  MIB Doctors generally assume the working group knows
what it wants to model; we just make sure that the MIB representation
is reasonably sane.  In the case of the tone table, it apparently needs
to be able to represent a richer variety of tones than *any* of the
MIB versions I've seen would be able to do.  I suggest you get
agreement on how much expressive power the tone table needs,
and *then* get down to the nuts and bolts of deciding how to represent
it.

Randy