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From [e-mail]  Thu May 11 15:50:34 1995
1995
15:50:34 -0400
1995
12:22:31 -0500
To: [e-mail]



TELECOM Digest     Thu, 11 May 95 12:14:00 CDT    Volume 15 : Issue 237

Inside This Issue:                           Editor: Patrick A. Townson

    Job Opening at BellSouth (Chendong Zou)
    Re: RBOC IP Legislation Scaring Local ISPs (Tim Gorman)
    Re: Use of CDPD For Redundancy in Cellular Networks (John Agosta)
    Re: Mexico Billing Method: Digit Analysis or Meter Pulse? (Lars
Poulsen)
    Re: Voice/Data Multiplexer for 64kb Leased Line? (Dan Matte)
    Re: Calls From Australia to US 800 Not Delivering DTMF (Serge
Burjak)
    Re: Annoying Calls: Can We Deal With Them? (Bradley Ward Allen)
    Re: Annoying Calls: Can We Deal With Them? (Bruce Roberts)
    Extending Cordless Telephone Range (Greg Smith)

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----------------------------------------------------------------------



This is posted for a friend, please use the contact info. below:

ATTENTION:

1) In my previous posting on 5/9, I inadvertently forgot that our
Employment
Office needs to file your application.  As a result, I am reposting this
job
specs with the correction that individual candidate should send resume
to
([e-mail]).

2) The Internet address is used for all groups within Science &
Technology,
BellSouth Telecommunications.  Since there are openings in other groups,
You
may still want to send your resume even though your background may not
match
the job specs described below.

3) Search firms please do not response to this posting.  A subsequent
posting
describes detailed qualifications and steps to submit your candidate
resumes
will follow.

DATE: May 11, 1995

CONTACT: Send text resume to ([e-mail]) and reference to
Dr. Eric Kai.

LOCATION: Atlanta, Georgia

COMPANY:

BellSouth Telecommunications, which has revenues in excess of $13
billion and
assets of over $28 billion, has several R&D positions available in the
Wireless
Service Integration group of the Science & Technology department.  Our
charter
is to:

- provide technical support to BellSouth's business units in developing
and
implementing the business strategies for wireless market,

- conduct technical evaluation, requirement specifications,
system/software
engineering, prototype/product development and technical/marketing field
trials,

- R&D technical solutions to offer integrated/enhanced wireless services
to
BellSouth consumers and/or PCS service providers within our region,

- interact with vendor in product selection, requirement definition
and/or
joint development to support wireless products and services.

EXPERIENCE/SKILL:

Successful candidates should possess M.S. or Ph.D. in EE, CS,
Telecommunication, or related disciplines.  M.S. with a minimum of
three years of experience (or equivalent) in the wireless
telecommunication industry having solid working knowledge of wireless
networks such as cellular, mobile data and/or PCS is required.
Experience on system engineering, fast prototyping and software
development on wireless product and services is highly desirable.
Candidates must have expertise in at least one of the area below:

RF Design Area: solid experience in frequency planning, system growth
planning, cell site traffic analysis and RF propagation to conduct the
design/development of a Radio Planning tool for cellular/PCS network
under CDMA, GSM and TDMA.  Familiar with the air interface standards.

Wireless Data Area: working knowledge with wireless data technologies
such as CDPD, PCS data over CDMA and GSM, and/or other mobile data
applications.

Network Area: knowledge of SS7, ISUP and ISDN signaling and/or
transport. Good understanding of HLR/VLR/AM mobility management under
cellular/PCS for CDMA, TDMA and GSM.  Familiar with IS-41/GSM MAP.
R&D experience in the transparency of integrated wireline and wireless
services using AIN capabilities and other intelligent network
features.

OAM&P Area: experience in numbering plan, CDR/AMA, cellular rate plan,
billing services and downstream data processing and management.
Working background in designing/developing OSS such as PCS/cellular
network management, PCS performance tuning and traffic analysis,
customer trouble tracking, etc.

PERSONAL:

This individual must have:

- good interpersonal skills to work in a highly competent technical
team.

- motivation to understand the business needs of BellSouth and to find
effective matches between these needs and emerging technologies,

- ability to work in an effective, cooperative manner with other client
organizations within BellSouth as well as external companies.

OTHERS:

- Search Firm please do not response to this job post.  A subsequent
post will describe detail steps for you to send your candidate resumes.


Chendong Zou                                 Internet: [e-mail]
College of Computer Science, Northeastern University
360 Huntington Avenue #23CN, Boston, MA 02115     Phone: [phone]
WWW: http://www.ccs.neu.edu/home/zou              Fax:   [phone]

------------------------------



[e-mail] (Frank Atkinson) writes in TELECOM
Digest V15 #233:

> Without going too deeply into the regulatory system that built the
> network which took what the company spent, added a guaranteed rate of
> return, and in some cases hidden taxes, then passed it on to the rate
> payer's bill (rate of return regulation). The shareholder's position
> has been fairly well protected. Maybe each ratepayer should be given
> some company stock now that the network they built will be used to
> compete. The company hasn't sold enough stock to fund the network, the
> money came from the ratepayers, the ratepayers repaid the consturction
> bonds, not the stockholders.

If each ratepayer should be given stock in the telephone company then
why shouldn't each Ford owner be given stock in Ford? The car owners
repaid the debt issues (including debt bonds) of Ford, not the
stockholders. This is true of ANY company. The stockholders of Ford
certainly didn't repay the debt issues of Ford in order to provide
free cars to consumers.

The problem with this logic is that:

 1. The stockholders in the telephone companies did NOT make a killing.
The

    dividends were always very low compared to other companies of
similar

    revenues. The difference was that much of the company income flow
DID
    go to pay off debt issues as well as being reinvested. The
stockholders
    PAID a penalty for low risk by also incurring low yield.

 2. The telephone companies were NEVER guaranteed a rate of return. In
fact,

    the commissions set MAXIMUM rates of returns, not minimums. If rate
relief

    was requested by the telco during a rate hearing it was incumbent
upon the

    phone company to show that the rate of return during a measurement
period

    prior to the hearing was insufficient to operate the company and
attract

    sufficient capital. There were lots of years that the commission set

    MAXIMUM rate of return was never approached. By the same token,
having a

    MAXIMUM rate of return limit did not provide much incentive for
modern-
    ization, for creative service offerings, or for innovation. These
are
    things driven by competition.

 3. There is NOTHING wrong with reinvested earnings. Funding a capital

    intensive operation does NOT have to be done totally by shareholder

    investment in order to be "acceptable"

Once again, we see a view that somehow transforms the phone company
into being a non-profit, psuedo-government type of operation that
should be "owned" by all citizens since it was paid for by "psuedo-
taxes"
on the ratepayers masking as "rates" for services. The assets owned by
the shareholders should just be given away thus diminishing the value
of each share held by the shareholders. They just got rich by
trampling the "rights" of the ratepayers so who cares?

Folks, the phone companies have always been just that -- COMPANIES.
They have always been companies owned by shareholders -- just like
Ford, Pizza Hut, and Midas Muffler. Just like any other company, these
shareholders expected the company to make a profit and pay a dividend.
The amount of the dividend versus the investment was never near the
top but it was constant -- which is why AT&T stock used to be known as
the stock for little old ladies looking for a guaranteed income.

Since the telco's were franchised monopolies they were regulated. There
was
always two sides to the regulation:

 1. See that the ratepayer received the proper value for the rates being
paid.
 2. Allow the company to earn adequately to provide the required
service.

You may want to argue all day long on how good of a job the various
Public Utility Commissions did of regulation. You may even want to
argue whether having regulated monopolies did or did not do the best
for the consumer in the long run. But it is not valid to argue that
the telco's, companies OWNED by private citizens, should somehow be
nationalized. Those shareholders deserve an adequate rate of return on
their investment, just as the shareholders of MCI, Sprint, and J.C.
Penny deserve an adequate rate of return on their investment.


Tim Gorman    [e-mail]
Southwestern Bell Tel. Co (I speak only for myself)

------------------------------



[e-mail] (Seth B Rothenberg) writes:

> I recently did some work investigating CDPD.  One observation I made
> was that CDPD is an excellent way to gain redundancy.  In most areas
> (most populated areas?), there are two cellular carriers.  Since the
> last mile is what is at greatest risk, half of any circuit is
> protected 100%.

I'm not sure what you mean about 1/2 of each circuit ... but, not
understanding your situation entirely, I'll put in my two cents ...

> My question is about the other half.  Does anyone know if there is an
> easy way to, for example, have a router connection to both the A-side
> carrier and to the B-side carrier?  Then, you'd have almost perfect
> reduncancy.

Each carrier is considered its own domain, with different IP net
assignments / hosts etc.  In order to use both carriers, an account
would have to be established and IP addresses assigned to the M-ES for
each carier. On the land line side, you would need a connection to
your fixed end system from each carrier, meaning your router would
need two ports, one connected to each CDPD provider. Your M-ES would
need to be programmed with two IP addresses. (Many M-ESs can handle
more than one, CMI does ten for instance.)

Another way to work would be to use a single IP address, however,
inter-working agreements between the A and B carriers would have to be
in place, physical connectivity between the carriers would have to be
in place, and roaming charges (or similar) may apply.

(much deleted)

> What I am not clear about is, where the IP address is
> looked up.  Does the CDPD Mobile End Station know its own IP address?
> I would think it WOULD NOT need to know it, because the Data Service
> Manager would do that.

The CDPD mobile device does know its IP address, as per above. The IP
address "lookup" is done at a database in the carrier user signs up
with. The database is located in a "Home" function.  All authentication,
etc is done at this "home" function, regardless as to where the mobile
user actually is being "served" from. If I lived in Chicago, for
instance,
my "home" function would be in Chicago (or the closest one to my office
if there was more than one).

> If this is the case, the device would just have two IP addresses, one
> on each network.  My company's routers would need to be configured to
> route via whichever path is available.

One IP address is required if only one "home" needs to be consulted
for authentication purposes.  Hence, interworking must be done between
carriers A and B if one database is to serve the user.  One router
connection would be required as well in this scenario. If two network
"accounts" are being used, yes, you would need two IP addresses.

Did this help? I hope so.

If you email me, we can have a more detailed discussion.


John

------------------------------



In comp.dcom.telecom is written:

>> Does Mexico / Central America use a digit analysis method for
>> calculating charges, or a metered pulse method?  What I'm actually
>> refering to is the SMDR output on a PBX.  I believe the U.S. is in
the
>> minority in using digit analysis, or am I wrong?

In article <[e-mail]> Jan Hinnerk Haul
<[e-mail].
de> writes:

JHH> [for chargeback cost analysis] quite a lot of PBXes can do number
JHH> analysis as an alternative method [to reading billing pulses].
JHH> The drawback of number analysis is, of course, that no call
JHH> supervision is possible, letting users being "billed" with
uncompleted
JHH> calls if they wait longer than the set timeout period and letting
very
JHH> brief calls unbilled.

This is an oversimplification. Even without billing pulses, you are
not always limited to a simple timeout in determining whether the call
was answered. The real answer -- as usual -- is "it depends".

In some areas of the world [including specifically Denmark; I don't
have any experience with Hispanic America], you will in fact be billed
at the rate of the dialed number, even if the call was never answered.
The logic is that you have been tying up facilities along the call
path, just as if the call had been connected. Whether you get charged
for uncompleted calls is of course an administrative tariffing issue,
although it may depend on whether the switch is equipped to detect
whether the call was connected. (In some areas, where trunking is
analog, the information may not be available to the switch.)

Independently of whether you get charged for the uncompleted calls, you
may have either a short loop disconnect or a polarity reversal when the
call is connected. This depends on the specific switching equipment
that the line is connected to. Typically, the short disconnect is
seen on older mechanical switches, while the option to provide a
polarity reversal is available on newer switches.

Most administrations can provide a booklet defining the subscriber
interface, and saying that "you may see ..." this or that feature and
any equipment connected must be able to deal with all of these.  But
unless you have a technical contact in the repair bureau, you will
probably not be able to find out:

 - what switch type is serving a specific line
 - what options are available for that line on that switch, or

╖_


 - how the specific line is actually configured.


Lars Poulsen     Internet E-mail: [e-mail]
Rockwell Network Systems   Phone:        [phone]
7402 Hollister Avenue     Telefax:      [phone]
Santa Barbara, CA 93105    Internets: designed and built while you wait

------------------------------



In <[e-mail]>, [e-mail] (Magnus
Harlander) writes:

> We are looking for a data/voice multiplexer for a leased 64kb
> digital line. We want to use some portion of the bandwidth for phone
> calls to and from a PBX extension and the rest for IP traffic. The
> leased line speaks the G.703 protocol (there would be an alternative
> using I.430). Any information about implementations, producers and
> distributors is appreciated.

Memotec Communications Inc (Canada/US) also provides a solution for
this application that accomodates up to T1 speeds.  CX1000 Multimedia
Multiplexer 6/16 slot chassis

Modules available:

- Voice/Fax Compression
- Data Compression
- Ethernet & Token Ring bridging & routing
- Frame Relay
- Packet Switching
- 56K DSU/CSU
- FT1/T1 DSU/CSU

US HQ [phone]
Canadian HQ [phone]


Dan Matte   Memotec Communications Inc
Vancouver, British Columbia   [e-mail]

------------------------------



TestMark Laboratories <[e-mail]> wrote:

> Serge Burjak <[e-mail]> writes in TELECOM Digest Volume 15 Issue
226:

>> I have a problem getting through to some automated attendants using
>> DTMF from Australia. As the title says, after the connection the line
>> appears not to pass DTMF tones ie., "press 1 for this service, press
2
>> for that service."

>> This happens with both Telecom and OPTUS. The customer service droids
>> will not escalate the problem to anyone at an 'Engineer' level, but
>> only to techs who make comments like, well "the US is probably
>> translating these into something different, sorry cannot help you".

>> Am I being unreasonable asking to pass in voice band information? I
>> know it's not my phone, I can use Cyberlinks dial back for this or
>> AT&T's USA direct with a credit card. The Cyberlink solution is not
>> totally satisfactory for other resaons. The attendant requires a #
key
>> after the some transactions and Cyberlinks interprets this as a new
>> call request.

> The DTMF receivers in automated attendants are usually not up to the
> same quality as a Central Office DTMF receiver.  It sounds as if there
> is more loss on the Telecom and OPTUS connections than there is on the
> AT&T USA direct.  This surprises me, as I would assume that all are
> using digital transmission systems, which are "lossless!"

  ... lots of good stuff archived.

Thanks for the reply. I am hot on the trail of the problem. After much
screaming I got an OPTUS network engineer and SHE took me seriously.
They did some serious testing and it turns out, OPTUS and Telecom
Australia use the same LD carrier in the US to route the calls. It
appears when the remote answers, the LD invloved (one of the big
three) does not get an acknowledgement from this number to start
billing and enable the forward voice channel. It could be related to a
fraud prevention program, or more likely a poor implementation.

It's still broke on this one number that I NEED to use and I have
found a couple of others. Most other 800s appear to work.

Stay tuned.

------------------------------

key)


In article <[e-mail]>, Benjamin P. Carter
<bpc@netcom.
com> wrote:

> The PUC had ruled that an unlisted number would not be disclosed
> unless the caller chose to disclose it.  That's all.  Pac Bell
> asserted that too few customers would order caller ID under that rule
> to make it profitable.  And now the FCC has decreed that the calling
> number will be disclosed unless the caller specifically choses to
> block it.  This makes a difference because many (perhaps most)
> residential customers will ignore the whole issue of caller ID, doing
> nothing to either allow or block the display of their numbers when
> they make phone calls.  By default, their numbers will be displayed
> under the FCC rule.  The rule goes into effect December 1, 1995.  Pac
> Bell is happy with this rule and will offer CNID in 1996.

In retrospect, Pac Bell is right: I have CNID, and most the callers
who call me don't care or aren't aware of CNID.  Their numbers just
show up on my box.  Those who do care about CNID usually have gone out
of their way to block their lines.  Very few are aware and let it
show, and I bet that if they had to actually call and activate the
showing of their number, they wouldn't have done it.

If they had to actively turn it on, my CID box would be practically
useless.

However, I can see putting a recording on my line, which whenever I
received an Out Of Area or Private call would say: "Right now you can
reach me at 1-800-BRADLEY" or whatever, then hang up.  When they
called back, they'd go through my WilTel or other 800 number which
passes ANI via CNID ... (:

I would still find this useful.  I'm trying to figure out what
inexpensive
equipment I can get which would do this.


Bradley

------------------------------



Messrs. Greenberg and Cogorno have, quite properly, taken me to task
for getting the California PUC decision on caller-id wrong.  It was
*not* the fact that the PUC wanted per-line blocking as an option but
rather that they insisted all unlisted lines be per-line blocked by by
default.  My thanks to these gentleman for correcting me and my
apology to the participants for putting out wrong information.


TTFN -br-

Bruce Roberts, [e-mail]

------------------------------



I recently installed a cordless telephone (Partner Plus - AT&T CDM
9000) for a client.  The cordless gets great range when I locate the
base/charger near the outside wall of the building.  However, the
owner wants his base/charger located in his office in the middle of
the office building which severly limits his range and clarity when he
uses his cordless outside.

Is it possible to install an external antenna on the outside of the
building to improve the signal from the cordless base/charger?


Thanks,

Greg  [e-mail]


[TELECOM Digest Editor's Note: You can do this, but a couple problems
come to mind. You are not dealing with that much signal strength to
begin with, and some dissipation will occur in the coax between the
base unit and the rooftop antenna, which, IMO, will get you back to
about where you started, range-wise. It is also possible to open up
the base unit and 'peak' it up some if you know how to trim those pots
a little that you find inside. Know what you are doing please, before
you take a screwdriver to the inside of any radio transceiver. Most
cordless phones have how much power ... about a hundred milliwatts?
So maybe you get in there and *carefully* and *very slightly* adjust
the proper potentiometers to push the output up to ummm ... maybe a
quarter-watt; god forbid a half-watt if you get it just right. Try
not to blow out the final in the process, okay?

Now, let's say the proper peaking of the base got you that quarter-watt
of output, and you locate the base as strategically as possible, and
use as short a coax run as possible to get it to the roof to an antenna
preferably half-wave size. Notice how I emphasize *carefully* throughout
this message: after all, you are not running WLS 890 AM or KOA in
Denver,
with fifty thousand watts of power to splash all over the northern
hemisphere
all night long. Your supply is very limited. *They* don't give a damn
about Standing Wave Ratio (SWR) and such; why should they ... but you
need
every tiny bit of power you can tweak out of that base, making sure it
reaches the roof and a peice of metal which is conducive to proper and
efficient radiation.

So here we go: your antenna on the roof is now really blowing smoke.
That
cordless phone can get signals twice as far as before ... maybe even up
to three blocks away when atmospheric conditions are right and a lot of
other cordless phones in the vicinity are not being used. You should be
all set, right?  Wrong ... guess what:  the handset can hear the base
alright, but can't get back to it. Now you can tweak and peak the
handset
a little also, but you will *never* get it anywhere near the potential
strength of the base. For one, the components in the handset are a
little
different. At best, it has a chinzy little battery power supply which at
any given time is about half-way run down, compared to the base which
is plugged into the Edison line always getting lots of juice and always
ready to go. For two, the antenna on the handset is a compromise to make
it convenient to use. A half-wave antenna would be a burden due to its
size (length), so the manufacturer compromised with a loaded coil in
the phone making it 'think' its antenna was just as good as any other.

The handset can still hear the base alright; a call comes in and the
base sends a signal. The handset chirps and you turn it on; but it
just keeps on chirping because the base thinks you did not answer; after
all it got no signal back from the handset. Maybe you get slightly
within range of the base, and because the base is booming so well, the
modulation in your earpiece is fine .. perhaps too loud and too over-
loaded (depending on what pots you turned when you were in the base
messing around!  ha ha) but to the person on the other end your voice
sounds very distant, faint and even 'broken up' as other signals walk
all over your handset.  You sound like pooh ... as the CB'ers used to
say. Get back within the 'normal' operating range and the handset
works fine. All you basically accomplished by tweaking up the base
and installing your rooftop antenna was fixing things so the scanner
phreaks who spy on your cordless conversations could hear them that
much easier. Now instead of snoopy people a half-mile away listening
in, people a mile away get to listen also, but a fat lot of good it
does your client who gets only frustration when he tries to get more
than the 'usual' distance away with his cordless.

So after all your experiments at extending the range, the truth becomes
known: cordless phone bases are fixed 'the way they are' with the
little antennas they have for good reason ... there has to be a more
or less equal balance between the base *getting out* and the handset
*getting back to the base*. They work at about half their potential
(if everything inside was maxed out and the antenna was better quality)
because that's the best the handset can do in return. Unlike a broadcast
radio station, cordless phones take two to tango. I think you will find
attempts to extend the range or overcome barriers such as walls and
basements, etc have very limited success at best with cordless phones.
If additional range and reliable transmission is what your client needs,
we have a name for it: 'cellular service'. What success you will
accomplish
in increasing the range will only occur provided you also tweak the
handset a little, and then the results will be dubious at best.    PAT]

------------------------------

End of TELECOM Digest V15 #237
******************************