TELECOM Digest     Fri, 13 May 94 11:44:30 CDT    Volume 14 : Issue 222

Inside This Issue:                           Editor: Patrick A. Townson

    Re: Can Residential Voltage (?) Drop? (balcroan@netcom.com)
    Re: Graceful Degradation (Bill Tighe)
    Re: What is the Mercury Button? (Neil Watson)
    Re: Government Regulates Number of Modem Redial Attempts? (Kaita Seikku)
    Re: Government Regulates Number of Modem Redial Attempts? (Chip Sharp)
    Re: GSM and Airbags (David Breneman)
    Re: 3270 Emulation (Jack Hamilton)
    Re: 3270 Emulation (William M. Eldridge)
    Re: Meeks Defense Fund (Stephen Cohoon)
    Re: Searching For a Specific Telephone (Steve Cogorno)
    Re: Delrina Fax MailBox Retrieval and Class 2 Modems (Jack Bzoza)
    Re: Cellular Call Forwarding (John Musselman)
    Digital MSK Modem Questions (christos@kuhub.cc.ukans.edu)
    Request For an FTP Site For X509 (Pat Worden)

TELECOM Digest is an electronic journal devoted mostly but not
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----------------------------------------------------------------------

From: balcroan@netcom.com (Butch lcroan/.nameBalcroan Lilli) 
Subject: Re: Can Residential Voltage (?) Drop?  
Organization: NETCOM On-line Communication Services (408 261-4700 guest) 
Date: Fri, 13 May 1994 07:29:25 GMT


balcroan@netcom.com wrote:

>>> Is voltage somehow involved in "ringing" so that a decrease would
>>> cause to small a *something* for devices like modem cards and handsets
>>> to respond to?  Where does this happen, and what's the fix? 

>> Ringing is a low-frequency AC signal applied to the line (Typically 90
>> volts at 20 Hertz).  Tell the repair desk that "ringing voltage is not
>> being applied".  They will likely find the problem to be the line
>> equipment (printed circuit card in modern exchanges) feeding your
>> line.

> If the above call to the local TELCO doesn't work please submit
> private e-mail and I will give you the answer you can then decide if
> you want to make it public after it is tried ... BTW if it is what I
> suspect it is be prepared for the other line to have the same problem
> shortly ....

> [TELECOM Digest Editor's Note: Do tell us more!  PAT]

I am not sure all problems mentioned above relate to this little
problem about to be mentioned ... but always be aware there is the
possibility of a "PAIR-GAIN DEVICE" or "SUBCRIBER CARRIER" between the
voltages the CO generates on analog tip and ring pair and the analog
tip and ring pair that is attached to the phones in question. I would
also like to caution regarding all phones as there is no way the
phones you get free from {TIME & LIFE} for a subscription is as good
as the NTI, AT&T, GTE or other phones purchased at the Phone-Mart in the
mall.

1.) PAIR GAIN devices are of various generations and some work better
than others at ringing more phones than one. The voltage and current
can both be in question.

2.) The capacitance can vary greatly between a "cheapie" phone and a
more expensive phone. There is also the resistance between the T & R
that can cause a shorting or shunting of a AC signal such as the
ringing voltage.

This can also cause the phone to ring once and then stop because of
the momentary short cause by the insulation breakdown cause the 20
milliamp current caused by a off hook condition. This is read by the
CO as an answer! Then the ringing stops and so does the current flow
and ooooppps no answer! This was found to be the case in a state that
will remained unnamed ... we (NTI) had a engineer camped out at the
customer site wait for the problem to be reproduced and as he was
watching TV on came an advertisement ... he went to the store in the
mall that was giving away one of these phones for free just for coming
down ...  well it was tested next day and the above was found. They
had been giving them away all month long. This was the problem that
had went to a VP level to find ... oh BTW a Automatic Line Insulation
Test (which had been requested at least three times by NTI but telco
said NO IT WOULD BE A WASTE OF TIME) found several of these "$3.95" 
phones ... not a defective piece of software as the telco had suggested.


Butch     email balcroan@netcom.com

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

From: bill@noller.com (Bill Tighe)
Subject: Re: Graceful Degradation
Date: 13 May 94 11:24:24 GMT


levin@1.121.159.165.in-addr.arpa (jerry levin @ Trident Data Systems)
wrote:

> Can anyone explain to me what is meant by graceful degradation when
> referring to a data bus?

Computer redundancy can be implemented in many ways and the method
used depends on the demands of the application.

"Graceful degredation" refers to a redundancy method used for
applications where it is advantageous to keep all resources on line
when they are functional.  As modules fail they are taken off line and
the total computer power is reduced.  Thus computer power "gracefully
degrades" and error recovery techniques hide the failure from the
users.

Sequoia uses this method for on line transaction processing.  Computer
modules, 68xxx I beleive, run in parallel and if one fails, the load
is shifted to the remaining units.  Users may notice an increase in
response time but they still have a working system.

Since no expensive modules are sitting idle, the customer gets high
performance and reliability for the lowest possible cost.

Some applications such as aircraft control cannot work with a degraded
computer so full idle backup units must be used.  Some aircraft
systems have triple redundancy, two backups for each working computer.
Expensive but necessary.


Bill Tighe             Email:  bill@noller.com
Phone:  707-778-0571   FAX:    707-778-0235

PCMCIA; People Can't Memorize Computer Industry Acronyms

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

From: nwatson@Aspect.COM (Neil Watson)
Subject: Re: What is the Mercury Button?
Date: Fri, 13 May 1994 13:13:11 GMT


In article <telecom14.211.2@eecs.nwu.edu> johnper@bunsen.rosemount.com
(John Perkins) writes:

>>> Detailed question about Mercury button deleted.

The Mercury button is a slightly special "one press" memory button.

To access Mercury you need to dial their access code (131 for the 2200
service), wait for dialtone again (high pitched noise) then dial a 10
digit PIN (for identification) followed at last by the called number.

The additional complexity is that the Access code will have to be
dialled in whichever mode your BT exchange will support (ie it may
have to be pulse) and the rest of the number after the Mercury DT has
to be DTMF (tone). Thus a phone that can switch between pulse and tone
dialling mid-way through a memory dial is a requirement. If you're in
a tone-dialling area (which is most exchanges now), then this isn't an
issue.

Other things that go into the "suitability" for use on Hg are the
ability to sequentially dial memories (to dial a certain relative we
dial mem 1 followed by mem 5) and the ability to dial other numbers
while the phone is still dialling the memory. Also your "last number
redial" register needs to be 24 digits or so!

 From this information you will realize that it is not strictly
necessary to have a phone with the fancy blue button to use Mercury. I
personally have a normal phone that I've programmed mem 1 to do the
Mercury predial and it works just fine. Then again a single, clearly
identified button to identify the long distance carrier is simpler.

Another thing to take into account is Mercury's recently announced 132
service which uses ANI/CLI to determine the authenticity of the
caller.  To use this you only need dial 132 followed by the called
number.  Unfortunately it requires a modern BT exchange and so isn't
available everywhere that can access Mercury yet ... (yes, I know CLI
isn't available to subscribers in the UK yet, but LD carriers are a
different matter.)

> They have a perfectly good BT "Tribune" phone set that has some
> special attachments for the hearing impaired, but are under the
> impression that they can't use it if they want to use Mercury. (I have
> a feeling that they don't really need the Mercury phone set at all.)

I don't know about the Tribune -- many of the BT sourced phones didn't
have sufficient memory versatility to do the job for a Mercury Blue
button, but may well have enough for 132 access.


Good luck,

Neil

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

From: spk@proffa.cc.tut.fi (Kaita Seikku)
Subject: Re: Government Regulates Number of Modem Redial Atttempts?
Date: 13 May 1994 07:12:42 GMT
Organization: Tampere University of Technology, Computing Centre


TELECOM Digest Editor noted:

> ... Some people, you see, leave the speaker turned off all the time
> and as a result don't even realize they are connecting to a live
> person in errror instead of another modem. I would rather have seen a
> rule saying that if voice was detected instead of carrier, the speaker
> would automatically turn on ...

What if the modems were equipped with DTMF receive capability, and
then the software while waiting for the connection to establish, would
fall back if any DTMF was detected? (Then it would just be tough to
those people who would not know about the DTMF implementation  ...)

Or actually, my real opinion :

As the new features are programmed into the switching software, there
should be a new command (like *21*redirection) to ignore calls from
the number that last called me (which would be a great help against
those "%$&/()= phone sales persons, too).

Of course thers's a problem in this, too, since your (B-subscriber's)
switch does not always get the A-subscriber number complete. (I mean
the old technics, not the deliberate disabling of caller ID, there
should be a command to ignore ALL calls that have been originated with
caller-ID disabled).


internet : spk@proffa.cc.tut.fi  answering machine->pager : +358 -43 498 0297
real life: Seikku P. Kaita                 phone (or FAX) : +358 -31 265 6865
visit at : Saastajankuja 4b32 TAMPERE         On The Air  : OH3NYB
            ^^  ^ ^  ..these four a's should have double dots above them, 
           since they are front vowels (as in word 'that'). Isn't it a pitty
           that in English the word GHOTI can be pronounced like word FISH.  


[TELECOM Digest Editor's Note: Actually the feature you suggest has been
implemented. Call Screening allows either the entry of a number from which
the subscriber no longer wishes to receive calls or if that number is not
known (because the calling party blocked his ID) an entry for 'last call
recieved' in which case the CO will note the number and block further calls
 from it to the recipient even though the recipient is not given the number
in an effort to avoid violating the privacy of the caller.  Here in Illinois
Bell territory, we use *60 to add/delete numbers to our Call Screening
directory. If thus screened, the calling party gets an intercept message
saying the called party 'is not receiving calls at this time.'  It does not
say 'is not receiving calls from *you*' ... just 'not receiving calls'. Of
course the calling party can go to another telephone if they wish, but few
people bother; they simply take the hint and don't call back.  PAT]

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

Date: Fri, 13 May 94 08:22:29 EDT
From: hhs@teleoscom.com (Chip Sharp)
Subject: Re: Government Regulates Modem Redial Attempts


FYI,

Most countries have a redial limit much less than the FCC's current 15
redial attempts.  For example, Japan has a limit of 2 redials.

Some countries relax that limit somewhat if the redials are spaced a
certain amount of time apart.  You have to check with each country's
regulations to determine that time.

One interesting question is: Does the redial limit apply to ISDN
terminals or just to PSTN modems?  If it does apply to ISDN, does it
apply only to Speech and 3.1 kHz Audio (Voice-band data) calls or does
it also apply to 56/64 kbit/s data calls and multirate (i.e., n x 64
kbit/s) calls?


Hascall H. Sharp Teleos Communications, Inc.
System Engineering 2 Meridian Road
   Eatontown, NJ  07724  USA
voice:  +1 908 544 6424 fax:    +1 908 544 9890
email:   hhs@teleoscom.com

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

From: daveb@jaws (David Breneman)
Subject: Re: GSM and Airbags
Date: 12 May 94 22:43:59 GMT
Organization: Digital Systems International, Redmond WA


Ben Burch (Ben_Burch@wes.mot.com) wrote:

> In article <telecom14.194.6@eecs.nwu.edu> Bill Tighe, bill@noller.com
> writes:

>> ...  Some Audis in the early 80s would respond to RF by having the
>> cruise control go to full throttle while the ABS disabled the brakes!

> Ah, Bill, do you have any pointers to documentation on this?  I
> believe that the causes of the (fatal) Audi "unintended acceleration"
> events have always been in considerable doubt.  Audi claims that it is
> "driver error", since one can always override the throttle with the
> brakes, but since I have seen other cars have a simultaneous brake and
> throttle failure, I have always wondered.

This story is indeed bogus.  The only way ABS could "disable" the
brakes would be if it took out a wrench and unbolted the pedal.  The
infamous unintended accelleration legend is entirely the result of
people pressing down on the gas when they should have been using the
brake.  At least it allowd some people to pick up some really nice
cars cheap when the value of Audis dropped after these scare stories
circulated.


David Breneman                        Email: daveb@jaws.engineering.dgtl.com
System Administrator,                 Voice: 206 881-7544  Fax: 206 556-8033
Product Development Platforms
Digital Systems International, Inc.        Redmond, Washington,  U. S. o' A.

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

From: jfh@netcom.com (Jack Hamilton)
Subject: Re: 3270 Emulation
Organization: NETCOM On-line Communication Services (408 261-4700 guest)
Date: Thu, 12 May 1994 23:00:27 GMT


ssi@winternet.com (Stillwater Systems) wrote:

> I'm looking for a good Shareware 3270 Emulator for Windows. I do a
> great deal of work in the VAX/VMS environment and use WRQ's Reflection
> 2 for Windows, however, this is not suited for the IBM mainframe
> environment. If you know of any 3270 Emulators for Windows, could you
> please provide me with the information I need to obtain them.

Your question really doesn't give enough information.  What are your
options for connecting to the mainframe?

If you can connect through SLIP or PPP or something else that provides
Winsock services, there is at least one tn3270 program available via
ftp from sunsite.unc.edu.  I don't remember the exact path, put it's
comething like micro/pc/winsock.

There are also several books on the market which include the dial-in
only version of NetManage's Chameleon v3.  It's not shareware, but
it's only $25 or so.


Jack Hamilton      Postal: POB 281107 SF CA 94128  USA 
jfh@netcom.com     Packet: kd6ttl@w6pw.#nocal.ca.us.na 

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

From: bill@LIFESCI.UCLA.EDU (William M. Eldridge)
Subject: Re: 3270 Emulation
Date: 12 May 1994 19:42:01 -0700
Organization: UCLA Cognitive Science Research Program


> I'm looking for a good Shareware 3270 Emulator for Windows. I do a
> great deal of work in the VAX/VMS environment and use WRQ's Reflection
> 2 for Windows, however, this is not suited for the IBM mainframe
> environment. If you know of any 3270 Emulators for Windows, could you
> please provide me with the information I need to obtain them.

We've had good luck with McGill's TCP3270.  It's pretty cheap as well
(don't remember the per machine cost, but a site license is something
like $500).  Contact Pierre Goyette (pierre@cc.mcgille.ca).

(Program requires Lan Workplace or Winsock)


Bill Eldridge   bill@lifesci.ucla.edu   310-206-3960 (3987 fax)  

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

Date: Fri, 13 May 94 11:30:12 -0500
From: cohoon@cse.uta.edu (Stephen Cohoon)
Subject: Re: Meeks Defense Fund 
Organization: Computer Science Engineering at the Univ of Texas at Arlington


In article <telecom14.213.9@eecs.nwu.edu> TELECOM Digest Editor notes:

      [Details of net.libel.defendent deleted]

> [TELECOM Digest Editor's Note: ...
      [Moderator's legitimizing deleted]

> The law says no libeling, period. Big corporation, little company,
> single individual, no matter. Newspapers have a little more freedom in
> this respect and all of us have a bit more freedom where politicians
> and 'public figures' are concerned, but no one can deliberatly libel
> another without paying the consequences.

      [More good points from Moderator deleted]

> Inform the net of your situation and plead for funds, but do not give
> us the bit about how the net is so different and special. 
> Now I repeat: it seems a worthy cause otherwise. Lots of netters have
> come to my rescue in the past and I am glad to bring this latest need
> to the attention of our generous readers.   PAT]

This type of request has been showing up more frequently recently.
Someone finds themself in legal trouble and tries to rally the "net"
behind their cause.  Pat's statements are exactly on point.  If you
want the support of the net community then state your case.  Don't
just appeal to our sympathy based on our possession of a modem.  Did
Meeks make libelous statements or not?  What facts support his claim
that he is innocent?  Why should I believe that the people whose names
appear in this posting do in fact support his cause?  In my opinion
this request is suspect at best.  I believe in the value of the net
and moderated digests such as this one.  However, like all the other
forms of media, there are standards of journalism that must be adhered
to or the value of the media will disappear.


Just my opinions,

Stephen Cohoon   cohoon@cse.u ta.ed  


[TELECOM Digest Editor's Note: Well, if the names which appeared in 
the article were there with the permission of the people they represent
(and I doubt the author just picked the names out of the ether and
attached them without permission) then I have no questions about the
authenticity of the appeal. Those are all respected net citizens. But
as you stated, I wish they would realize that merely having a modem and
being connected to the Internet is no longer -- if it ever was -- a
good enough common denominator. Merely publishing an e-journal or
maintaining a mailing list is not a tie that binds either. If anything,
the tie that binds e-journal editors/publishers/list maintainers ought
to be a desire to be treated on a par with the traditional print media,
and that includes the 'right' to get sued once in a while when you flap
your jaw at the wrong time, or when someone gets bent out of shape and
claims that you did. And our objective of course must be to defeat such
suits when they arise, thus my printing of the appeal. Still, some
people are their own worst enemies; that is particularly true on the net. 
PAT]

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

From: cogorno@netcom.com (Steve Cogorno)
Subject: Re: Searching For a Specific Telephone
Date: Fri, 13 May 1994 10:20:32 PDT


Said by: Karim.Farrag

> For quite a while now I'am searching for a specific telephone probably
> manufactured by AT&T.Specific features: narrow receiver, the speech
> unit of the receiver is bent almost 90 degrees; the receiver is shaped
> like an L , wire phone, mostly seen in black colour.I suppose it most
> be a very common model in the US , because I saw in many different
> movies (ex. In the Line of Fire ,Last Action Hero, etc.). Unfortunaly
> AT&T here in Europe wasn't as cooperative as I thought. Now I am
> hoping that someone knows which phone I am talking about (telephone
> manufactor, model number) or maybe the main address of AT&T in the
> US.  Many thanks in advance.

It sounds like you are referring to the MERLIN/System 25,75, etc Voice
Terminals.  You will not be able to use these without a Control Unit,
which will cost more than $1500 in most cases.  The phones themselves
range from $250-500 depending on the size.


Steve  cogorno@netcom.com
#608 Merrill * 200 McLaughlin Drive * Santa Cruz, CA 95064-1015

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

From: Jack Bzoza <JackB@delrina.com>
Subject: Delrina Fax MailBox Retrieval & Class 2 modems
Date: Thu, 12 May 1994 19:15:00 -0400


In a previous message to Jack Bzoza, Clarence Doid said:

>> WinFax 4.0 _requires_ a class 1 Faxmodem for mailbox retrieval.
>> The Class 2 faxmodem that I have cannot be used.

To which Jack Bzoza replied:

> Yes.  you're right.  That is a technical limitation of the hardware as
> 1t elates to the fax protocols. You also need a computer capable of
> running Windows.  I guess you won't be able to use it until you spring
> for $100 for a new modem.

BUT JACK BZOZA WAS WRONG !!

Catherine Murphy, of Delrina's Quality Assurance department advises:

"You may be referring to old information because for Fax MailBox
retreival using WinFax 4.0 Class 2 modems can be used. So can CAS
modem.  Only the remote retrieval is limited only to Class 1 modems.
When the UK version of WinFax with MailBoxes is available it will be
limited only to Class 1 modems. I hope this information is useful."

Sorry for any confusion I may have caused.

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

From: jcm@frank.nccom.com (John Musselman)
Subject: Re: Cellular Call Forwarding
Date: 13 May 1994 04:54:27 -0700
Organization: North County Communications, San Diego, California


Mark W. Earle (mwearle@netcom.com) wrote:

> It should be noted that some roaming costs, though, have dropped in
> the last five months. The per minute charge is lower, and the daily
> fee is not charged. But this is not "universal" you still have to
> check where you intend to roam with the carrier and find out the up to
> the minute info. Of course the roam rate and daily fees (or lack
> thereof) influence greately how and how much the phone is used while
> out of town.

Roaming is still a ridiculous cost! Another thing I stress about: I am
a US West Cellular customer in San Diego. I travel to Phoenix often to
visit friends and family. I wanted to get a Phoenix number to avoid
roaming and take advantage of my dual-nam phone. It was cheaper to go
with Bell Atlantic in Phoenix than it was US West. US West could have
had 1 1/2 times the business from me, however different markets are
differently priced. For people like myself, I would like to see
cellular carriers that are in multiple cities offer a bonus to people
who have multiple numbers in multiple cities ... 


Just my thoughts,
jcm@nccom.com -John C. Musselman -Software Developer/System Analyst

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

From: christos@kuhub.cc.ukans.edu
Subject: Digital MSK Modem Questions
Date: 12 May 94 16:21:08 CDT
Organization: University of Kansas Academic Computing Services


Hello there,

 I have some questions about MSK bit error rate performance.
Going through literature and papers I have encountered a number of MSK
implemenatations and different points of view. I have the following
questions:

1. Do all MSK implemenatations have the same performance? Serial MSK,
Parallel MSK, Fast MSK etc?

2. Parallel MSK is an OQPSK with half sine wave shaping the
transmitted pulse.  Therefore, the Pe (Probability of Error) for MSK
is the same as that for QPSK and BPSK (since Pe for BPSK and QPSK are
the same). MSK can also be viewed as orthogonal BFSK. However, the Pe
for orthogonal BFSK is Q(sqrt(Eb/No)) where the Pe for BPSK is
Q(sqrt(2Eb/No)). Thus, we have two different types of MSK giving
different performances. Is the above correct?

3. Also, in the literature it is mentioned that Serial MSK has a
better performance at higher bit rates? By performance do we mean Pe?
What is the reason for that? Does serial MSK has the same theoretical
performance as the parallel MSK?

4. I have seen in a book, I cannot recall which book was that, that
the PSD of a stationary process tells us about the probability of
occurence of each frequency component. In other words, if the PSD is
large at 1kHz for example then we can say that there is high
probability that the frequency component at 10kHz will occur. Is that
true? The reason that the PSD is a statistical function it should have
some statistical interpretation.

I would very much appreciate your response.


Thanks in advance, 

Chris

Pleaase e-mail: christos@kuhub.cc.ukans.edu

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

From: pworden@weber.ucsd.edu (Pat Worden)
Subject: Request For an FTP Site For X509
Date: 12 May 1994 21:31:35 GMT
Organization: U.C.S.D. Department of Communication


Can anyone send me a name for the site to download X509 protocol
descriptions?

Please send any replies to me a benson@acdca.itt.com. I am borrowing
my wife's account due to a network screwup on my compnay's machine.)


Thanks,

Peter Benson

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

End of TELECOM Digest V14 #222
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