TELECOM Digest V1 #4
ucbvax!telecom
TELECOM AM Digest Friday, 28 Aug 1981 Volume 1 : Issue 4
Today's Topics: Administrivia - Distribution Problems
World Numbering Plans - IDDD
Who Said Centrex Doesn't Crash
Dial Your Own Credit Card Calls - A Reality
Working While flying - Airborne Phones Coming
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Date: 28 Aug 1981 0028-EDT
From: The Moderator <JSol at Rutgers>
Subject: Administrivia
We're experiencing some technical difficulties sending out the
digest each day. According to my calculations, TELECOM V1 #2 did
not fully reach many of the recipients. This is unfortunately not
something I can easily track down, and with so many parts of software
all around the network, a solution is not quick in coming.
Please bear with me as I try to find the offensive peice of hardware
or software; and send mail to TELECOM-REQUEST asking for another copy
of the issue if you don't see the proper "End of .." message at the
end of the digest.
Enjoy,
JSol
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Date: 27 Aug 1981 1125-EDT
From: John R. Covert <RSX-DEV at DEC-MARLBORO>
Subject: More details on IDDD and World Numbering Plans
Lauren already explained some of this, but here is some more detail:
In the U.S. and Canada, we place IDDD calls by dialling the prefix 011
for station-to-station calls and the prefix 01 for operator assisted
or credit card calls (the "or" because beginning in Decem- ber, in
many areas, you will be able to dial your credit card number -- it
won't change the rate; you'll still pay operator assisted rates). 01
is only implemented in those areas where your operator service comes
from a TSPS (or equivalent, such as TOPS) running the appropriate
release of the software.
What follows next is the country code. The first digit of the country
code is the World Numbering Zone. There are eight World Numbering
Zones:
1 - The U.S., Canada, St. Pierre & Miquelon, and some of the
Carribean (the part in area code 809).
2 - Africa
3&4 - Europe, excluding the USSR
5 - Mexico, Central & South America, and the rest of the
Carribean
6 - Australia, some of SE Asia, and the Pacific Islands
7 - The USSR
8 - Japan, China, and nearby parts of SE Asia
9 - India and the Middle East.
With the exception of Integrated Numbering Zone 1 and the USSR, all
country codes are two or three digits.
The country code is followed by whatever is dialed within the country
(minus access codes such as "1", "0", "16"). These sometimes are
called Area Codes (U.S., Canada, U.K.) (yes, the UK no longer calls
them STD - Subscriber Trunk Dialling Codes) and are sometimes called
city routing codes. In some places (e.g. Belize, Costa Rica, El Sal-
vador, Fiji, Guam, Honduras, Kuwait, Luxembourg, Papua New Guinea,
Qatar, Singapore, and Tahiti) no city code is required. There are a
few strange cases, for example Bogota, Colombia, where no city code is
required, although one is required for Barranquilla. Then there are
the countries who don't have their own phone system and are just city
codes within another country (e.g. Andorra and Monaco (via France),
Liechtenstein (via Switzerland)).
Parsing this even causes the telephone company's billing systems
problems at times. At the present time, calls to Paris are showing up
on some Washington, D. C. customers bills as calls to Andorra.
The length of the city code varies in length, even within the same
country. For example, London is 1 whereas Sliddery is 77087.
The local telephone number varies in length, even within the same
city.
The maximum length number we can dial from the U.S. and Canada is
12 digits, not counting the access code. This prevents us from
dialing a few places, for example, a number at Patch Barracks,
(EUCOM HQ), Stuttgart-Vaihingen, Germany, might be +49 711 7301 2345,
one digit too long for us to dial. We can call the post information
operator, at +49 711 7301 92.
Some countries have fixed length numbers, such as Belgium, France,
Spain, Norway, Peru, Colombia, Turkey, and some others. This may
mean that the TOTAL number (city code plus local number) is fixed
length. For example, Paris is +33 1 555 2368, (a total of 10 digits)
Cannes is +33 93 55 2368 (same total).
Some types of exchanges keep track of what is legal in each country.
For example, No. 1 ESS knows whether a country has fixed length or
variable length numbers, and the minimum. No. 2 ESS knows both the
maximum and the minimum. TSPS can only handle certain cases, for
example, you can't represent 8-fixed, so you have to tell it
8-minimum.
When this changes (as it did in Belgium a few years ago) EACH central
office has to be updated. When this happened, I was living in
Atlanta, and my exchange had not been updated. Even the phone company
didn't understand how their equipment worked. When I told them how to
fix it, they insisted that the 011 was all that the local office
looked at. It took over three weeks to convince them, during which
time about half the exchanges in Atlanta couldn't call Belgium. On
July 18th of this year, Libya changed from fixed length numbers 10
digits long to numbers either 10 or 11 digits long. It may be years
before it works correctly everywhere.
Also note the standard format for representing a phone number. On
your business cards, you should put your number as follows:
National (311) 555-2368
Telephone ------------------------------
International +1 311 555 2368
Note that in the international version of the number, you put a "+" to
indicate that the local international access code is to be dialled,
and you DO NOT put any dashes or other punctuation (other than spaces)
in the number itself, since these may have a special meaning in some
countries. For example, in West Germany, the "-" is placed between
the prefix and the extension in a PBX with DID. You are told that to
reach the attendant, drop all digits of the extension, and dial a "1"
in its place.
International Calls are sent out in different manners depending on
the type of local office from which you are originating the call.
In Step-by-step offices, the action of dialing "0" connects you
directly to your local TSPS (if that is what provides operator service
in your area). The remainder of the digits are collected and
interpreted by the TSPS. Note that some Step-by-step offices have
been converted to handle touch-tone by the addition of a set of
crossbar registers across the line finders. These registers do not
have the capacity to handle the long IDDD numbers. In one case
(404-373, Decatur, Georgia) the TSPS was instructed to deny IDDD
service even to the rotary dial customers in the office, be- cause it
didn't make sense to tell customers that they now could dial IDDD if
they had rotary dials, but not if they had Touch-Tone. (404-373 has
since been convertedd to ESS.) If your SXS office does its Touch-Tone
to rotary conversion with other equipment, this re- striction may not
exist.
In the few No 5 X-Bar systems which have IDDD, the signalling scheme
will depend on when it was implemented. In New York City, there are
some #5 X-Bars which were the first COs in the country to have IDDD.
They do the dual stage outpulsing Lauren described (first outpulse
the code to reach an appropriate overseas "sender", then outpulse
the overseas telephone number), without going through TSPS. (At the
time these COs were given IDDD, TSPS didn't even exist; there was a
thing called TSP, but it never was able to handle IDDD.) In that
system, you were often restricted to 11, rather than 12 digits.
This change to No. 5 X-Bar is very expensive, and is no longer being
done. It is now possible for a No. 5 X-bar to send the call to TSPS
and allow the TSPS to do the dual stage outpulsing. It is interesting
to note that the "#" does not work in some No. 5s -- use of it causes
your call to fail. (This is the case in 613-592 in Ontario.) Very
few No. 5 X-Bars in the U. S. have been converted to handle IDDD.
In most No. 1 ESS systems, the ESS does the dual stage outpulsing.
The exception to this is Connecticutt, where the calls are often sent
to TSPS. I have been told that AT&T frowns on this. As a caller, I
would, too, because it means going through an extra machine, affecting
transmission quality.
In all No. 2 ESS systems I have seen, TSPS does the dual stage
outpulsing.
Eventually, CCIS (Common Channel Interoffice Signalling), which can
carry more information in a single message than is possible in the
maximum MF message sent by existing equipment, will eliminate the need
for dual-stage outpulsing.
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Date: 27 Aug 1981 1134-EDT
From: John R. Covert <RSX-DEV at DEC-MARLBORO>
Subject: CENTREXs don't crash, you say...
CENTREXs served by No. 1 ESS don't crash extremely often, but when
they do, the results can be spectacular. In Nashua, NH, the No. 1 ESS
providing both CENTREX service to various companies in the area and
local service to most of Nashua and Hudson was down for about two
hours a few weeks ago, making it impossible for companies to conduct
business or for anyone to contact the local fire department or police.
We have also seen our CENTREX crash without any affect on the local
town. Once the first digit interpreter table got wiped out (which is,
of course, separate for the CENTREX and the town). We could get
incoming calls, but the CENTREX refused to accept any first digit
dialed by anyone.
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Date: 27 Aug 1981 0854-PDT
Sender: WMARTIN at OFFICE-3
Subject: Centrex and switchhooks
From: WMartin at Office-3 (Will Martin)
I was a bit surprised by Andy's comment regarding Centrex: "I never
had to worry about how long I depressed the switchhook." We went to
Centrex a few months ago and I have been irritated and annoyed at the
necessity of pressing the switchhook a certain amount of time in order
to simply do the normal task of terminating the connection or
returning to the normal dial tone. I seem to constantly be getting the
multiple beeps and the secondary dial tone instead of just ending and
getting back to the base level. It seems subjectively to be taking
longer and longer as the months go on! Every time it happens I am
irked. I think it is a big mistake to use a function previously
reserved for one simple and basic action (hanging up) and add other
tasks to be performed by that action but dependent on some variable
like timing. Why couldn't the functions be implemented using
touch-tone commands? I gather from the Dimension discussions that it
is far worse in this area, requiring different timing estimates by the
user to get to different functions? Yuck!
Back to the hand cranks!
Will Martin
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Date: 27 Aug 1981 1712-EDT
From: John R. Covert <RSX-DEV at DEC-MARLBORO>
Subject: Dialing your credit card yourself
In Jacksonville, Buffalo, St. Louis, and eventually everywhere, a new
system is being implemented which allows you to dial your credit card
yourself. This system, provided by TSPS, used to be called Auto Bill
Calling, but is now called Calling Card Service. (Bell may start
calling their billing cards "Calling Cards" rather than "Credit Cards"
since they really aren't credit cards.)
At TSPS there is a data base which determines which telephones have
the service. Different answers are given as to whether it will be
enabled for all phones or only for pay phones and Charge-a-calls.
You dial a 0+ call in the normal manner. Once the call reaches TSPS,
if the phone from which the call is being placed is enabled, you will
hear 941+1477 Hz (the touch-tone "#") followed by fading 350+440 Hz
(dial tone). The "#" is to disable any touch-tone to rotary converter
which may be on the line.
You will then get the message, "Please dial your card number or zero
for an operator now." If you dial 0 or let it time out (no, "#" is
not used for timeout in this case) you will reach an operator. If
not, your call is a station-to-station call billed to your card. Any
time the distant end is "on-hook" (either before answering or after
it hangs up) you may depress the "#" key, to which you will be told,
"You may dial another number now." This is billed to the same card
previously entered.
You are still be charged the operator assisted rate, although this may
change in the future. (In Massachusetts, for intrastate calls, all
credit card calls are now surcharged only 45 cents, much less than the
operator assisted surcharge made when an operator does a collect or
third-number billing call for you. This may be the model for eventual
nationwide implementation. In New Brunswick, there is no surcharge
for credit card calls within the province. I think you have to have a
New Brunswick credit card. I'm kicking myself now for not placing a
call while I was there to find out!)
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Date: 27 Aug 1981 1743-PDT
From: Zellich at OFFICE-3 (Rich Zellich)
Subject: Working while flying - airborne phones coming
To: HUMAN-NETS at MIT-AI, WORKS at MIT-AI
>From the 26 Aug 81 issue of MIS Week newspaper:
W.U. TO ACQUIRE 50% OF AIRFONE
Upper Saddle River, N.J.
- Western Union Corp. said last week it has agreed to acquire a 50
percent interest in a new communications system, owned by Airfone
Inc., that will allow passengers on commercial airlines to place a
telephone call while in flight.
According to Western Union, Airfone has received a developmental
license from the Federal Communications Commission (FCC) to provide a
nationwide, fully automatic air-to-ground radio telephone
communications service.
Initially, Western Union said, service will be provided through air-
to-ground telephones installed in wide-bodied aircraft, which in turn
will be linked with multiple ground stations providing coast-to-coast
coverage. It said a passenger would be able to place a call by using
portable telephones located in various sections of the aircraft.
The system, it said, is expected to be operational during the second
half of next year.
---
Wonder if I'll be able to use my TI745 with this service...or better
yet, the still-to-come portable CRT connected to my still-to-come
stand-alone home workstation? -Rich Zellich
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Mail-from: MIT-AI rcvd at 27-Aug-81 2111-EDT
Date: 27 Aug 1981 17:47:36-PDT
From: telecom-link at Berkeley
In real life: Steven M. Bellovin, U. of North Carolina at Chapel Hill
Subject: direct-dial credit card calls
There certainly are plans for it; about two years ago, the phone
company changed the format of their credit card numbers to 14 digits
(from a shorter string containing alphanumerics) specifically to
pave the way for direct dialing. I don't know that service will
be available from ordinary phones, or only the special "Charge-a-Call"
phones in the airports, etc.
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Date: 26 Aug 1981 15:57:10-PDT
From: decvax!duke!unc!smb at Berkeley
Reply-to: "decvax!duke!unc!smb in care of" <CSVAX.Telecom-Link at Berkeley>
In real life: Steven M. Bellovin, U. of North Carolina at Chapel Hill
Subject: Dimension PBXen
Any reason why they couldn't (can't) hang a simple speech synthesizer
on the lines rather than noisemakers? If nothing else, I'm SURE that
TI would sell them a few "Speak 'n' Spells".
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End of TELECOM Digest
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