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Aucbvax.2840 fa.telecom utzoo!decvax!ucbvax!telecom Thu Aug 27 22:08:38 1981 TELECOM Digest V1 #4 >From JSol@RUTGERS Thu Aug 27 22:01:17 1981 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 ----------------------------------------------------------------------

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 BERKELEY AT>

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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