The Information Act the Numbering Crisis in World Zone 1

Total Page:16

File Type:pdf, Size:1020Kb

The Information Act the Numbering Crisis in World Zone 1 The Information Act Brian Hayes Annan, Octopus, 1990 The Numbering Crisis in World Zone 1 i carcity is no stranger in this land of I ten-digit numbers are possible telephone or a ladder without rungs—I couldn't .plenty. From time to time it seems I numbers. Indeed, more than 90 percent fathom the use of it. Then my grand • we are running out of fuel, out of wa of them are unacceptable for one reason mother demonstrated. She picked up the ter, out of housing, out of wilderness, out or another. A telephone number is not receiver and said, "Jenny, get me Mrs. of ozone, out of places to put the rubbish, just an arbitrary sequence of digits, like Wilson, please. Thank you, dear." out of all the stuff we need to make more the serial number on a ticket stub; it has My grandmother's telephone was al rubbish. But who could have guessed, as a surprising amount of structure in it. As a ready quite an anachronism when I first the millennium trundles on to its close, matter of fact, the set of all valid North saw it in the 1950s. Automatic switching that we would be running out of num American telephone numbers constitutes gear—allowing the customer to make a bers? That was one resource everyone a formal language, analogous to a com connection without the help of an opera thought was infinite. puter programming language. When you tor—had been placed in service as early as The numbers in short supply are tele dial a telephone, you are programming 1892. The invention of the first telephone phone numbers. In some parts of the the largest machine on earth, the global switch comes with a story worth telling. United States they are already quite telephone network. According to legend, Almon B. Strowger scarce, and they will have to be carefully A look at the grammatical structure of was a Kansas City undertaker who found conserved over the next few years. At first telephone numbers reveals a lot about he was losing business to a rival. Potential the idea of such a shortage seems prepos how the telephone system works and how customers would telephone Strowger but terous. A standard North American tele it evolved. And modifying that grammar "mistakenly" be connected to his com phone number has ten digits: three for turns out to be the key to solving the petitor. Strowger noted that the competi the area code, three for the central-office numbering crisis. The solution is dis tor's wife was the switchboard operator for code and four for the local line number. A cussed in a document released earlier this the local telephone system. His revenge ten-digit format allows for ten billion dis year by Bellcore, one of the surviving cor was to invent a device that would eventu tinguishable telephone numbers, from porate fragments of the dismembered ally displace operators almost everywhere. 0()()-000-0()00 through 999-999-9999. Bell System. The document has an im Strowger's invention was a ten-posi Even if every person in North America posing title: "North American Number tion rotary selector switch with a pivoting had a telephone at home and at work, as ing Plan Administrator's Proposal on the central arm that could rotate to connect well as separate numbers for a car phone, Future of Numbering in World Zone 1." with any of ten electrical contacts. The a fax machine, a modem and a beeper, pivoting arm was moved by an arrange there would still be more than enough ment of electromagnets, springs and numbers to go around. When diallessI was atelephone boy, my wasgrandmother's an object of ratchets. Each time the electromagnet re The flaw in this analysis is that not all mystery. It was like a clock without hands ceived a pulse of current, it advanced the 12 THE SCIENCES • November!December 1992 arm by one position. In the first network the street? The question is a miniature to do with the operation of the switching to try Strowger's idea, the customer oper version of a problem that has plagued network; instead it was a matter of map ated the switch by pressing a button. If telephone switching for at least forty ping letters to numbers. Central-office you wanted to dial a 7, you pressed a but years. In the first place, KL 5 is simply codes were introduced with names rather ton seven times, thereby sending seven 555; the alphabetic encoding of numbers than numbers because the telephone pulses of current to the electromagnet exists only on the dial of the telephone. company thought IH'tterfield 8 would be driving the selector arm. The push but Thus the first four digits of KL 5-2345 are more memorable than 288. On the tele tons were soon replaced by a rotary dial, the same as the local number 5552. When phone dial, 0 and 1 are not assigned any which automated the counting of pulses. you have dialed those four digits, what alphabetic equivalents, and so they could A single switch of that kind could in should the switch do? Should it connect not appear as the second letter of a cen terconnect ten subscribers. If you were you to your sister, or should it wait to see tral-office name. That subtle constraint, one of those subscribers, when you if you dial more digits? imposed to help avoid confusion between picked up your receiver, your line would The Strowger switch allows little flexi 0 and 0 and between I and 1, has had re be connected to the central selector arm. bility in resolving such ambiguities. It is markably far-reaching consequences for Dialing a one-digit number would then called a step-by-step switch, because once the telephone system. Named exchanges ring one of the other nine telephones. it has made a selection, it cannot go back to are gone, but their influence on the for Adding a second stage of switching could revise the choice. A Strowger switch must mat of telephone numbers remains. expand the service to a hundred sub determine on the basis of the first digit di h'or a long time 0 and 1 were avoided scribers. Now the original switch, instead aled whether to set up a local call or to se even as the third digit of central-office of being connected directly to ten sub lect a trunk line for a call to another ex codes. There was no compelling reason scriber lines, would be linked to a bank of change. If the switch were to establish a for the practice, although again it helped ten more identical switches. Each sub tentative routing to your sister as you di avoid mistaking 0 for O or 1 for I. scriber would be identified by a two-digit aled 5552, there would be no way to undo In any case, for some decades most telephone number. When you dialed the that connection if you continued dialing. North American telephone numbers fol first digit, say a 3, the first selector switch Telephone switching gear has changed lowed a pattern that can be expressed as would connect your line to the selector a great deal since Strowger's time. Mod .V.V.V-.V.V.V.V, where X represents any of arm of the switch leading to lines 30 ern switches are fully electronic rather the eight digits from 2 through 9 and A' is through 39. Dialing a second digit would than electromechanical, and they are ca any decimal digit at all, from 0 through 9. move the selector arm of the second-stage pable of holding a series of digits in a The maximum capacity of this number switch to the appropriate contact. buffer before determining what to do with ing system is equal to 8x8x8x10x1 Ox them. Nevertheless, the architecture of 1 Ox 1 0, or 5,120,000. In practice, it is an telephone numbers is still strongly influ Upper limit that can be approached but not It ingis easy network to see could how abe Strowger expanded switch to enced by decisions made to accommodate reached. A few lines in each central office handle 1,000 lines (with three banks of the peculiarities of early step-by-step are needed for testing and similar purpos switches) or 10,000 lines (with four switches. Moreover, in some rural tele es, and a few exchange codes, such as 555, hanks). In principle, such growth could phone office there may still be a Strowger have traditionally been reserved. More be continued indefinitely, but the quanti switch clanking and clunking away. over, telephone companies try never to fill ty of switching gear would become im a central office completely, since that practicably large. The telephone compa would leave no flexibility when customers ny adopted a different plan. It set up Seven-digitanalysis, dialingto give wouldeach telephoneseem, on direct first move or request a change in service. switching offices that could each accom access to ten million others. Actually, the modate as many as 10,000 subscribers, number of lines available is only about then provided trunk lines to connect the half that. The reason is that some num By to1950 much seven-digit of the I'.S. dialing (though had not spreadto my various offices. At first, calls between cen bers count for more than others. grandmother's house). A telephone con tral offices were completed by operators, "Dial 0 for Operator" has been stan nected to the network had the theoretical but soon that task too was put in the dard telephone practice almost from the potential of reaching five million other hands of the customer.
Recommended publications
  • Historical Perspectives of Development of Antique Analog Telephone Systems Vinayak L
    Review Historical Perspectives of Development of Antique Analog Telephone Systems Vinayak L. Patil Trinity College of Engineering and Research, University of Pune, Pune, India Abstract—Long distance voice communication has been al- ways of great interest to human beings. His untiring efforts and intuition from many years together was responsible for making it to happen to a such advanced stage today. This pa- per describes the development time line of antique telephone systems, which starts from the year 1854 and begins with the very early effort of Antonio Meucci and Alexander Graham magnet core Bell and ends up to the telephone systems just before digiti- Wire 1Coil with permanent Wire 2 zation of entire telecommunication systems. The progress of development of entire antique telephone systems is highlighted in this paper. The coverage is limited to only analog voice communication in a narrow band related to human voice. Diaphragm Keywords—antique telephones, common battery systems, cross- bar switches, PSTN, voice band communication, voice commu- nication, strowger switches. Fig. 1. The details of Meucci’s telephone. 1. Initial Claims and Inventions Since centuries, telecommunications have been of great cally. Due to this idea, many of the scientific community interest to the human beings. One of the dignified per- consider him as one of the inventors of telephone [10]. sonality in the field of telecommunication was Antonio Boursuel used term “make and break” telephone in his Meucci [1]–[7] (born in 1808) who worked relentlessly for work. In 1850, Philip Reis [11]–[13] began work on tele- communication to distant person throughout his life and in- phone.
    [Show full text]
  • Telephonyisdn • LATA • POTS • DLC • LEC 8 ATM • ISDN101 • LATA • POTS • DLC • LEC • ATM • ISDN • LATA • POTS • DLC • LEC • ATM • ISDN • LATA •
    TelephonyISDN • LATA • POTS • DLC • LEC 8 ATM • ISDN101 • LATA • POTS • DLC • LEC • ATM • ISDN • LATA • POTS • DLC • LEC • ATM • ISDN • LATA • A Basic Introduction to How Telephone Services Are Delivered in North America IntroductionISDN • LATA • POTS • DLC • LEC 8 ATM • ISDN • LATA • POTS • DLC • LEC • ATM • ISDN • LATA • POTS • DLC • LEC • ATM • ISDN • LATA • The much touted “convergence” of a range of key communications industries— cable TV, computers, local and long distance telephone service providers, among others—has added myriad new players to the market for telephony services. And, of course, in the thriving telecommunications market, new individuals are joining both established and new telephony companies every day. While the stunning simplicity of the interface to the public switched network— the telephone—largely masks the complexity of the technology from the general public, the public network is, after all, the most massive and sophisticated net- working system ever created. New entrants to the telephony business have an obvious need for a thumbnail introduction to a set of technologies and services that at first can seem daunting in their reach and complexity. Telephony 101 is intended to begin filling this need by providing a basic under- standing of how telephone services are currently delivered in North America. First, it provides a concise overview of the impressive list of revenue-producing ser- Draw on Our Experience vices that make the market so inviting to This book provides your basic begin with. It then provides a basic look at introduction to telephony. But the access, switching, and transmission no beginning course has ever provided all the answers.
    [Show full text]
  • A Data Communications Glossary of Terms
    DOCUMENT RESUME ED 108 612 IR 002 1 -27 AUTHOR Teplitzky, Frank TITLE A'Data Communications Glossary of Terms. INSTITUTION Southwest Regional Laboratory for Educational Research, and Development, Los Alamitos, Calif. REPORT NO SWRL-TN-5-72-09 PUB DATE' 28 Feb 72 NOTE 18p. -EDRS TRICE MF-$0.76 HC-$1.5e PLUS ,POSTAGE DESCRIPTORS Computer Science; Data Processing; *Glossaries; *Media Technology; Programing Languages; *Reference Materials; Research Tools; *Telecommunication ' ABSTRACT General and specialized terms developed in data communications in recent years are listed al abetically and defined. The list is said to be more representative thaexhaustive and is ' intended for use as a reference source. Approximately 140 terms are included. (Author/SK) Gjr ,r ************************************************************A******** Doduments acquired byERIC inclUde =many informal unpublis4e& * * materials not available from other sources. ERIC makes every effort * *.to obtain the best copy c.vpilable. nevertheless, items of marginal * * reproducibility are often enCountered and this,affects the quality * * of the microfiche =and hardcopy reproductionsERIC makes available 4` * =via= the, ERIC Document Re -prod_ uc =tion= Service,(EDRS). EDRS= is not * responsible for the quality of the original document. Reproductions * * supplied =by EDRS are the best that can be made -from= =the original. * ********************************************************************** C I. SOUTHWEST REGIONAL LABORATORY TECHNICAL NOTE DATE: Febr-uary 28, 1972 NO: TN
    [Show full text]
  • Switching Relations: the Rise and Fall of the Norwegian Telecom Industry
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by NORA - Norwegian Open Research Archives Switching Relations The rise and fall of the Norwegian telecom industry by Sverre A. Christensen A dissertation submitted to BI Norwegian School of Management for the Degree of Dr.Oecon Series of Dissertations 2/2006 BI Norwegian School of Management Department of Innovation and Economic Organization Sverre A. Christensen: Switching Relations: The rise and fall of the Norwegian telecom industry © Sverre A. Christensen 2006 Series of Dissertations 2/2006 ISBN: 82 7042 746 2 ISSN: 1502-2099 BI Norwegian School of Management N-0442 Oslo Phone: +47 4641 0000 www.bi.no Printing: Nordberg The dissertation may be ordered from our website www.bi.no (Research - Research Publications) ii Acknowledgements I would like to thank my supervisor Knut Sogner, who has played a crucial role throughout the entire process. Thanks for having confidence and patience with me. A special thanks also to Mats Fridlund, who has been so gracious as to let me use one of his titles for this dissertation, Switching relations. My thanks go also to the staff at the Centre of Business History at the Norwegian School of Management, most particularly Gunhild Ecklund and Dag Ove Skjold who have been of great support during turbulent years. Also in need of mentioning are Harald Rinde, Harald Espeli and Lars Thue for inspiring discussion and com- ments on earlier drafts. The rest at the centre: no one mentioned, no one forgotten. My thanks also go to the Department of Innovation and Economic Organization at the Norwegian School of Management, and Per Ingvar Olsen.
    [Show full text]
  • Direct Distance Dialing
    Chapter 8 Direct Distance Dialing Direct distance dialing of calls nationwide by customers required a major investment in development by the Bell System. Automatic alternate rout­ ing was incorporated into a multilevel hierarchy of switching centers, and a routing plan was developed to allow efficient choice of routes to a toll office in the region of the called telephone. No. 4 crossbar was adapted in several versions to take on the added functions of accepting more dialed digits from customers and of performing more code conversions or translations. The card translator solved the problem of handling the large amounts of infor­ mation required to service calls nationwide, and the crossbar tandem sys­ tem, despite its 2-wire design, was modified extensively for toll service and gave a good account of itself, with 213 toll systems in place by 1968. Crossbar tandem was, in addition, the first host system for centralized automatic message accounting, another important ingredient in making DDD available to all customers, regardless of the type of local office serving them. Selected No. 5 crossbar systems were modified, beginning in 1967, to inaugurate customer-dialing of calls overseas. I. NATIONWIDE PLANNING Initially, much of the equipment used by operators to complete toll calls was of the step-by-step variety, since this system was most suitable for the smaller-size trunk groups and was available, having been developed before World War II (see Chapter 3, section VI). Later, when there was a greater concentration of toll facilities, the No. 4 crossbar was available and was indeed adapted for the larger cities with five post-war installations in New York, Chicago, Boston, Cleveland, and Oakland (see Chapter 4, section III and Chapter 6, section 3.1).
    [Show full text]
  • Account Information High Speed Internet Service *Telephone
    100 Runestone Drive • PO Box 336 Hoffman MN 56339-0336 Office: (320) 986-2013 • Fax: (320) 986-2050 www.runestone.net • [email protected] Account Information Name of Applicant: Service Address: Billing Address (if different): City, State, Zip: City, State, Zip: Daytime Phone Number: Additional Contact Number(s): Current e-mail Address: If a business, check appropriate box: Individual/Sole Proprietor Corporation Partnership Other:_________________ I rent my home/apartment (Written permission from owner must be received in our office before wiring or outlets are done) Account Password (Required): This will keep your account secure and not allow anyone who is not authorized to request or receive information about your account Additional Authorized Contact(s): Please list any additional contacts you would like to have access to information about or make changes to your account High Speed Internet Service Prices subject to change • Services are subject to availability 10 - 15 Mbps….$76.95 40 - 50 Mbps.... $89.95 250 - 300 Mbps…$145.95* 20 - 30 Mbps….$81.95 75 - 100 Mbps...$120.95 500 - 1000 Mbps..$169.95* I would like to lease a Managed Wi-Fi Router…$3.95 per month *This speed not available to wireless customers Desired Runestone email addresses (optional): _______________________________ @runestone.net Email address requirements: Minimum 3 characters, lower case only, no special characters Customers are allowed up to 5 email addresses. Please contact our Internet Department for additional email setup. Desired Email Password: ______________________________________________________ Password requirements: 16 to 80 characters, including one from each of these groups: (a-z) (A-Z) (0-9) (~@#$*( ) = -) *Telephone Service Prices subject to change • Must have Internet to have Telephone Service.
    [Show full text]
  • BEGINNINGS of AUTOMATIC TELEPHONY Part II Only a Very Few
    60 BEGINNINGS OF AUTOMATIC TELEPHONY Part II Only a very few engineers who are fascinated flattened out, drowned in the anonymous not only by the future development of tele­ mass of fellow~engineers. There is no longer phony, but also by its past history, still find any question of anyone leaving a personal it worth while to contemplate and try to under­ stamp on a product or system, which will be stand the vestiges of the early days of electro­ known only by a trade name or even by a mere mechanics. symbol followed by a serial number. No museum has so far engaged in the syste­ matic collection ofthese souvenirs of the past, 1.5.2. Things were different in the 1890s. In except for a few parts or models which have an area which was as yet unexplored and had . been saved from destruction and are scattered no precedents, an inventor could give free rein among various national telecommunication to his imagination and could dream of suc­ museums. Nor is there any detailed mono­ cess. Relatively small resources were required, graph on the subject which would show the but a great deal of ingenuity and very often diversity of designs. Such a work would re­ cooperation which began within the family quire long and patient research and, if it were itself: ever undertaken, it would certainly have to "Brothers and other relatives working to­ 4 mention three fundamental references ): gether were not unusual. The brothers Con­ -the article by P.C. Smith which appeared in nolly are only one example.
    [Show full text]
  • Listing of Various Vintage Switching, Telecom, and Teletype Tools, Part 1
    C.O. and Strowger Switch/Other Telecom Tools Part 1 Etelco BT The following are some of the tools in the collection of the Telephone Museum of P.E.I. - they are not for sale. I am posting this on the site, as it provides a good listing of the tools available from each manufacturer, plus descriptions of the designed usage from the manufacturer's catalogs. This is by no means a complete listing of all tools manufactured and used in the telecom industry. There was a specialty tool designed for just about every job. You may note some items marked as not yet received. These are items on order, or that are in the mail to me. I am continually looking for tools to add to this collection - Dave Hunter, [email protected]: I have only listed a few of the Butt sets in the collection. I have 20-30 in the collection, but have only listed a few of the more common types. I have a number which were conversions of non-dial butt sets which have had dial shrouds added as well. The early items I put on this list do not have accompanying photos. Recent additions do have photos, and as I get time, I will gradually re-vamp the listing to include photos for all items listed. The latest versions of these files may be downloaded from: Part 1: http://www.islandregister.com/phones/tools_switching.pdf Part 2: http://www.islandregister.com/phones/tools_switching2.pdf WE/NE/Bell C.O. Tools: NE-1014B - Aug 22, 2012 - This is a 1014B donated by Barry McCallum and was a kit which included the NE-20B case, an NE715A tool, NE 716A tool, NE716B tool, NE717B tool, 1 Box containing four NE 718A tools, Container containing eight P12B536 tubes, NE 666B tool, NE 674 tool, and a container holding one NE 689A contact separator.
    [Show full text]
  • Feature Document International Direct Distance Dialing (Iddd) No. 3 Electronic Switching System
    BELL SYSTEM PRACTICES SECTION 233-190-503 AT&TCo SPCS Issue 1, March 1980 FEATURE DOCUMENT INTERNATIONAL DIRECT DISTANCE DIALING (IDDD) NO. 3 ELECTRONIC SWITCHING SYSTEM CONTENTS PAGE CONTENTS PAGE 9. INSTALLATION/ADDITION/DELETION .. dd INTRODUCTION ........ 3 10. HARDWARE REQUIREMENTS 2. oe we) (6d 1. GENERAL INFORMATION ..... 3 11. SOFTWARE REQUIREMENTS woe ew we UT 2. DEFINITION eee ee ee 3 12. DATA ASSIGNMENTS AND RECORDS . DESCRIPTION ........ 3 13. TESTING woe ee we ee wwe Cd 3. USER OPERATION woe ee ee 3 14. OTHER PLANNING TOPICS re 4. SYSTEM OPERATION , oe ee ee 4 ADMINISTRATION ...... 12 CHARACTERISTICS - ee ee 15. MEASUREMENTS se ew we ew wee) CT 5. FEATURE ASSIGNMENT woe ee 9 16. CHARGING woe ee ew ww ew OT 6. LIMITATIONS woe ee ee ww we) (10 7. INTERACTIONS woe oe ee ew ee 0 SUPPLEMENTARY INFORMATION 12 8. RESTRICTION CAPABILITY ~ ee ew. 7 17. GLOSSARY woe ew we ww we) Od INCORPORATION INTO SYSTEM 11 18. REFERENCES woe ee we we ww NOTICE Not for use or disclosure outside the Bell System except under written agreement Printed in U.S.A. Page 1 SECTION 233-190-503 Figures Tables CONTENTS PAGE CONTENTS PAGE 1. IDDD Flowchart 5 A. Country Codes and National Numbers 4 2. IDDD Translator 7 B. Summary of Outpulsing to TSPS . 10 C. Frequencies for MF Pulsing (in Hertz) 10 Page 2 ISS 1, SECTION 233-190-503 INTRODUCTION When 01 is followed by a “0” (representing an international 0- call), the call is intended for the 1. GENERAL INFORMATION overseas operator. A_ station-to-station call is identified by the prefix “011.” When the prefix 1.01 This document describes the International “01” is followed by the first digit of the country Direct Distance Dialing (IDDD) feature for code (representing an international 0+ call), the the No.
    [Show full text]
  • End-To-End Detection of Caller ID Spoofing Attacks
    End-to-End Detection of Caller ID Spoofing Attacks Hossen Mustafa, Member, IEEE, Wenyuan Xu, Member, IEEE Ahmad-Reza Sadeghi, Member, IEEE and Steffen Schulz Abstract—Caller ID (caller identification) is a service provided by telephone operators where the phone number and/or the name of the caller is transmitted to inform the callee who is calling. Today, most people trust the caller ID information and some banks even use Caller ID to authenticate customers. However, with the proliferation of smartphones and VoIP, it is easy to spoof caller ID information by installing a particular application on the smartphone or by using service providers that offer Caller ID spoofing. As the phone network is fragmented between countries and companies and upgrades of old hardware is costly, no mechanism is available today to let end-users easily detect Caller ID spoofing attacks. In this article, we propose a new approach of using end-to-end caller ID verification schemes that leverage features of the existing phone network infrastructure (CallerDec). We design an SMS-based and a timing-based version of CallerDec that works with existing combinations of landlines, cellular and VoIP networks and can be deployed at the liberty of the users. We implemented both CallerDec schemes as an App for Android-based phones and validated their effectiveness in detecting spoofing attacks in various scenarios. Index Terms—End-user Security; Caller ID Spoofing; ! 1INTRODUCTION the US government passed the legislation Truth in Caller ID Act of 2009 [5] making it illegal to transmit “What’s worse than a bad authentication system? misleading or inaccurate caller ID information with A bad authentication system that people have the intent to defraud.
    [Show full text]
  • Innovation Is in Ourdna Letter from Our Contents Page 12 Our Editor Features
    Magazine for the Science & Technology Innovation Center in Middletown, NJ • Premier Edition Honoring the Past, Creating the Future Innovation is in ourDNA Letter from Our Contents page 12 our Editor Features 2 The History of AT&T 94 Data Transmssion — Fax Welcome to our Science & Technology Innovation Center of Middletown, New Jersey magazine premier edition. The new Innovation Center is a place 12 The Transistor 100 Cellular Phones of inspiration and learning from the history of AT&T and significant inventions that our company has created over the past 142+ years that contribute to 13 Bell Solar Cell 104 Project AirGig™ the advancement of humanity. Over my years at AT&T, I have spoken to many The Telstar Project Our Contributors people who never knew that AT&T had a history of innovation in so many 16 109 areas beyond the creation of the telephone by Alexander Graham Bell. Coax Cable 24 Throughout the years, AT&T has been a key player in local and long-distance 30 Fiber Optics in the AT&T Network voice telephony, motion pictures, computers, the cable industry, wireless, and Science & Technology broadband. AT&T has served the nation’s telecommunication needs and par- 34 Vitaphone and Western Electric ticipated in many technology partnerships in every industry throughout the globe. The breadth of technology and innovation goes on and on, but a 44 Picturephone Irwin Gerszberg few of the innovations you might see at our new Innovation Center include: Innovation ground-to-air radio telephony, motion picture sound, the Telstar satellite, Theseus Honoring the Past, Creating the Future AVP Advanced Technology Research 48 telephone switching, the facsimile machine, military radar systems, the AT&T Science & Technology transistor, undersea cable, fiber communications, Picturephone via T1’s, coin 50 A Short History of UNIX™ EDITOR-IN-CHIEF Innovation Center phones, touch-tone dialing, AMPS cellular phones, UNIX™ and C language Irwin Gerszberg programming.
    [Show full text]
  • Mcimetro Access Transmission Services Corp. IL C.C. Tariff No. 1 D/B/A Verizon Access Transmission Services Original Page No
    MCImetro Access Transmission Services Corp. IL C.C. Tariff No. 1 d/b/a Verizon Access Transmission Services Original Page No. 42 ACCESS SERVICES 5. SWITCHED ACCESS SERVICE 5.1 General Switched Access Service, which is available to Customers for their use in furnishing their services to End Users, provides a two-point communications path between a Customer's Premises and an End User's Premises. It provides for the use of common terminating, switching and transport facilities. Switched Access Service provides the ability to originate calls from an End User's Premises to a Customer's Premises, and to terminate calls from a Customer's Premises location to an End User's Premises. Rates and charges are set forth in Section 7.6. The application of rates for Switched Access Service is described in Section 7.4. 5.2 Provision and Description of Switched Access Service Arrangements Switched Access Service is provided in the following service type: 5.2.1 Feature Group D (FGD) Access FGD Access, which is available to all Customers, is provisioned at the DS1 level and provides trunk-side access to Company Local Switching Center switches, with an associated uniform 10XXX Access Code for the Customer's use in originating and terminating communications. Basic FGD service will be provided with Multi-Frequency In Band Signaling (SS7 is also available as a Common Switching Option for Feature Group D). In addition, Conventional Signaling for direct Carrier Trunk groups is available at the Customer's option. End Users of the Customer's service may also originate calls to certain FGD Access Customers without dialing the 10XXX Access Code if the End User is presubscribed, as described herein.
    [Show full text]