The Old Private Line Newsletter, Number 5, April 15th to May 1, 1999
Introduction
Greetings. I hope you are all well. I've been productive the last two weeks. I divided the telephone history series into seven parts which makes each page quicker to load.And I've been double checking sources for the series, thinking about a timeline for it as well, casting about for a search engine for TelecomWriting.com, and working on the much delayed "One page guide to wireless." I also got all TelecomWriting.com files local and even used AltaVista's Bablefish to translate my cellular basics file into Spanish.
I. I Get Letters
I READ SOMEWHERE SOMETHING ABOUT A MAN NAMED ANTONIO MEUCCI WHO WAS BORN IN FLORENCE AND EMIGRATED TO STATEN ISLAND WHO MADE A WORKING TELEPHONE IN 1857. DO YOU NOW OF THIS PERSON AND THE CLAIMS MADE ABOUT HIM ?
Many people claim to have invented the telephone but Bell's claim is well documented. Nearly every scholar agrees that Bell and Watson were the first to transmit intelligible speech by electrical means. Others transmitted a sound or a click or a buzz but our boys were the first to transmit speech one could understand. I did a cursory look for materials at UC Davis the other day on Meucci but I did not find anything. Anyone knowing more can e-mail me:
Dear Tom:
After reading some of your info I see that I can't reprogram my first cell phone, which was a Radio Shack bag phone, so that I could use my US Cellular in my car and my old phone @ home. Is that true? You can't program an old phone to your existing cell phone number?
You _could_ program both phones to the same telephone number or Mobile Identification Number. But since each phone has a unique Electronic Serial Number or ESN it wouldn't do you any good. The cellular carrier would key on the ESN and reject the call if the ESN was not assigned an account.
The carrier wants an individual account for each and every phone. That's how they get an additional monthly charge off the tens of millions of people who would like exactly what you want. Like a husband and wife who want to share a single number. They'd pay for all charges made to a single number. But the carrier would loose out on that additional monthly charge. And that is exactly what, in part, drove people to cloning.
By comparison, handsets in GSM or PCS are anonymous; it's the memory module or SIM that confers individuality. I sympathize with your plight but the CTIA along with the Secret Service has made your simple wish a federal crime. Sorry for the bad news. A low cost companion plan is your only hope.
Hello, Tom:
Do you have any information on the different cellular types (CDMA, TDMA, PCS, GSM) etc. and their level of security regarding eavesdropping?
Analog offers the least security. Many scanners, test equipment, and even modified cell phones let you listen to calls. D-AMPS or IS-54, the digital TDMA system used throughout the country, offers more security. Calls are multiplexed and thus scrambled together. They're tougher to take separate and listen to. But you can be dropped off an digital channel when your call started on analog channel. So be careful.
IS-136 TDMA systems like AT&T are fairly secure due to multiplexing but, again, in outlying areas a TDMA cellular plan will default to analog if it can't find its preferred digital signal. Really worried? Most cell phones can be equipped with accessory units that encrypt the voice traffic:
GSM and PCS1900 are far harder to eavesdrop on, beyond the capability of most scanners and radio hobbyists. In these two systems the voice traffic is multiplexed and encrypted. A CDMA based PCS signal is probably the toughest to break down, since the voice traffic is encrypted and the signal is transmitted as scattered bits thrown all over the spectrum.
No matter what, a properly equipped cellular technician, someone with all the right tools for maintaining a cell site, and with access to the base station or switch, can certainly intercept a signal if properly motivated. But that is subterfuge at a very high level. And there is no guarantee the call won't be intercepted once the call is on the landline network. So those needing a secure communication link from end to end should consider products from a company like Transcrypt.
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II. Cell Basics Article Correction
Dwayne Rosenburgh (N3BJM) sends in these two important corrections to the cellular basics article:
"In the section 'The SAT, you state 'You don't hear it since the signal lasts less than 300 ms. and because it's muted during transmission. " The fact that the signal lasts just 300 ms has nothing to do with why you don't hear the SAT. In fact you can hear tones/signals of less than 300 ms. Perhaps you should say 'You don't hear it since the signal is muted during transmission.'
In the next paragraph, you state 'The signaling tone is a very high audio frequency tone that you can't hear. Maybe your dog can but not you. It's 10kHz tone.' Well, humans can hear from 20 Hz - 20 kHz. So, the reason that we cannot hear the ST is not due to its frequency."
Dwanyne is correct on both points and I've accordingly revised both the English and Spanish versions of the basics article:
http://www.TelecomWriting.com/Cellbasics/Cellbasics.html
Please, please please -- if you have any corrections or comments with any of my writing please send it in and I will look at it. My goal is to put out the most accurate information I can, and it's only with your help that I can do it.
III. More Outside Plant Information
Matthew Sadler (KF4LHP), of the Coaxial & Microwave Telephone Page http://www.qsl.net/kf4lhp/telco/index.html, sent in this great URL for looking up OSP information:
http://www.relteccorp.com/d0000004.cfm
Link now dead!:-( April 21, 2001
This company produces all sorts of cabinets, pedestals, and splice cases. Their enormous catalog of PDF files give plenty of names and photographs to identify OSP equipment. They have so many photographs, in fact, that it would make a great base for building a site featuring telephone infrastructure. Any one up to doing that?
And Something From Me
Interested in Outside Plant? Tried to explain the local loop to someone with a minimum of confusion? I've put up a small article with six or seven illustrations that quickly points out the basic elements. Kind of neat.
http://www.TelecomWriting.com/OSP/No.html
IV. Central Office Stuff
Agent Steal comes in from the cold -- Central Office Ops
Agent Steal, aka Justin Petersen, recently e-mailed me. His article "Central Office Operations" originally written for the LOD's Technical Journal and then published in the Winter 1990 issue of 2600, helped me greatly in writing many of my own articles. Although circa 1990, it represents a good, clearly written description of central office operations at that time. Check it out at:
http://zbone.com/justin/lod4.txt
Link now dead!:-( April 21, 2001)
And even more CO material
A great central office site. Features photos of step, panel, and crossbar central office switches. And even a 5ESS since Ken works in a C.O. with a 5. And there's a mail list you can join to keep up to date on all this old but wonderful technology:
http://www.freeyellow.com:8080/members4/thecentraloffice/
Link now dead!:-( April 21, 2001)
V. A Free Fax Number
Don't have a fax machine? Still need to get faxes? Read on . . .
Have you heard about .efax.com? They provide a free telephone number for people to send you faxes. People send the fax to your number. You get the fax in your e-mail as a file that you view as an attachment. In the case of a Macintosh they send you a .tiff file of the page. Tell people, by the way, to send in the highest resolution. efax.com doesn't ask you for a home address or a home phone number. Just your zip code and a valid e-mail address. You can't send faxes yet and your fax number might be in another area code (mine is in the 707 and not the 916) but is free and it does make getting faxes possible for people who don't want to buy a machine or get another line for one.
VI. Who Made The First Cell Phone?
People keep asking me who made the first cellular telephone and when. The first telephones using the cellular concept were payphones installed by the Bell System aboard a train. The first handheld units were possibly developed by Motorola, although they do not take credit.
http://www.mot.com/General/Timeline/
I'd also like to know who made the first commercial unit. Anyone got a make and model number? I will probably put the question up at alt.cellular.
VII. Lucent Comes Through For Telephone History
John E. Donovan, editor of Bell Labs Technology, has arranged permission for me to put several key cellular articles on line. These articles helped me write my recent radio-telephone and cellular history piece. Once I get these AT&T Bell Laboratories Record articles scanned, you can read and research them yourself. I'll note the page breaks so you can cite the articles correctly. Here's a list of what's coming and why they are important:
1. "Telephone Service for St. Louis Vehicles." Bell Laboratories Record July, 1946. (The Bell System introduces commercial vehicle radio-telephony, called MTS.)
2. Peterson, A.C., Jr. "Vehicle Radiotelephony Becomes a Bell System Practice." Bell Laboratories Record April, 1947 (Re-caps the Saint Louis experience and adds more details.)
3. Douglas, V.A. "The MJ Mobile Radio Telephone System." Bell Laboratories Record December, 1964 (Introduces IMTS or Improved Mobile Telephone Service, with full duplex working and automatic dialing.)
4. Paul, C.E. "Telephones Aboard the 'Metroliner'." Bell Laboratories Record March, 1969 (Frequency reuse, the most important cellular concept, is introduced.)
5. Young, W.R. "Advanced Mobile Phone Service: Introduction, Background, and Objectives." Bell System Technical Journal January, 1979. (I'll reprint the first chapter of the article that introduced cellular.)
It will take me a while to scan the documents, clean them up, and put them into HTML, but things are now on track. I think every cellular history enthusiast should be happy that Lucent has graciously given permission to put these articles on line.
VIII. Learn Telephony With These Great Tutorials
Check out this page for -- easy to read telephone tutorials:
NT's Telephony 101 is especially good. Click here to download the .pdf file from my site. (internal link)
And here's another URL for more tutorials. The best wireless writing on the web. They're all in HTML or .pdf format:
http://www.webproforum.com/wpf_communications.html Dead link
IX. Wireless Transmission
Most of Monday spent writing on transmission for the digital wireless article. Came up with just nine or ten paragraphs for my effort. Here's some of it below the URL:
http://www.TelecomWriting.com/PCS/Multiplexing.htm
Transmission in telephony means sending information on electricity or light from one point to another. There's two things involved: the information itself and the equipment sending it. Voice, data, signals, or other messages make up a transmission. Wires, cable, or radio waves make up the transmission media, the technology or device carrying the information. Using a railroad analogy, electricity is the boxcar that carries the information and radio waves are the track electricity rides on.
D. Transmitting information
Wireless systems use many ways to transmit information. Here are some:
1. Frequency division multiplex or FDM, used in analog cellular;
2. Time division multiple access or TDMA, used in digital cellular and PCS;
3. Code division multiple access or CDMA, used mostly for PCS.
No transmission scheme stands by itself, that is, these techniques are not by themselves operating systems. They are part of one. When someone asks, "Is D-AMPS or digital AMPS TDMA?" they usually mean, or should mean, "Is D-AMPS TDMA based?" The transmission method may be the locomotive, but it is not the whole railroad . . . [continues]
X. No Phone Service Still for Silverton, Washington
A recent New York Times article reminds us that in America some communities still don't have telephone service, and won't have, until some basic economic principles change or some corporations have a change of heart.
Less than 65 miles from Seattle, the high tech capitol of the Northwest, tiny Silverton, Washington, sits in the shadow of high mountains and low ambition. No phone service or 911, just a police radio to call for help. That is, when the people who have the police radio are home to work it. Too expensive for a teleco to run a cable. Too costly for a wireless link.
How many other communities in America are like this? Many people throughout the west are off the electrical grid and the PSTN deliberately, since they build houses where no utility lines exist. But that's a different thing than a town, no matter how small, having never had phone service at all.
http://www.TelecomWriting.com/Telecomnews/Silverton.htm
XI. Two Nice Sites to Visit
Featuring many nice telephone sounds in RealAudio, Diamond Dave's Telephone World includes many telecom resources.
http://members.xoom.com/phworld/index.html Dead link
A nice hacker site
"John Smith", a long time hacker, presents a hacker related site filled with telephone related images, useful text files, and good links. A really good scanning file covering toll free numbers. Don't know what scanning is? Go over and take a look. But if you find an interesting number, please e-mail him to keep that file current. Check it out at:
http://www.internettrash.com/users/bft/ Now under construction
XII. The I Told You So Department
"But hackers agree on one thing: There's a witch hunt on to persecute people like Mitnick who explore computer and phone networks for the challenge and thrill.
'They're going to crucify him," says Tom Farley, an intense man in a Patagonia jacket and jeans who drove up from Carmichael. He publishes a journal on the minutia of telephone systems. "If they had a cross they would nail him to it."
San Francisco Chronicle, April 2, 1995
I was wrong in a way. Instead of a quick death they have let him bleed slowly for year after year. Entrapped by a cabal, persecuted by the zealous, and feared by the dim-witted, Mitnick has spent more time in jail than most rapists and child abusers. He is the first political prisoner of the information age.
Support Kevin:
http://www.kevinmitnick.com/ Dead site
See you in a couple of weeks, Tom Farley