TELECOM Digest Wed, 5 Oct 94 11:32:00 CDT Volume 14 : Issue 388 Inside This Issue: Editor: Patrick A. Townson Communications In/After a Disaster (Kevin Jessup) Free E-Mag Covers Wireless, ATM, Frame Relay, SMDS, FDDI (David S. Lewis) Correction: 310 Overlay Details (Greg Monti) networkMCI Wants to do Local Dial Tone (Greg Monti) Re: Card Call Ripoffs; Calling China Cheap (Laurence Chiu) TAPISDK/ATVSP.TSP Problem (Douglas H. Quebbeman) Re: Recommendations For Answering Machines? (Al Varney) Re: Okay, So I Want to Start My Own Local Telco ... How? (Al Varney) Re: NYNEX to Stop Charging For Touch-Tone! (Wes Leatherock) Re: Fax DID Technologies - What is E&M (Garry Gruenke) Re: True Voice ... True Difference? (Henry Wertz) Re: True Voice ... True Difference? (Ken Krechmer) Re: British Telecom Caller-ID (Ed Ellers) Re: Questions on Using GPS Time Codes For Network Timing (Ed Ellers) TELECOM Digest is an electronic journal devoted mostly but not exclusively to telecommunications topics. It is circulated anywhere there is email, in addition to various telecom forums on a variety of public service systems and networks including Compuserve and America On Line. It is also gatewayed to Usenet where it appears as the moderated newsgroup 'comp.dcom.telecom'. Subscriptions are available at no charge to qualified organizations and individual readers. Write and tell us how you qualify: * telecom-request@eecs.nwu.edu * The Digest is edited, published and compilation-copyrighted by Patrick Townson of Skokie, Illinois USA. You can reach us by postal mail, fax or phone at: 9457-D Niles Center Road Skokie, IL USA 60076 Phone: 708-329-0571 Fax: 708-329-0572 ** Article submission address only: telecom@eecs.nwu.edu ** Our archives are located at lcs.mit.edu and are available by using anonymous ftp. The archives can also be accessed using our email information service. 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Any organizations listed are for identification purposes only and messages should not be considered any official expression by the organization. ---------------------------------------------------------------------- From: kevin.jessup@mail.mei.com (Kevin Jessup) Subject: Communications In/After a Disaster Date: Wed, 5 Oct 1994 11:24:13 GMT Organization: marquette electronics, inc I'm interested in your experiences and opinions regarding emergency telecommunications employed in the event of a disaster. Disasters such as earthquakes, hurricanes, floods, tornados, even riots. I'd like any info/opinions you have regarding the survivability of the commercial telecommunications infrastructure after such events and any experience you have on how fast service was restored after the event. I'm aware of the importance of amateur radio when all access to commercial telecomm fails. I won't discount the occaissional ;-) usefullness of Citizens Band either. What I am looking for is your experiences using cell phones or even internet services such as Internet Relay Chat after a disaster hits. I have both cellular phones and VHF/UHF amateur radio for my use. Having lived in Wisconsin all my life, I have only experienced a "small" tornado. I'm looking for opinions from those who have had to deal with a more wide-spread event. How robust is the cell phone infrastructure? In a very localized disaster (tornado) you can still probably hit more than one cell site (with your cell phone) even if one or two towers (receive sites) are wiped out. Also, assume here that local land-line communication is dead or overloaded. In that case, does having a cell phone make any difference (the cell sites eventually access the land-lines anyway)? I also understand that cell phones are auto- matically given alternating priority (via the Access Overload Class value burned into every cell phone) in the event of system overload. Did you experience this priority switching? Were you able to access during certain hours but but others? How important and responsive were local government emergency services to your IMMEDIATE emergency COMMUNICATIONS needs? If you utilized an amateur radio operator's help (perhaps via an Amateur Radio Emergency Services station), do you feel it served your purpose (provided help or relayed the message) in a timely fashion? Had you NOT used it or used an alternative method, would/did help have arrived (or would the message have been delivered) any faster (or at all)? What about evolving commercial telecomm? Cell sites will shrink in size and power requirements as technology advances. The Steinbrecher mini-cell fits in a large trunk and costs 1/10th a conventional sell site. This make battery/generator back-up more feasible. Will commercial telecomm do that? The mini-cell also encourages more densely packed cells resulting in better coverage and redundancy. Looking into the future, are there any opinions on the ambitious (some much more so than others) LEOS (Low Earth Orbitting Satellite) projects and their promise of hand-held coverage immune to local disasters? How dependent will the various LEOS be on ground stations? How many ground stations are actually required? Finally, amateur radio usually (only?) provides text (files and keyboard-to- keyboard) and voice (even if via Morse code) communication. If multimedia services were available via amateur radio (high-speed file transfer, fax) would you have used them? Note that "business related" traffic is NOT legal via amateur radio. Only personal ("Hi honey. We're just fine.") and emergency ("She's trapped and has a broken leg!" or "The dam is about to burst!") traffic is allowed. I've found no shortage of articles on the importance of amateur radio in an emergency situation in the amateur radio related publications (QST, 73, Amateur Radio, etc). I agree with them. However they are seldom self- critical. On the other hand, consumer publications such as Mobile Office now regularly carry stories on how cell-phones and cell-phone-based fax and data modems did the job after disasters. Just how much of this is hype and how much is true? All serious commentary is welcome. I also would enjoy reading your speculations on the future. Thanks. This really isn't a survey. Just looking for opinions and hoping to stimulate a little discussion. :-) No flame-wars please. kevin.jessup@mail.mei.com Marquette Electronics, Inc. Milwaukee, Wisconsin, USA N9SQB, ARRL, Amateur Radio ------------------------------ From: callewis@netcom.com (David Scott Lewis) Subject: Free E-Mag Covers Wireless, ATM, Frame Relay, SMDS, FDDI Organization: NETCOM On-line Communication Services (408 261-4700 guest) Date: Wed, 5 Oct 1994 11:39:10 GMT The long-awaited (and long overdue) second part of Issue 940425 will be transmitted over the next several days. As a reminder, the HOTT (Hot Off The Tree) Internet-based e-magazine is a FREE, monthly (10/year) update on the latest in VR, telepresence & intelligent user interfaces; AI & "intelligent" agent-oriented software; interactive multimedia & game development; wireless communications & PCS; mobile, portable & handheld computing devices; neural, fuzzy & genetic systems; nanotechnology, bio/microsensors & molecular electronics; voice I/O & handwriting recognition; HDTV & I-TV; ATM, frame relay & FDDI; visual programming, object-oriented databases & client/server application development; fractals, wavelets & quadtree data structures for image & signal processing; ULSI circuits & megacells; optical computing & erasable optical disks; PC telephony & PC TV; animats & micro/telerobotics; and, other bleeding-edge technologies. For a FREE subscription, send a request TODAY to listserv@ucsd.edu . The "Subject" line is ignored; leave it blank or type in whatever you'd like. In the body of the message, input: SUBSCRIBE HOTT-LIST . Do NOT include first or last names following "SUBSCRIBE HOTT-LIST"; this is a quirk of the UCSD listserv software. You will receive subscription confirmation from the UCSD host site. Disclaimer: Please note that although the mailing list is currently maintained at UCSD, there are no official ties between HOTT and the University of California. TABLE OF CONTENTS ================= ********************************************************************** *** * SPECIAL: A FULL-TEXT TUTORIAL ON GENETIC & EVOLUTIONARY PROGRAMMING * * (see item [Z], the last article in Part 2) * ********************************************************************** *** VIRTUAL REALITY IEEE Computer Graphics and Applications: Special Issue on VR ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ [1] Virtual reality (introduction to the special issue) [2] What are virtual environments? [3] Human factors in the design of an immersive display [4] Teaching your system to share (PC-based VR) [5] Resource file: Other contacts from the CG&A special issue [6] Visualization and analysis using virtual reality [7] Virtual reality as it really is [8] Inching closer to reality (emerging markets profile) [9] Engineers develop real-world apps for VR (medical applications) MOBILE & WIRELESS COMPUTING ********************************************************************** *** * SPECIAL: TEXT OF SPEECH PRESENTED AT MOBILE '94 BY THE PRESIDENT & CEO * * OF PHILIPS SEMICONDUCTORS * * (see item [X], the second to last article in Part 2) * ********************************************************************** *** [10] No computer is an island (data transfer for road warriors) [11] A special report from The (London) Financial Times on PDAs [12] The wireless office [13] The cost of wireless data [14] Computing out of bounds (tools for the fully-armed road warrior) [15] Better batteries INTERACTIVE TV [16] The interactive TV crusade [17] Real-time OS, services drive TV decoders NEURAL NETWORKS & SEVENTH GENERATION COMPUTING ^^^^^^^ [18] IBM writes plan for neural networks (handwriting recognition app) [19] Neural networks tackle manufacturing [20] Heaven in a chip (computing, circa 2020) INFOBAHN (hmmm, in Part 1 this section was titled "Information Superhighway") [21] Curtain's rising on a third generation of on-line services [22] A protest song -- '90s style (music on the 'Net) SPEECH RECOGNITION [23] Conversations with my PC [24] Say the word! (home automation apps) NANOTECHNOLOGY & MICROELECTROMECHANCIAL SYSTEMS (MEMS) IEEE Engrng in Medicine & Biology: Special Issue on Molecular Electronics ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ^^^ [25] Molecular electronics: Science and technology for the future [26] Resource file: Other contacts from the EMB special issue [27] Mirror, mirror (microscopic mirrors & MEMS for HDTV) COMPANY PROFILE [28] A juicy new Apple? SPECIAL FULL-TEXT REPORTS [X] Text of speech presented at Mobile '94 by the President & CEO of Philips Semiconductors [Z] Tutorial on genetic & evolutionary programming David Scott Lewis Editor-in-Chief and Book & Video Review Editor IEEE Engineering Management Review (the world's largest circulation "high tech" management journal) Internet address: d.s.lewis@ieee.org Tel: +1 714 662 7037 USPS mailing address: POB 18438 / IRVINE CA 92713-8438 USA ------------------------------ Date: Wed, 5 Oct 1994 10:35:08 EDT From: Greg Monti Subject: Correction: 310 Overlay Details After a piece I wrote appeared in the Digest saying that the 562 area code overlay would be restricted to existing California area 310 appeared, I received a very helpful message and fax from Marc O'Krent or of Marina Del Rey, CA. A 13-page fax from Pacific Bell to Marc tells a complicated tale. The new 562 code was once intended to be for wireless services only, which would migrate from the existing 310, 213 and 818 area codes. The change now is that 562 will also be used to relieve number exhaustion for landline phones in the 310 area and may be used to relieve landline NXX exhaustion elsewhere. The 310 landline overflow to 562 is *in addition to*, not instead of, wireless users from 213 and 818. Any kind of user from 213 and 818, not just wireless ones, may also end up in 562 someday. Phase I of the change, beginning 2 Sept 1995, has 562 being used to implement new NXX codes of tandem users that would otherwise have been in 310. I assume a "tandem" user is one who connects to the landline telephone network via trunk-side, rather than line-side interconnection. I suspect that cellular, beeper, PCS and large corporations are typical tandem users. In Phase I, no existing numbers would be changed. Phase II will include all services from both tandem and end-office switches in the 310 land area. During phase II, there may be a third step: enlarging the overlay to include "all services" in the 818 and 213 areas. Thus 562 could be used to relieve up to three other area codes, which should hold the LA basin until 2000. A note in the Pacific Bell copy also notes that 619 will likely split within five years. Greg Monti, Tech Mgr, FISPO, Distribution Division National Public Radio Phone: +1 202 414-3343 635 Massachusetts Av NW Fax: +1 202 414-3036 Washington, DC 20001-3753 Internet: gmonti@npr.org ------------------------------ Date: Tue, 4 Oct 1994 18:32:33 EDT From: Greg Monti Subject: networkMCI Wants to do Local Dial Tone According to a story on page C1 of the October 4, 1994, {Washington Post}, and in other media, MCI's local service division, networkMCI, has applied for franchises to provide local dial tone service in Maryland, Pennsylvania, Washington state, Michigan and Illinois. networkMCI intends to serve mainly businesses, although they applied for the residential market in Michigan as well. MCI would provide dial tone, directory assistance, call waiting, call forwarding and 911 emergency, among others. MCI already has such authority in two states, New York and Massachusetts. An MCI spokesman said that the company is applying for regulatory authority state by state since the telecom bill did not pass in Congress this year. MCI has requested that all involved states require the Bell Operating Companies serving them to provide number portability so customrs can change local phone companies and keep their numbers. The article notes that the biggest issue still unresolved is how much MCI and the other local company will charge each other to transport (local) calls between companies. Greg Monti, Tech Mgr, FISPO, Distribution Division National Public Radio Phone: +1 202 414-3343 635 Massachusetts Av NW Fax: +1 202 414-3036 Washington, DC 20001-3753 Internet: gmonti@npr.org ------------------------------ From: lchiu@crl.com (Laurence Chiu) Subject: Re: Card Call Ripoffs; Calling China Cheap Date: 4 Oct 1994 19:20:53 -0700 Organization: CRL Dialup Internet Access (415) 705-6060 [login: guest] In article , Wm. Randolph Franklin wrote: > What is the best way to call China, particularly using a calling card? > I've spent well over an hour talking to ATT, MCI, and Sprint. Their > rates are so close to each other, yet so byzantine, that they appear > [TELECOM Digest Editor's Note: There is no such thing as a cheap call > to China. The rates are quite high, anytime day or night where calling > cards are concerned, as well as with call-back schemes. I don't know > why this is, other than perhaps the telecom administration in China and > the carriers here have some difficulty in reaching mutually acceptable I guess it depends upon what you mean cheap. At the moment via MCI and using their International Friends and Family scheme I get a rate of $0.73/minute during week days and $0.49/min during weekends. This is to one number only but I could designate two others. One is enough for me at the moment. This rate is good until Nov 6 when it changes to $0.98 8pm-2pm and weekends and $1.35 otherwise to that number. At that time I will switch back to AT&T who had pretty decent rates also. Of course using a calling card might raise those rates somewhat. Laurence Chiu lchiu@crl.com Walnut Creek, California Tel (work) (510)412-4730 From: dougq@iglou.iglou.com (Douglas H. Quebbeman) Subject: TAPISDK/ATVSP.TSP Problem Organization: IgLou Internet Services Date: Wed, 5 Oct 1994 15:58:15 GMT I have problems getting the MCI Voice driver going, as well as the ATVSP.TSP driver. Comparing the source code of the version resource for the TAPI Dialer driver (VERSION.RC) with the source for the version resource for the Voice driver (SHIPVER.RC) shows some differences that may be implicated. The version resource must be in an acceptable format for the control panel thingie to load it. Anybody licked this problem yet? Douglas H. Quebbeman (dougq@iglou.com) ------------------------------ From: varney@usgp4.ih.att.com (Al Varney) Subject: Re: Recommendations For Answering Machines? Organization: AT&T Network Systems Date: Tue, 4 Oct 1994 04:36:02 GMT In article , Michael Rosen wrote: > I'm considering buying an answering machine as opposed to paying a > monthly fee to Bell Atlantic for their Answer Call voice mail system. > I was looking at AT&T's digital answering machines today. The only > thing they don't have that I kind of like is the ability to skip the > OGM. I like that someone's machine has that when I'm calling so I can > hit * and abort the message if I don't feel like waiting. I'd like to > extend that courtesy to people calling me (that is if they know it > exists which not all do). But the AT&T digital machines DO HAVE the ability to skip the OGM!!!! The documentation is crummy, but the machine is NICE. (I have the combined phone/answering machine called the "1545". The machine-only digital version should have the same features....) Anyway, on the pages where the "Examples of Mailbox Use" are described, you can do it TWO ways: 1) Have the caller press "1" during the OGM. It will abort the OGM and give the caller a BEEP. Record message normally. (I tested this ONE TIME, based on the use of 2, 3 and 4 for other mailboxes. Test it before you buy -- cause there's no reason to believe later versions won't change the un-documented behavior. And any such "1" should be more than just a brief tap of the button -- hold it down for a 1/2 second or so.) 2) Record an OGM for Mailbox 1, but none for boxes 2, 3 or 4. Tell your frequent callers to punch "2", "3" or "4" to interrupt your OGM -- normally this would switch them to the OGM for mailbox 2, 3 or 4, but since there isn't an OGM for those boxes, they just get a BEEP. And you get a display that shows the number of messages in EACH mailbox -- handy if you tell "4" to only one individual, for example. > I do want a machine that has a time stamp and remote access. The AT&T > model I was looking at has voice prompting for the remote access. > Is it worth the extra cost to go digital versus tape? IMHO, yes. Very clean sound, no wear. After 1 year, I've had to RESET the system once after my kids briefly interrupted power (no announcements or messages were lost due to power outage -- but it happened when they were playing with the machine and the "new messages waiting" indicator ended up stuck in an always-on state. Messages/announcements are safeguarded with battery-backup, but the state of the indicator must not be ...). Other than that, it works GREAT -- but I do need to get a longer handset cord. Al Varney ------------------------------ From: varney@usgp2.ih.att.com (Al Varney) Subject: Re: Okay, So I Want to Start My Own Local Telco ... How? Organization: AT&T Date: Tue, 4 Oct 1994 16:07:53 GMT In article , Paul Robinson wrote: > Peter Rukavina wants to know how to set > up a cooperative telephone company for a small group within a rural > area. > I can give him some ideas but if he's looking for something not very > expensive he's going to have a problem. > Average rule of thumb for a company deciding to put in its own PBX is > US $1000 per line plus about US $4 a month per line to cover damage to > equipment. IMHO, a PBX COULD BE a mistake, unless it is designed to support real outside plant analog/digital loops. One major difference between a typical PBX and a typical CO switch is in the expectation of high voltage/current spikes on lines. Even "campus-wide" PBX applications have to look at loop protection. But rural areas really need it. REA has lots of information regarding this area, and "lists" several CO switches it is willing to support with loan programs. You also need to think seriously about administrative/maintenance systems, which might cost more than the switch -- billing, tracking outside plant, repair orders, complaints, payroll, taxes, records, records, records ... Al Varney ------------------------------ From: Wes.Leatherock@f2001.n147.z1.fidonet.org (Wes Leatherock) Date: 03 Oct 94 10:08:01 -0500 Subject: Re: NYNEX to Stop Charging For Touch-Tone! Organization: FidoNet Nameserver/Gateway Quoting roy@mchip00.med.nyu.edu (Roy Smith): > There is an article in today's NYTimes saying that as one part of a > complex NYNEX-PSC agreement, starting January 1st, 1995, NYNEX will no > longer charge for touch-tone service. I can't believe it, after only > 27 years, they have finally come to the conclusion that touch-tone is > not a premium service anymore. Amazing. Rate design is a complex subject and Public Service Commissions, being at least partly political bodies, try to set rates in the way most palatable to customers, the great majority of whom are not big customers but modest residential users. > Am I the only person in the world who still doesn't have touch-tone, > because I don't want to pay the extra $0.50/month, or whatever it is? According to which figures you want to use, between 20 and 25 per cent of all telephones in the United States are still rotary dial. Wes Leatherock wes.leatherock@oubbs.telecom.uoknor.edu wes.leatherock@tranquil.torii.starship.com ------------------------------ From: garrenke@deepcove.com (Garry Gruenke) Subject: Re: Fax DID Technologies - What is E&M Date: 4 Oct 1994 15:12:16 -0600 Organization: DeepCove BBS McRae, Stuart writes: > I am researching technologies to allow DID use with the Fax Modems we > currently use for inbound fax routing. One solution I have founded > uses an interface called "E&M" which is available on some PABXs. It > appears to be some sort of variation of the DID protocol used for > telco lines. > Can someone explain what the E&M interface is, who defines it, where I > can get the definition, and how it works? > Also, our fax modems can support "DTMF" routing. Ascom in the UK > recently announced a FaxRouter which uses a basic rate ISDN connection > to the telco and an analog connection to two fax modems using DTMF. > This allows us to use our current fax modems for inbound routing (or > any other modems that support DTMF). > Are there any other products which will do this? Do any PABXs have the > capability to generate DTMF in this way? Are there any vendors offering > other DID solutions (anywhere worldwide, PABX based or stand alone) > which will connect to a fax modem supporting DTMF? The E&M interface uses some extra wires for signalling E (ear) M (mouth). There are several types of E&M interfaces, 2-wire and 4-wire refer to the number of wires needed for the voice portion, with a 2-wire interface you would have 2 wires for transmit and recieve and 2 or 4 more wires for the E&M leads. With the 4-wire interface you would have 2 wires for transmit and 2 wires for recieve and 2 or 4 more wires for E&M leads. Type I E&M uses 1 wire for an E-lead and 1 wire for an M-lead. Type II E&M uses 2 wires for E-leads and 2 wires for M-leads. An incoming seizure is signalled by a ground on the E-lead (Type I) or a short on the E-lead pair (Type II). An outbound seizure is signalled by battery on the M-lead (Type I) or a short on the M-lead pair ((Type II). There is more but this is the real meat of the interface. garry.gruenke@deepcove.com ------------------------------ From: Henry Wertz Subject: Re: True Voice ... True Difference? Date: 4 Oct 1994 18:06:56 GMT Organization: U of Iowa Panda System Reply-To: Henry@chop.isca.uiowa.edu In note , bd80519@bingsuns.cc.binghamton. edu (Paul R. Paradiso) writes: > Hello. Actually, at this point I would like to believe that there IS > a difference. The difference will probably be noticed in data > communications such as Modems, Fax, etc. It is amazing at how fast > the CPS rates can go up when the lines get clearer and clearer. I > have tested my modem on a line and when it picked up the line thru an > "ATA" command, all I heard was static, but was perfectly fine for > Voice. Since modems and fax, etc. send their tones at such a higher > speed today, they need as little blockage as possible. Hopefully this > will help, if not, I'm not surprised ... I doubt it ... the low frequencies have always been iffy, so most equipment leaves that 300hz down alone. I don't think it'll make a difference. In fact, it might cause a problem, since emphasizing one particularchunk of frequencies is not what a modem counts on 8-). ------------------------------ From: krechmer@ix.netcom.com (Ken Krechmer) Subject: Re: True Voice ... True Difference? Date: 4 Oct 1994 22:09:56 GMT Organization: Netcom In densaer@kaiwan.com (Rakesh Bharania) writes: > Several months ago, I called the True-Voice demo line when it first > went up (I forgot where I got the number from), and I couldn't tell > one whit of difference between the normal voice and the "enhanced" > one. Several days ago, I saw the Whitney Houston commercial and > decided to try again (hey, the line was new .. maybe it wasn't fully > working, right?) Again, I couldn't tell the difference. I even got > my dad to call this up, and HE couldn't tell the difference. > So is "True Voice" an actual technology or just a marketing move? The specification released by AT&T is Technical Reference 50150 Issue 2.0 March 1994. It shows the base boost around 300 Hz and also a full band gain boost of 4dB when level is below -17dBm0 for 1 second. If it sounds better or not I leave to others to decide. Ken Krechmer Technical Editor Communications Standards Review e-mail: kkrechmer@attmail.com ------------------------------ From: Ed Ellers Subject: Re: British Telecom Caller ID Date: Wed, 5 Oct 94 12:10:12 -0500 Organization: Delphi (info@delphi.com email, 800-695-4005 voice) Martin Cook writes: > When a line is about to receive a call the polarity of the line is > reversed prior to the ringing current being applied. If the customer > has Caller Display additional messages are interspersed between the > polarity reversal and the application of the ringing current. Now that's definitely different from North American practice -- here the CNID data burst is sent between the first and second rings. [TELECOM Digest Editor's Note: And typically, immediatly following the first ring, with some dead space following the end of the transmission and the start of the second ring. PAT] ------------------------------ From: Ed Ellers Subject: Re: Questions on Using GPS Time Codes For Network Timing Date: Wed, 5 Oct 94 12:16:32 -0500 Organization: Delphi (info@delphi.com email, 800-695-4005 voice) Mike Foltz writes: > What makes GPS so special for being a timing reference? Probably that it's the only time signal source at present that is available nationwide (and worldwide) over a line-of-sight signal path; other sources in various countries are either shortwave (like WWV, CHU or JJY), long wave (like WWVB or WWVL, or the BBC's Radio 4 UK) or even local medium wave AM stations (such as Cuba's Radio Reloj network), and none provides 100% reliable 24-hour nationwide coverage. ------------------------------ End of TELECOM Digest V14 #388 ****************************