TELECOM Digest Wed, 5 Jan 94 16:39:00 CST Volume 14 : Issue 9 Inside This Issue: Editor: Patrick A. Townson Re: US Digital Cellular Standard (ebcguss@ebc.ericsson.se) Re: US Digital Cellular Standard (Dan J. Declerck) Re: Digital Cordless Phones Question (KATHY1310@delphi.com) Re: Digital Cordless Phones/Rolm Switch (Kathleen Denial) Re: "Anonymous Call Rejection" - Could be Dangerous (Oliver Rothe) Re: "Anonymous Call Rejection" - Could be Dangerous (Curtis R. Nelson) Re: "Anonymous Call Rejection" - Could be Dangerous (Jon Edelson) Re: "Anonymous Call Rejection" - Could be Dangerous (John R. Levine) Re: "Anonymous Call Rejection" - Could be Dangerous (Mark Blumhardt) Re: Connecting Two Phone Lines to One Phone Jack (Keith McNeill) Re: V.35 to RS-232 Conversions (David Weiss) Re: Telix and Busy Signals (Steven J. Tucker) Re: ITU Method For Writing Telephone Numbers (Fernando Lagrana) Re: ITU Method For Writing Telephone Numbers (Carl Moore) Re: ITU Method For Writing Telephone Numbers (Ketil Albertsen) 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 GEnie. 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 compilation-copyrighted by Patrick Townson Associates of Skokie, Illinois USA. We provide telecom consultation services and long distance resale services including calling cards and 800 numbers. To reach us: Post Office Box 1570, Chicago, IL 60690 or by phone at 708-329-0571 and fax at 708-329-0572. Email: ptownson@townson.com. ** 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. For a copy of a helpful file explaining how to use the information service, just ask. TELECOM Digest is gatewayed to Usenet where it appears as the moderated newsgroup comp.dcom.telecom. It has no connection with the unmoderated Usenet newsgroup comp.dcom.telecom.tech whose mailing list "Telecom-Tech Digest" shares archives resources at lcs.mit.edu for the convenience of users. Please *DO NOT* cross post articles between the groups. All opinions expressed herein are deemed to be those of the author. Any organizations listed are for identification purposes only and messages should not be considered any official expression by the organization. ---------------------------------------------------------------------- From: ebcguss@ebc.ericsson.se Subject: Re: US Digital Cellular Standard Reply-To: ebcguss@ebc.ericsson.se Organization: Ericsson Date: Wed, 5 Jan 1994 10:45:33 GMT In article 2@eecs.nwu.edu, weiyun@extro.ucc.su.OZ.AU (Weiyun Yu) writes: > It has come to my attention that the digital cellular standards > adopted by US carriers are not going to be compatible with what we > have adopted in Australia, GSM. I am interested in finding out a bit > more about the US systems but cant find any FAQ on the subject. > My specific questions are: > 1. What are the pro and cons of the US standards vs GSM. There are basically three standards -- AMPS used in North America, JSM (?) used in Japan, and GSM used in the rest of the world. It's the same with TV-sets. In Europe we have PAL and SECAM, in the U.S. they have NTSC; don't know about the rest of the world. As I see it, this is a producer-pushed scenario that we will have to live with. The reason is that the producers will be able to sell more terminal-units -- those who need to be accessable in all three areas will have to buy three units instead of one. I don't know a whole lot about the technical differences on the different standards. > 2. Is there going to be some degree of compability encorporated into > the 2 standards so that international roaming could be achieved. With GSM, all the operators must be open for roaming with other operators. But for roaming between GSM, AMPS, and JSM, I think we'll have to wait. > 3. What is the future of digital cellular? Is there going to be a third > standard that can be used world wide? There are at least two companies working on a satellite based system for digital mobile communication that is to be working worldwide. As I understand these will be working as plain cellular phones when inside i.e. a GSM- cell, but as a satellite-phone when you are in the desert or someplace else without access to a cellular provider. Claes ------------------------------ From: declrckd@rtsg.mot.com (Dan J. Declerck) Subject: Re: US Digital Cellular Standard Date: 5 Jan 1994 19:21:38 GMT Organization: Motorola Inc., Cellular Infrastructure Group In article , Weiyun Yu wrote: > 1. What are the pro and cons of the US standards vs GSM. N-AMPS, ADC, and DS-CDMA all offer, at least, 2x the capacity of GSM. NAMPS and CDMA do not have the pulsed-noise interference of GSM. CDMA has the potential to have a longer talk-time. GSM has terrible data services vis-a-vis' Group 3 Fax. > 2. Is there going to be some degree of compability encorporated into > the 2 standards so that international roaming could be achieved. > 3. What is the future of digital cellular? Is there going to be a third > standard that can be used world wide? The frequencies and access methods (GSM is TDMA/GMSK each channel is 200 KHz, ADC is TDMA/QPSK channels ea 30 KHz, CDMA is DS-CDMA ea channel 1.25 MHz) are completely incompatible. GSM is like ISDN over the air, whereas the other standards aren't so rich. Dan DeClerck EMAIL: declrckd@rtsg.mot.com Motorola Cellular APD Phone: (708) 632-4596 ------------------------------ From: KATHY1310@delphi.com Subject: Re: Digital Cordless Phones Question Date: Wed, 5 Jan 94 16:46:06 EST Organization: Delphi Internet I have an AT&T Model 9100. As you have stated, I have had no problems with range within my house (or for that matter in my next door neighbor's house. However, the range outside my house is only about 3/8 mile (it's very hilly and densly populated). I have not exper- ienced any quality problems as of yet. ------------------------------ From: kathi_denial@net.com (Kathleen Denial) Subject: Digital Cordless Phones/Rolm Switch Date: 5 Jan 94 17:12:29 GMT Organization: N.E.T. I am currently looking into using digital cordless phones in conjunction with our Rolm 9751 switch. Has anyone tried this yet? My idea is to assign a persons second line to a SLI channel. The purpose is to allow people reach the IT department when we are away from our desks. As most of you know many problems can be solved immediately if the user can reach you, and get an answer. Has anyone tried this application/do you have any suggestions? Also does anyone have any information on the technology used for the digital cordless phone. Thanks, Kathi Denial ------------------------------ From: Oliver Rothe Subject: Re: "Anonymous Call Rejection" - Could be Dangerous Organization: ISGI GmbH Date: Wed, 5 Jan 1994 09:31:12 GMT Jack Decker (ao944@yfn.ysu.edu) wrote: > If you think that the fire example is farfetched, just consider that > there are other situations where you might want folks to reach you ... For example, people from other countries (Here in Germany there is still no caller ID, although I assume that the switching systems used would allow for it in most parts of country). Oliver Rothe isgi@ztivax.zfe.siemens.com also reachable via: 100265.1543@compuserve.com [TELECOM Digest Editor's Note: However people in other countries, like people in a central office just a couple miles from me not yet equipped with Caller-ID can get through; the difference is the display box says 'out of area' rather than 'private'. That is the key. Even people who refuse to take calls from blocked numbers still accept calls from those sources where the calling number is not known (by the exchange). PAT] ------------------------------ Date: Wed, 5 Jan 1994 12:50:19 CST From: CRN@VAX3.ltec.com Subject: Re: "Anonymous Call Rejection" - Could be Dangerous In TELECOM Digest V14 #6 (Thu, 5 Jan 94), Jack Decker wrote regarding Caller ID Blocking and Anonymous Caller Rejection: > ... and when Caller ID is offered here, it will be a trivial matter > for me to program the dialer wo prepend 1167 to all outgoing calls ... and, > ...By the way, I always get a chuckle out of the folks who say "if you > don't want me to know your number, don't call me!" Believe me, if I > knew that someone I was contemplating calling felt that way, there's > no way I would call them, just because they sound like the sort of > paranoid personality I wouldn't want to deal with. ... Now who's the paranoid one? Another thought: If someone knocks on your door, do they have the right to cover your peep hole ("Visitor ID Blocking"). Curtis R. Nelson, P.E. email: cnelson@ltec.com Lincoln Telephone Company phone: (402) 476-4886 1440 'M' Street fax: (402) 476-5527 Lincoln, NE 68508 ------------------------------ From: winnie@flagstaff.princeton.edu (Jon Edelson) Subject: Re: "Anonymous Call Rejection" - Could be Dangerous Organization: Princeton University Date: Wed, 5 Jan 1994 18:44:59 GMT The question that one must ask oneself when using something like 'Anonymous Call Rejection' can be phrased 'How open do I want to leave my door?' This is not a trivial question; my response is always to put the tools out there so that individuals can make the choices for themselves, as I figure that the question is difficult enough that I shouldn't be answering it for someone else. To take the fire example of this thread: [The situation was a neighbor noticing a house fire, and attempting to call, but getting rejected because of anonymous call rejection.] If the neighbor's front door was unlocked, then people could run in and wake everyone up, or put out the fire. But leaving the door unlocked is a risk. Do people have little glass boxes with 'Pull for emergency access' on their doors, so that anyone can get in if necessary? No, because that would defeat the purpose of the lock on the door. But people do give keys to neighbors, because the additional risk is offset by the enhanced safety of having another set of (trusted) eyes able to look out for you. I tend to turn off the ringer of my phone when I want to sleep. That way people can call me at any time without worrying about disturbing me. However, if there was an emergency when I was in bed, my phone would be worse than useless. I doubt that I would ever get anonymous call rejection; my only need to know who is calling is for convenience. But I say 'Let it be an option, allow people to choose the risk.' Jon ------------------------------ Date: Wed, 5 Jan 94 14:46 EST From: johnl@iecc.com (John R Levine) Subject: Re: "Anonymous Call Rejection" - Could be Dangerous Organization: I.E.C.C., Cambridge, Mass. Does anyone actually have Anonymous Call Rejection in service now? Is it useful? It impresses me as one of those features which you get for about a week, then get rid of because it's utterly worthless. Perhaps I'm suffering from a failure of imagination, but I find it difficult to understand the mindset of people who are too scared to answer the phone if they don't know in advance who the call is from. People who are concerned about annoyance callers should consider Call Block, which lets you enter a list of numbers from which you won't receive calls. You can either enter explicit numbers, or tell it to add whoever just called, even if the call had CLID blocked. It's available the same places as other CLASS services, including some where CLID isn't, because it doesn't present the privacy problems. Regards, John Levine, johnl@iecc.com, jlevine@delphi.com, 1037498@mcimail.com ------------------------------ From: msb@advtech.uswest.com (Mark Blumhardt) Subject: Re: "Anonymous Call Rejection" - Could be Dangerous Organization: U S WEST Advanced Technologies Date: Wed, 5 Jan 1994 20:45:49 GMT I have not seen the tariff for this service, but I think that a lot of readers on this thread are missing an important distiction. This distinction is between a number not being available and being blocked. That is, the calling party number may not be available for inter-LATA calls, and in my opinion, these calls should not be rejected. This is quite different than if the delivery of a number has been blocked (i.e. *67), which is when calls should be rejected by this service. If the service is worth anything, it would make this distiction. ISUP carries the calling party number and address presentation restriction information (see TR-246 T1.113.3 3.7). Hence, the service could reject calls where calling party number delivery has been blocked and allow calls when the number is not available. Just my observation, Mark ------------------------------ Date: Wed, 5 Jan 94 10:03:42 EST From: mcneill@ngt.sungard.com (Keith McNeill) Subject: Re: Connecting Two Phone Lines to One Phone Jack > [TELECOM Digest Editor's Note: Well, I guess we know a few things > If you have two lines from telco, then what you do is at the modular > connection box depends on the kind of phone(s) you are using. If you > have a true two-line phone, then connect the four wires to the four > screw terminals as indicated by the color markings for each. In > addition you attach the four wires from the cover of the modular box > to the associated screw terminals in the same way. Plug in your two > line phone and it should work okay. If you are using two separate > phones, we do it a bit differently. Inside the modular box, have the > four wires connected as above, but from the Y/B terminals, run two > little jumper wires to a second modular box you bought from Radio > Shack or similar. Connect the jumper wires from the Y/B screws of > the first box to the R/G screws in the new, second modular box. Now > plug your second phone into your second box. Actually, Radio Shack sells an RJ11 adaptor that splits out the 1st and second line for you. It looks like a normal one phone jack to two phone jack adaptor, except it has three jacks. One for line one, one for line two and one for both lines. There is no need to do the extra wiring. On a side note, I recently called NY Telephone (or NYNEX as they want to be called now) about getting a second phone line installed in my apartment. I was shocked to get a quote of $185 for the second line (first line costs about $60). This is the price for installing a totally different phone line in the apartment. I complained a little that they didn't need to do that as there was a perfectly good second pair coming into the apartment I didn't get very far as the customer service rep wasn't technical. Is there really any need to get a totally seperate line into my apartment? Diamond State Telephone (Delaware) was able to put a second line on the second pair. Is NYNEX just trying to gouge me? Keith D. McNeill SunGard Capital Markets +1 212 371 1116 560 Lexington Ave, 10th Floor mcneill@ngt.sungard.com New York, NY, 10022 USA [TELECOM Digest Editor's Note: Not necessarily. Telco outside plant records are in notoriously bad condition in some places. The rep may have actually not had any record of the second pair in your apartment or may have had a record of it but shown it to be actually a multiple of someone else's first pair or what-have-you. Have you tested that pair to see if it is alive (with someone else's service because some installer in the past never opened it up at the pole) or if it is in good condition? Have you traced it back to the demarc, such as in the basement of the building where you live? If you can get that second pair back as far as the demarc for the building (or yourself, whichever applies), then you have a second pair and it should not be required for telco to make any visit to your home with the high cost for same. You have to be careful though; make sure that set of wires you are looking at actually goes somewhere and reaches the demarc. If not, then you are possibly stuck for the high installation costs of a second line. You should trace that pair first, getting it back to the demarc if at all possible. Note on the demarc there may be some notations (little tags tied on with bits of string are common) telling the installers what goes where. If you see a notation saying something like 'cable 74, pair 29' or similar then when you call back to the business office if you get the same rap about how a new line has to be installed in your apartment tell the rep you *think* 'cable 74 pair 29' is there already. Note I emphasize 'think'. You're not a phone installer so don't try to act like one. But stress you have seen complete wires back to the demarc which appear to be idle, and you are wondering if the rep will please have someone confirm or correct the outside plant records. PAT] ------------------------------ From: D_WEISS@delphi.com Subject: Re: V.35 to RS-232 Conversions Date: Wed, 5 Jan 94 21:31:17 EST Organization: Delphi Internet V.35 to RS-232 Converters are readily available and come in several types, from simple in-line, line powered converters (as for example thoes manufactured by RAD) to A/C powered devices with full line driver capability (Dataprobe). For Information on V.35 specifications, get a copy of the CCITT V series specs. Hope this helps, David Weiss ------------------------------ From: dh395@cleveland.Freenet.Edu (Steven J Tucker) Subject: Re: Telix and Busy signals Date: 5 Jan 1994 06:24:42 GMT Organization: Case Western Reserve University, Cleveland, OH (USA) Reply-To: dh395@cleveland.Freenet.Edu (Steven J Tucker) In a previous article, ericw@seanews.akita.com (Eric Walrod) says: > Okay, I just set up a new PC Logic 14.4kbps Internal Fax/Modem for a > friend, and set-up deltaComm's Telix v3.21 for it. > I CANNOT get Telix to recognize a busy signal. I am already using > ATX4V1 to no avail (sp?). Is your modem actually reporting 'BUSY' when you get a busy signal? If it is, the problem is prob in the configuration of Telix. Type ALT-O and choose option M (Modem and Dialing), Suboption G of this menu defines the 'No Connect Strings'. Make sure 'BUSY' is listed there. Steve ------------------------------ Date: Wed, 5 Jan 1994 14:31:49 +0100 From: LAGRANA Subject: Re: ITU Method For Writing Telephone Numbers In Telecom Digest V13 #842, Anthony D. Vullo asks: > What is the ITU reference for the standard method of writing > telephone numbers? I've noticed the following: > (plus symbol) (country code) (city/area code) (number) Toby Nixon is right when answering that ITU's corresponding reference is Recommendation E.123. This Recommendation was adopted in Melbourne in 1988 and is still in force. Its title is "Notation for national and international telephone numbers". Let me thank Toby Nixon for his answer. Let me not thank George Zmijewski for his, hhhuuummm, rather rough one (I'm both French and TSB official, ha, ha, ha!!!). Fernando Lagrana International Telecommunication Union Telecommunication Standardization Bureau Editor, Catalogue of Recommmendations Coordinator, Electronic Document Handling Internet: lagrana@itu.ch Voice: + 41 22 730 58 94 Fax: + 41 22 730 58 53 X.400: SURNAME=lagrana, PRIVATE_DOMAIN=itu, ADMIN_DOMAIN=arcom, COUNTRY=ch ------------------------------ Date: Wed, 5 Jan 94 9:28:52 EST From: Carl Moore Subject: Re: ITU Method For Writing Telephone Numbers This responds to mzmijews@mgzcs.demon.co.uk (George Zmijewski): You write: > MYCOMPANY NAME (0123) 123456 > international +44 123 123456 > This seems a bit stupid -- the American system (if there is any), > seems to be much better -- just the area code plus number. Everybody > knows when to add 1 or when to add 001 (if calling from another > country). If an American (i.e. country code 1) telephone number (including the area code) is being to someone outside, it needs +1 in front. By coincidence, a leading 1 is used for long distance within country code 1. ------------------------------ From: ketil@edb.tih.no (Ketil Albertsen,TIH) Subject: Re: ITU Method For Writing Telephone Numbers Organization: T I H / T I S I P Date: Wed, 5 Jan 1994 16:48:00 GMT In article , mzmijews@mgzcs.demon.co.uk (George Zmijewski) writes: > This seems a bit stupid -- the American system (if there is any), > seems to be much better -- just the area code plus number. Everybody > knows when to add 1 or when to add 001 (if calling from another > country). Remembering that USA is 1 is fairly simple, but remembering that Norway is 47 is more difficult. Adopting the American practice of not including country code at all is simply not applicable outside North America. > In Europe 0 is being now used as prefix for area code > numbers and 00 as prefix for country codes. Not at all true, as a general rule. Here in Norway, we currently use 095 1 xxx... to dial North American numbers. Up until last year, a (single) leading 0 generally indicated "not a local, ordinary phone no" but anything else, like long distance (0 + area code), out-of-country (0 95 + country code + national no), directory service (0 180 Nordic countries, 0 181 International), weather forecast, news summary, error reports for the phone system etc.etc.etc. But during 1993, area codes have been removed; you can now in principle move all across the country keeping your old number ("for administrative reasons" they will currently give you a new number, but they admit that one of the reasons for dropping area codes was to open up this possibility from a technical point of view), and the leading zero has been removed from all special services. (There were three special emergency numbers which did have double leading zeros, for Fire alarm, Ambulance and Police respectively; they now have a single leading zero). So it all boils down to 0 being a perfectly ordinary digit, even as a leading one, in the Norwegian national numbering plan. > But then some French idiots come up with a stupid numbering system > (for Paris *and* Greater Paris +331 xxxxxxxx rest of the country +33 > xxxxxxxx ). According to my phone book, France is 33. Then, if the first digit is 1, then it is Paris, if the first digit is something else, it is NOT Paris but some other area. Is that really "stupid"? You could similarly classify it as stupid that any international number starting with +4722 is Oslo, starting with +4772 or +4773 is Trondheim, and the est of the country is +47 and not +4722, +4772 or +4773. But we see it differently -- the first digits after the country code indicate which city. Plain and simple: There are always eight digits, the leading ones hinting about the location. (Until they open up for taking your phone number along when you move to another city.) ------------------------------ End of TELECOM Digest V14 #9 ****************************