TELECOM Digest Thu, 2 Mar 95 20:05:00 CST Volume 15 : Issue 130 Inside This Issue: Editor: Patrick A. Townson Re: Credit Checking on Cellular Customers (Doug Fields) Re: Yes, Yung'uns. CNID -is- Logged at Your Local CO (Linc Madison) Re: yes, Yung'uns. CNID -is- Logged at Your Local CO (Gary Novosielski) Re: What is ESF and D4? (Chip Sharp) Re: What is ESF and D4? (Mike Schomburg) Re: Anyone Heard of SMR - Specialized Mobile Radio? (David S. Taylor) Re: Anyone Heard of SMR - Specialized Mobile Radio? (Travis Russell) Re: Information Wanted on Hotel Telephone Billing (Travis Russell) Re: Does Bridge Affect Modem? (John Dearing) Re: Free Expression and the Information Highway (Kevin J. Shea) Re: 500 Place-A-Call Working (Stan Schwartz) Re: What is a Digital PBX? (Fred R. Goldstein) Re: What is a Digital PBX? (Travis Russell) Re: The Unintentional Date/Chat Line (Steven H. Lichter) Computer Modeling Software for AM Tower/Antenna Studies? (Zuhair Moin) Re: Saying Hello in Other Languages - Summary (Gene Retske) 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 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: 500-677-1616 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. For a copy of a helpful file explaining how to use the information service, just ask. ************************************************************************ * * TELECOM Digest is partially funded by a grant from the * * International Telecommunication Union (ITU) in Geneva, Switzerland * * under the aegis of its Telecom Information Exchange Services (TIES) * * project. Views expressed herein should not be construed as represent- * * ing views of the ITU. * ************************************************************************ * Additionally, the Digest is funded by gifts from generous readers such as yourself who provide funding in amounts deemed appropriate. Your help is important and appreciated. A suggested donation of twenty dollars per year per reader is considered appropriate. See our address above. 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: admiral@panix.com (Doug Fields) Subject: Re: Credit Checking on Cellular Customers Date: 2 Mar 1995 15:16:17 -0500 Organization: Panix in NYC, Admiral's Account In article Steve Samler writes: > What is the common practice today when someone applies for cellular > service? Credit check via one of the consumer credit agencies or via > D&B if a business is the applicant? Boy do I have stories to tell. My company, Parallel Technologies Corp., a NY State Subchapter S Corporation, tried to get cell service from Cell One/Boston and NYNEX. Heh. The results were so negative it was not even funny. Cell companies generally check for corporate listings on TRW or D&B; at least these two did. My company was not listed with either and was categorically denied credit (service) without a $400 security deposit. I told them I had both an AmEx and a MC in the company's name, a big company bank account, etc., etc., etc., but they did not care. I eventually talked to TRW: They said there's no way a company of my size would ever be listed in their computers. And they were unwilling to list me. But they were happy to send me and/or any possible creditors a sheet saying that I wouldn't be listed with them. End of story. Then I talked to D&B. They took some information and assigned me a DUNS number. Now I'm listed with D&B. However, they will not have any financial information on my company until a client requests the research be done (for some add'l fee). I eventually got fed up with it and asked a friend with a big company and a 4A1 rating with D&B if I could get service with a name of "Big Company, c/o Parallel Technologies Corp." That worked. Cell companies are really paranoid when it comes to small businesses with phones. My advice: get it with your personal credit and have your company reimburse you. Hope this helps. Doug Fields, http://www.interpage.net PGP key: "finger admiral@panix.com" ------------------------------ From: lincmad@netcom.com (Linc Madison) Subject: Re: Yes, Yung'uns. CNID -is- Logged at Your Local CO Organization: NETCOM On-line Communication Services (408 261-4700 guest) Date: Thu, 2 Mar 1995 21:24:50 GMT Ben Carter (bpc@netcom.com) wrote: > This reasoning assumes that caller ID is not available (as, for > example, in California) or that the telco records make it possible to > identify a caller when caller ID fails to do so. Also, I assume > everyone agrees that the privacy of the caller should not be a > consideration if a residential customer claims to be receiving > obnoxious calls. The privacy of the callee is certainly more > important than that of the caller in this case, and arguably so in all > cases. "Arguably" is a good word, because your assumed agreement does not exist. Making an anonymous telephone call is perfectly legal; it is only if the call is HARASSING or THREATENING that it is illegal, whether or not it is anonymous. Further, my right as a caller to expect privacy does not disappear simply because the person I called CLAIMS that my call was obnoxious, or even harassing or threatening. Releasing the number of the caller to the callee is not in any way necessary to deterring illegal nuisance calls. Another point to consider is your specification of "a RESIDENTIAL customer." The existence of such a right should not be contingent on class of service. Whatever rights I do or don't have for protection from nuisance calls should be the same on my phone at work as for my phone at home. Linc Madison * Oakland, California * LincMad@Netcom.com ------------------------------ From: gary.novosielski@sbaonline.gov Organization: Small Business Administration Date: Thu, 2 Mar 95 02:53:19 -0400 Subject: Re: Yes, Yung'uns. CNID -is- Logged at Your Local CO. Reply-to: gnovosielski@mcimail.com In Vol. 15, #120, Ben Carter wrote: > Also, I assume everyone agrees that the privacy of the caller should > not be a consideration if a residential customer claims to be > receiving obnoxious calls. The privacy of the callee is certainly more > important than that of the caller in this case, and arguably so in all > cases. Carter assumes too much. I, for one, would not be willing to toss the privacy rights of the caller on the trash heap merely on the strength of a "claim" by any given residential customer that they found the call "obnoxious." There has been ample discussion of all the reasons against Caller-ID, or at least in favor of blocking options. Many of these reasons are very "good" ones, and in some cases arguably protect the very lives of the callers involved. I won't rehash them all here. Now I ask myself if, potentially, for each person with one of those "good" reasons for protecting their privacy, there might not be someone else with a residential phone line whose ethics are so unbelievably twisted that they might actually stoop to "claiming" that at such-and-such a date and time they received an "obnoxious" call, and would Telco please supply them with the number. Anybody with any motive can claim anything; I'd want them to be able to prove it. Given the choice, I'd rather not have my privacy violated by anything short of a court order, thank you very much. And just so there's no confusion about how good a reason has to be before it's "good enough" in this context, I think the list of "good" reasons for privacy should should start with: 1. "Because I Feel Like It." GaryN GPN Consulting ------------------------------ Date: Thu, 2 Mar 95 09:16:47 EST From: hhs@teleoscom.com (Chip Sharp) Subject: Re: What is ESF and D4? If you are planning to run HDLC data over the full bandwidth of the T1 line (even in individual DS0s), then I would recommend an ESF line, since HDLC Flags, when used as idle code, can simulate Yellow Alarm on a D4 line. There are ways around it, but it must be taken into account. Hascall H. ("Chip") Sharp Teleos Communications, Inc. Sr. Systems Engineer 2 Meridian Road voice: +1 908 544 6424 Eatontown, NJ 07724 USA fax: +1 908 544 9890 email: hhs@teleoscom.com ------------------------------ Date: Thu, 2 Mar 1995 12:06:22 CST From: Mike Schomburg Subject: Re: What is ESF and D4? In Telecom Digest V15 #119, davethez@netcom.com (dave) writes: > When ordering a T1 line for data, the local fiber company wants to > know whether I'd like "ESF" or "D4". Could someone please explain > what these terms mean? You may already be aware that a T-1 circuit is a bi-directional serial connection, sending and receiving at 1.544 Mbps (million bits per second). Each second, 8000 data frames are exchanged (in both directions, send and receive). Each frame consists of 193 bits: 24 eight bit channels plus a framing bit. ESF and D4 refer to the "framing format" used on any particular T-1. When a T-1 starts up, or "frames", it picks a bit going past and assumes it is the framing bit. Every 193rd bit after is examined and compared to an expected pattern. As soon as the pattern is violated, the next bit in sequence is chosen as the framing bit and the comparison begins again. This process is continued until the actual framing bit is found and the line established, or too many errors are encountered and the line fails to start. Once framing is established, it becomes possible to locate the 24 data (or voice) channels and exchange information. D4 is probably still the most common framing format (lets not start that again), but ESF is coming up fast. D4 simply allows the terminal gear to locate the payload channels, plus a very crude ability to signal the far end that problems have interrupted the line (when appropriate). ESF (Extended Super Frame) also "frames" the data, but additionally includes tha ability to send operational messages end-to-end, and provide a level of line quality reporting. This is done by organizing groups of 12 frames into "super" frames. With processing power, the line can stay framed while half of the framing bits are borrowed to form a message channel. A CRC scheme is used to calculate line quality, detecting about 93% of error conditions. There are at least two common flavors of ESF, a proprietary AT&T scheme and an ANSI scheme, T1.403 I believe. Be sure you know which one your terminal gear supports. If you are running data, you may also want to check on the "line coding" format, AMI (Alternate Mark Inversion) or B8ZS (binary 8 zero superssion). In the past, all T spans were AMI, which limited the ability to send strings of zeros. All "ones" were sent as alternating polarity pulses (to keep the DC component low) on the line, and "zeros" were sent as the absence of pulses. Obviously, too many zeros and the line would quickly lose synch. B8ZS is a scheme to avoid the line dropping while sending unlimited zeros. For reasons that I have not gone into, if you want to be able to use the full 64kbps capacity of each channel (instead of just 56kbps) then you want B8ZS. Hope this helps. Mike D. Schomburg Network Manager, Continental Cablevision 708 834 4239 Chicago region schombur@continental.com "linux - the choice of a GNU generation" ------------------------------ From: david.taylor@ntc.nokia.com (David S. Taylor) Subject: Re: Anyone Heard of SMR - Specialized Mobile Radio? Date: 2 Mar 1995 14:47:15 GMT Organization: Nokia Telecommunications, Inc. In article , murrays@clipper.robadome.com (Scott Murray) says: > I was wondering if anyone had any info on SMR -- Specialized Mobile > Radio. I have been approached by a company in Florida to buy an SMR > channel. The channel is in the 851-866Mhz range and is used by > companies to provided cellular like service at a cheaper rate. The > channels are supposedly given out by the government on a first come > first serve basis, but this company wants to charge by $3500 to file > all the paper work and guarantees me a channel or my money back. In my opinion: Chances are 99+% that this is a scam. There have been several companies that have been busted for this type of activity. Some of the "offices" were nothing more than boiler room operations. I've even seen a story on one of the news magazines. I used to live in Southern California, and they busted a couple of operations out there. For some reason, lots of phone scam folks set up show in southern CA, probably in hopes they will sound successful and legit. As far as the filing fee, I think the FCC charges a couple of hundred dollars. The first come, first serve basis might also be in question. I know the FCC has had a freeze on some SMR applications. Don't know if it was all, or just a subset. From a technical point of view, one channel does not make an SMR system. They must have a site in mind for the license. If you are still intersted in checking into this, ask them to send you a copy of the application form, showing the site coordinates and antenna elevation. Ask them about the channel loading plans and if they plan on filing for slow growth vs. normal. This has to do with how long they have to load up their channels with users. I think you have to reach around 75% loading in under five years, but I can't remember the exact details. My guess is they won't be able to answer your questions. Their money back guarantee is only good if you can find them. > Supposedly once you have a channel you can rent it out or sell it to > the regionaly operators and they are very anxious to get these extra > channels. The have been able to convert these old style radio > dispatch towers into digital towers that provided phone, paging and > fax service at a fraction of the cellular cost and the towers cover a > larger range. Think about it, wouldn't it just be easier for these carriers to apply for the channels themselves. Why would they want to pay a premium to you, if they could just fill out the same paperwork. > My questions are these: > Is this really a good investment? Are these channels really in demand > by companies like Nextel, CenCall, DialPage etc.? Is it worth going > through this company or are there cheaper ways to get a channel? Nextel is a big player in the market. I bought some of their stock while I was at my last job. Then my new job sent me overseas for a few months and the Nextel stock dropped by about 70%. Guess I hold it for a while. From what I understand, Motorola is having some delays with their MIRS technology. I've seen a demo at my last job and it looks like it has potential, especially for wide are dispatch operations. I won't comment on the phone call quality becuase I'm now biased, since I'm in the PCS business. David S. Taylor Tel. +1 817 491-5832 Engineering Services Fax +1 817 491-5888 Nokia Telelcommunications, Inc. david.taylor@ntc.nokia.com ------------------------------ From: russell@trussell.pdial.interpath.net (Travis Russell) Subject: Re: Anyone Heard of SMR - Specialized Mobile Radio? Date: Thu, 2 Mar 1995 21:22:00 +0000 Organization: Travis Russell Reply-To: russell@trussell.pdial.interpath.net (Travis Russell) In article , murrays@clipper.robadome.com (Scott Murray) writes: > I was wondering if anyone had any info on SMR -- Specialized Mobile > Radio. I have been approached by a company in Florida to buy an > SMR channel. The channel is in the 851-866Mhz range and is used > by companies to provided cellular like service at a cheaper rate. > The channels are supposedly given out by the government on a first > come first serve basis, but this company wants to charge by $3500 to > file all the paper work and guarantees me a channel or my money back. Sounds a little like a scam to me. I have been approached by a number of companies wanting me to buy into wireless cable as well, for a paltry sum of $10,000. > Supposedly once you have a channel you can rent it out or sell it to úÿ > the regionaly operators and they are very anxious to get these > extra channels. The have been able to convert these old style > radio dispatch towers into digital towers that provided phone, paging > and fax service at a fraction of the cellular cost and the towers cover > a larger range. I don't know that there are any companies looking to buy "second hand" SMR channels these days. I am probably wrong here, but from what I have seen in the market, Nextel has all the channels it needs for now, and if they are looking for more, they will go to the FCC to get them. > My questions are these: > Is this really a good investment? Are these channels really in demand > by companies like Nextel, CenCall, DialPage etc.? Is it worth > going through this company or are there cheaper ways to get a channel? Before I would spend any money, I would call some of these companies and ask them myself! If this is a great bargain, and these companies are really demanding these channels, how come this company selling them to you doesn't go after Nextel, CenCell or Dialpage themselves? I would think they could get a lot more money from selling it directly to these companies. I may be offbase here, so someone jump in and correct me if I am wrong. I think you are getting ripped off. Travis Russell russell@trussell.pdial.interpath.net Author of "Signaling System #7," McGraw-Hill ------------------------------ From: russell@trussell.pdial.interpath.net (Travis Russell) Subject: Re: Information Wanted on Hotel Telephone Billing Date: Thu, 2 Mar 1995 21:30:52 +0000 Organization: Travis Russell Reply-To: russell@trussell.pdial.interpath.net (Travis Russell) In article , cacclin@vanbc.wimsey.com (Stephen Cacclin) writes: > My question is: What is the best method to calculate the telephone > charge? Whatever rate you want! Usually, there is a table that is built that has default rates. These are not exact (since the rates change faster than my underwear) but they do not need to be close. The intent is to get close to the rate as possible. A markup is then set for each type of call (like 800, local, etc). I used to markup hotel calls as much as 200% (depending on the hotel). If the hotel is a five star hotel, they can get away with big markups. If it is a Holiday Inn, then they have to set their sites lower. > I guess I am looking for some sort of standardized rate table for > North American long-distance. Does such a thing exist, and if so, is > it available on the net? Someone please say yes, as I am not up > to entering these rates by hand ... > [TELECOM Digest Editor's Note: Just charge as much as you think you > can get away with; that's what the other hotels do. PAT] I used to tell my customers they could pay for their call accounting equipment within the first year of operation! Hows that for profits! Travis Russell russell@trussell.pdial.interpath.net Author of "Signaling System #7," McGraw-Hill ------------------------------ From: jdearing@netaxs.com (John Dearing) Subject: Re: Does Bridge Affect Modem? Date: 2 Mar 1995 04:14:42 GMT Organization: Netaxs Internet BBS and Shell Accounts Ted Shapin (tshapin@kaiwan.com) wrote: > I have two copper pairs coming to my residence and need a third line. > If it is bridged between the two pairs, what effect will it have on my > use of a v.32bis modem on one of the copper pairs? Something doesn't seem right here. You need a copper pair for *each* telephone line that's delivered. You can't "bridge" a line across the two other existing pairs. What *could* be done is that a device called a SLC-1 might be installed. It allows two lines to operate over a single pair. The device has two "ports". One is called the "physical" and the other is called the "theoretical" or "derived" port. I would recommend that you try having the modem on the physical side. The derived side (since it is a "carrier" type operation) doesn't always work really well with modems. Telco's usually hate to install these beasts. They have batteries that need to be replaced every so often, even though they recharge when the physical line is idle. I've only seen them installed twice. Once was a situation where there were *NO* pairs left in a cable. The only way to get a customer back in service was to put up a SLC-1 out at the terminal and hook the two loops into it. It was a temporary measure until a work order could be issued to rehab the cable run. The other time was for an Arbitron line in a house out in the 'burbs that only had a single pair buried loop feeding it. The line was a temporary line for about three to six months after which it would be disconnected. The decision was made to SLC-1 the Arbitron line rather than have to run a new buried loop through the woods to the house (that was partially set *into* a hill). John Dearing jdearing@netaxs.com ------------------------------ Date: Thu, 2 Mar 1995 22:53:15 -0500 From: KJSHEA@aol.com Subject: Re: Free Expression and the Information Superhighway Some excellent points were brought out in defense of free expression on the "Information Superhighway", as it is being referred to. Unfortunately, this is another vehicle that enables the "bad" few to access and create problems. As it stands now, free expression here has created wonderful outcomes and innovative ideas, from a business perspective. Once regulations begin ... they don't seem to stop. The "think about it before you say it" will apply, subsequently, limiting those "edge of the cliff" ideas and discussions which we on the "I-S-H" enjoy. Restrictions, like in the past, will affect all who participate in this. The telecom industry, as a whole, needs to address this issue or accept the realization that the fear of regulation, censorship or moderation will affect the growth of the entire industry. We all know what regulation can do, let's keep on our toes when dealing with this issue. Very Concerned, Kevin J. Shea, Director Telecom Research Services kjshea@interactive.net or KJSHEA@aol.com ------------------------------ From: stans@panix.com (Stan Schwartz) Subject: Re: 500 Place-A-Call Working Date: 2 Mar 1995 23:53:11 GMT Organization: PANIX Public Access Internet and Unix, NYC > [TELECOM Digest Editor's Note: Since you mentioned 'Navigator', that is > one part of 500 service many users are not familiar with. Would you > please send in a short explanation of it? PAT] Why sure ... (Quoting from the True Connections book) "With Call Sequencing, your calls will find you just about anywhere. Now, each call can ring in your office, then in your car, then at your home -- or virtually any other place you choose, up to three destinations, as long as the location can be dialed directly, in the U.S., Puerto Rico, the Virgin Islands, and over 200 countries internationally. The destinations you select are referred to as your Reach List. Right now, your Reach List contains your billing telephone number, or, if applicable, your cellular phone number." ---------------- It's programmable rollover, up to three phone numbers plus one designated as the "Final Stop" (usually you would have an answering machine or voice mail at the Final Stop). You can control how many rings each destination will receive before switching to the next number in the list, and you can change the list as often as you want. You can also temporarily override the list without purging it (for vacations, etc.). Eventually, the reach list will be time-sensitive (programmable) so that you can get calls in your office during the day only, or at home only at night. I'm STILL lost on the CIID/891 cards, though! Stan [TELECOM Digest Editor's Note: I feel like an idiot. The above is *exactly* what I have on my 500 service, but I did not recognize the name 'Navigator' for that part of the package. I guess I should go back and read my copy of the 500 User Manual also. PAT] ------------------------------ From: fgoldstein@bbn.com (Fred R. Goldstein) Subject: Re: What is a Digital PBX? Date: Thu, 2 Mar 1995 23:56:21 GMT Organization: Bolt Beranek and Newman Inc. In article noah@rain.org (Matt Noah) writes: > What is the definition of a "digital" PBX? A "digital PBX" is one whose internal switching matrix is digital. That is, the analog line interfaces, if they exist, have codecs which convert the signal to digital form for switching purposes. Digital PBXs came out in the 1970s; it was several years before they had digital line interfaces. Today, virtually all PBXs (save some tiny ones) are digital, using standardized 64000 bps voice channels. ------------------------------ From: russell@trussell.pdial.interpath.net (Travis Russell) Subject: Re: What is a Digital PBX? Date: Thu, 2 Mar 1995 21:38:02 GMT Organization: Travis Russell Reply-To: russell@trussell.pdial.interpath.net (Travis Russell) In article , noah@rain.org (Matt Noah) writes: > What is the definition of a "digital" PBX? > Assuming an analog PBX is one in which the trunk lines are strictly > analog, e.g. E&M, Ground Start, is a "digital" PBX one in which the > trunk lines all carry PCM voice with digital signalling? If so, what > type of digital signalling? Is it T1? Is it ISDN? Is it something > other than T1 or ISDN? Is it combinations of various digital standards? Yes! All of the above. A digital PBX provides digital phones (usually over one or two pair wire) with lots of features only possible through digital phones. In addition, they are usually capable of interfacing directly to any T-1, ISDN or other facility. They also support analog trunks. Some can even switch data with the voice (after all, everything is digital). I used to work on a system that actually converted the voice to digital inside the telephone, and packetized the voice. There was a second part in the packet reserved for data transmission. Pretty slick system, and had lots of neat features. Travis Russell russell@trussell.pdial.interpath.net Author of "Signaling System #7," McGraw-Hill ------------------------------ From: co057@cleveland.Freenet.Edu (Steven H. Lichter) Subject: Re: The Unintentional Date/Chat Line Date: 2 Mar 1995 08:16:46 GMT Organization: Case Western Reserve University, Cleveland, Ohio (USA) Some time ago they also used the loop around numbers to talk back and forth. I don't know what we did, but I know we modified the circuits to prevent it. It was a long time ago, my mind is going because of deregulation. Sysop: Apple Elite II -=- an Ogg-Net Hub BBS Home of GBBS/LLUCE support (909) 359-5338 12/24/14.4 V32/V42bis [TELECOM Digest Editor's Note: I've heard complaints that the phone system in the USA had gone to hell because of deregulation ... this is the first time I've heard anyone say his mind went the same way for the same reasons. Or is that not what you meant? PAT] ------------------------------ Date: Thu, 2 Mar 95 17:12:34 PST From: moinz@la.AirTouch.COM (Zuhair Moin) Subject: Computer Modeling Software For AM Tower/Antenna Studies Is there modeling software that can be used to construct an antenna system for AM tower studies for Cellular deployment effects? The one that I have heard about is called MININEC, originally developed for the Naval Ocean Systems Command, and is in the public domain. How can I get this software? Thanks, Zuhair Moin ------------------------------ From: Gene Retske Subject: Re: Saying Hello in Other Languages - Summary Date: 3 Mar 1995 01:03:17 GMT Organization: Tachyon Communications Corporation PAT - You forgot the New York "Talk to me!" Gene Retske [TELECOM Digest Editor's Note: I thought the New York answer phrase was "It's your nickle!" (As in, you paid for the call, go ahead and speak.) PAT] ------------------------------ End of TELECOM Digest V15 #130 ******************************