Received: (from ptownson@localhost) by massis.lcs.mit.edu (8.9.1/8.9.1) id QAA04246; Mon, 26 Apr 1999 16:53:16 -0400 (EDT) Date: Mon, 26 Apr 1999 16:53:16 -0400 (EDT) From: editor@telecom-digest.org Message-Id: <199904262053.QAA04246@massis.lcs.mit.edu> X-Authentication-Warning: massis.lcs.mit.edu: ptownson set sender to editor@telecom-digest.org using -f To: ptownson Subject: TELECOM Digest V19 #59 TELECOM Digest Mon, 26 Apr 99 16:53:00 EDT Volume 19 : Issue 59 Inside This Issue: Editor: Patrick A. Townson Adaptive Echo Canceler (Electronics) (Bruce Henderson) Re: New Billing Charge: Local Number Portability (Will Roberts) Re: Last Laugh! Not a Thing For the House of God (Chris Gettings) 4+8? (was Re: The NANP Has 8+ Years to Go) (John David Galt) Re: The NANP Has 8+ Years to Go Says NANPA (Craig Macbride) Re: European-Wide Country Code of +388: How Implemented (Peter Corlett) Re: European-Wide Country Code of +388: How Implemented (Richard D G Cox) Rate Rationalization, was: Re: NANP Has 8+ Years to Go (Danny Burstein) Spammer's 800 Number Has Fake SIT Tones? (Ray Normandeau) Pac Bell Plan For National 41l Calls OKd (Monty Solomon) Re: Dialtone in Different Countries (Craig Macbride) ADC/MIND CTI Press Release (Andrea Dray) 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 networks such as Compuserve and America On Line, and other forums. It is also gatewayed to Usenet where it appears as the moderated newsgroup 'comp.dcom.telecom'. TELECOM Digest is a not-for-profit, mostly non-commercial educational service offered to the Internet by Patrick Townson. All the contents of the Digest are compilation-copywrited. You may reprint articles in some other media on an occassional basis, but please attribute my work and that of the original author. Contact information: Patrick Townson/TELECOM Digest Post Office Box 765 Junction City, KS 66441-0765 Phone: 415-520-9905 Email: editor@telecom-digest.org Subscribe/unsubscribe: subscriptions@telecom-digest.org This Digest is the oldest continuing e-journal on the Internet, having been founded in August, 1981 and published continuously since then. Our archives are available for your review/research. URL information: http://telecom-digest.org Anonymous FTP: hyperarchive.lcs.mit.edu/telecom-archives/archives (or use our mirror site: ftp.epix.net/pub/telecom-archives) Email <==> FTP: telecom-archives@telecom-digest.org Send a simple, one line note to that automated address for a help file on how to use the automatic retrieval system for archives files. You can get desired files in email. ************************************************************************* * 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. * ************************************************************************* In addition, a gift from Mike Sandman, Chicago's Telecom Expert has enabled me to replace some obsolete computer equipment and enter the 21st century sort of on schedule. His mail order telephone parts/supplies service based in the Chicago area has been widely recognized by Digest readers as a reliable and very inexpensive source of telecom-related equipment. Please request a free catalog today at http://www.sandman.com --------------------------------------------------------------- Finally, 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. Please make at least a single donation to cover the cost of processing your name to the mailing list. 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: Bruce Henderson Subject: Adaptive Echo Canceler (Electronics) Date: Mon, 26 Apr 1999 07:43:01 -0700 Organization: BH & Assoc CTE [TELECOM Digest Editor's Note: I am not certain if the diagram below came out exactly as the author intended or not. Email delivery does strange things now and then. I also added the 'pre' and '/pre' commands for the benefit of those people who get the Digest in HTML format, such as at http://telecom-digest.org/TELECOM_Digest_Online PAT] 
Hi,

I am experimenting with the following telecommunications circuit:

Symbols:
-[[]]- <- resistor       ---o--- connection

  /|+---
(  |  <- op amp
  \| - --

Echo canceller circuit - Ampliflies input, Mixes output, attenuates output
feedback "Echo" (used in electronic analog telephone sets):

                      -------------------[[]]-------------
                     |                100K                   |
                     |                        1k                |
                     |        /|+---------[[]]------------o--------------
Input  --------o-----( |            Inp Gain                          |
(-Output)               \|- ------------o-------                        |
                      OP1                    |         |    51K            |
                                         51K  |         ----[[]] ----
o -------  Output + Input (Tel co)
                                     ----[[]]---                         |
|
               600              |  Echo                          \/        |
Output --[[]] --- -|\        |
|       900K

             | )----o---[[]]-------------------------------o-----[[]]-------
                    ---+|/           Source Z
load ZL   |
                   |                   600
\/
                  \/    OP2

Could someone e-mail me the circuit that maintains the Echo attenuation
while the load impedence (ZL) is independantly varied?

Thanks,

exnoop@msn.com
------------------------------ From: oldbear@arctos.com (Will Roberts) Subject: Re: New Billing Charge: Local Number Portability Date: Mon, 26 Apr 1999 00:15:23 -0500 Organization: The Arctos Group - http://www.arctos.com/arctos black@csulb.NOSMAP.edu (Matthew Black) writes: > GTE California has started billing this residential customer $0.38 for > local number portability. I never requested any such service and am > curious if this is some new universal fee. Local Number Portability (LNP) is the FCC-mandated ability to keep your same telephone number even if you switch Local Exchange Carriers. The idea is that no one would leave the incumbent RBOC if they had to change to a new phone number. I'd guess that this charge is a result of GTE attempting to recover the cost of providing LNP. I'd be curious if this is an across-the-board charge on all customers or something related to your having taken your phone number to a different local telco. If it's an assessment to keep your phone number when changing carriers, it sure seems like a dis-incentive to make a change unless your new phone company charges that much less. What is also nasty about what you describe is that making an LNP change is really a one time cost of reprogramming the database and not something that should result in a monthly charge forever and ever. Regards, Will Roberts The Old Bear ------------------------------ Date: Mon, 26 Apr 1999 00:04:39 -0400 From: Chris Gettings Subject: Re: Last Laugh! Not a Thing for the House of God I am a pilot and have used a cell phone in light aircraft and I can assure readers that they are a serious safety hazard. I can't understand how they could interfere with brakes which are hydraulic, except perhaps if they were computer controlled anti-lock brakes -- common on bigger planes -- and even these are designed such that if the computer fails, they revert to normal brake actuation. In flight, however, even while just powered on and not transmitting, I watched a handheld analog cell phone cause erroneous indications on the directional gyro of greater than 90 degrees. I learned this while attempting to land in instrument conditions, the worst possible time to conduct these experiments. I wondered why the radio and vacuum driven flight and navigation instruments did not agree and found my cell phone on in my pocket. Switching it off caused the gyro to return to the proper indication. The hair on the back of my neck is *still* standing up ... Chris ------------------------------ From: John David Galt Organization: Diogenes the Cynic Hot-Tubbing Society Subject: 4+8? (was The NANP Has 8+ Years to Go) Date: Mon, 26 Apr 1999 02:05:54 GMT Quoth John R. Levine: >> http://www.nanpa.com/pdf/NANP_Exhaust_Study.pdf >> VERY informative ... they now project total exhaustion between 2006 >> and 2012, with their best guess being 2007... 8 1/2 years to go! NO >> FCC action recommended regarding 10-D or 11-D dialing yet. No timetable >> for expansion yet. No FCC mandate for implementing expanding dialing >> patterns from 3+7 to 4+8 with a deadline for launch. How about >> deciding IF 4+8 will be the solution? > Of course it won't be the solution. There are plenty of unused ten > digit phone numbers. I like the idea of a 12 digit total length, but it seems to me it would make sense to make each of the parts variable-length. If we allow (for example) either 2+10, 3+9, or 4+8, then major cities can go 2+10, allowing everyone to keep their existing 10-digit numbers (while still having all _kinds_ of room for expansion). Here is one way the process could go (all at once, no waiting needed). 1) Assign area code 99 as a "helper code." Dialing 1 + 99 + an old 10-digit number would get you instructions on the new way to call that number. (This could also be used as the temporary area code for areas which haven't yet been updated to the new system, but if such areas exist it will be for political reasons.) 2) Assign 29, 39, ..., 89 to the seven biggest cities going 2+10. (If 37x, 52x, and 96x aren't used by then, we can use those codes this way also.) Each of these new codes would include an entire metro area, except possibly across state/national lines (that's a political decision). 3) Areas going 3+9 would simply suffix two digits onto all existing numbers (I suggest 00). 4) Areas going 4+8 would simply append a zero onto the old area code and another onto the number. Similarly, areas going 5+7 would append 00 onto the area code. 5) 800 and 900 services would change to 80 and 90 + ten digits. In these cases I would convert all existing numbers as if they were going 3+9 (keeping the zero in third position!), but allow holders of vanity numbers to choose the two digits that get added at the end. The same goes for 500 and 700 numbers if they still exist. We could expand 888, 877, 866, etc. the same way, but I think it would be cleaner to make those subscribers move into the "80 + ten digits" space, perhaps as 80 + the old 10-digit number. 6) Once the cutover is made, dialing a number by any of the old methods (7 digits, 10 digits, 1+10 digits, or 0+10 digits) CANNOT go through to the wrong place. It will do the following: You dialed (and The area you are dialing changed over to: it was correct 2+10 3+9 4+8 5+7 before the cut): 7 digits dead [1] dead [1] dead [1] success! 10 digits success! intercept intercept intercept [2] [2] [2] 1 + 10 digits dead [1] dead [1] dead [1] dead [1] or 0 + 10 digits [1] Switch will expect more digits. [2] I assume the old area code wasn't assigned as a prefix within itself. If it was, it should be changed before cutover. John David Galt ------------------------------ From: craig@rmit.EDU.AU (Craig Macbride) Subject: Re: The NANP Has 8+ Years to Go Says NANPA Date: 26 Apr 1999 13:35:31 GMT Organization: Royal Melbourne Institute of Technology, Melbourne, Australia. Eric@AreaCode-Info.com (Eric B. Morson) writes: > No FCC mandate for implementing expanding dialing > patterns from 3+7 to 4+8 with a deadline for launch. How about > deciding IF 4+8 will be the solution? How about cutting loose the non-US members (possibly not Canada, but at least the Caribbean countries) of the NANP at the same time, thus giving more numbering space to the US and stopping all the fraud schemes based on confusing people into calling numbers they believe are in the US which are in fact in other countries? (For any legitimate businesses in these countries, a 4+8 NANP number will be about as long as international-prefix + country-code + local-code number and require hardware changes at their end that would be unnecessary if they kept their current local numbers and just moved to having their own country code.) > How can planning wait any longer, considering how much hardware, > software, education, politics, and regulation needs to be completed, and > only 8.5 years to go? The system here is far less messy in its structure, due to much greater regulation and far fewer competitors for domestic calls, but the changeover to 8 digit numbers took the better part of 2 years. All of the planning and most of the hardware needs to be in place at least a couple of years before the deadline. The education, politics and regulation part needs to be completed even sooner. Craig Macbride URL: http://www.bf.rmit.edu.au/~craigm "It's a sense of humour like mine, Carla, that makes me proud to be ashamed of myself." - Captain Kremmen ------------------------------ From: abuse@verrine.demon.co.uk (Peter Corlett) Subject: Re: European-Wide Country Code of +388: How Implemented, if So? Date: 26 Apr 1999 13:28:35 GMT Organization: B13 C*b*l Linc Madison wrote: > For instance, London numbers would be +344 20 nxxx.xxxx, so you could dial > 1-44-20-nxxx.xxxx. To call Dublin, you would dial 1-53-1-nxx.xxxx. > Pan-European toll-free numbers would be 1-888-nxx.xxx[x][x]. Premium > numbers would be on 1-900. This would take some doing. The UK uses 1xx and 1xxx codes for a lot of things. They're commonly used for Indirect Access (carrier selection like 10xxx) codes, as well as being contact numbers for the operator, directory enquiries and emergency services. Where would these numbers go to? Your example codes are already partly used: 144 is for BT Chargecard. 153 is International Directory Enquiries. 1888 is currently free, but is clearly reserved for Indirect Access (it's surrounded by others that are allocated) and 190 is used for the Telemessage service. I fail to see what is wrong with +800 for EU-wide freephone anyway, since it's already used for this purpose. [...] > Perhaps Europe could become +0 when that range opens up for assignment > in the not-too-distant future "000" is used as a special code by BT to show an agreement to the higher charge than for a standard (but not guaranteed 64k end-to-end) "00" call. http://www.verrine.demon.co.uk/ B13 Cabal Member Cuius rei demonstrationem mirabilem sane detexi hanc marginis exiguitas non caperet ------------------------------ Date: Mon, 26 Apr 1999 13:31:00 BST From: Richard@office.mandarin.com (Richard D G Cox) Subject: Re: European-Wide Country Code of +388 Reply-To: Richard@office.mandarin.com In Telecom Digest V19, #53 <199904241756.NAA06308@massis.lcs.mit.edu> Linc Madison said: > +388 was part of a doomed plan to renumber all of Europe under the > single country code +3. It may have been that at one time, but the current proposals are quite different. +388 is now intended to be an overlay, which would provide users with "European" phone numbers instead of numbers based out of the country where the user is actually located. Some might think of +388 as being more a form of "politically-correct" number! +388 would include Pan-European numbers for response to TV advertising, as well as for a European 900 service. The original plan to use +3 800 was indeed squashed by the allocation by ITU-T of country code +380 to the Ukraine, and I recall there was heated correspondence at the time between the various parties involved over that allocation. The present view seems to be that +800 is much easier to "sell" as a Freefone concept than +3 800 or +388 800, so it seems there will be no European Freefone. > All very American looking; rather surprising given the anti-American > bent of most telecomms Eurocrats. Not really; there were no proposals to change to 011 for international! > The Ukraine is certainly big enough that it would have deserved a > two-digit code (unlike +45 Denmark, +64 New Zealand, +65 Singapore, ITU-T policy is that all new country code assignments will be three-digit. > but the people who created the plan didn't adequately think through the > transition required to get there. More that they didn't realise the level of opposition there would be from the "member states" to being required to change their phone numbers just to please Brussels. Ironically, most of those "member states" have gone through (at least) one major renumbering since then of their own volition. Their plan wasn't particularly sound, partly because the balance of the numbering density/utilisation through Europe would have become even worse than it was before, and partly because it failed to look to the future of how each country wanted to develop its own numbering scheme. But it was *their* plan, and that was why it went forward. Suggestions of how the plan might be improved, both to make it more politically acceptable - and also to make it more sound from a numbering standpoint - were rejected with the standard error cause code of "NIH" - "Not Invented Here". > Perhaps Europe could become +0 when that range opens up for assignment That could certainly be attractive, and providing it was implemented in an organised way should return two decades (+3 and +4) to the ITU-T for reassignment -- in other words giving them a "two for one" deal. However it would not be enough to just migrate the existing codes in the way you described; there would have to be some additional restructuring as well taking into account all the numbering developments within each country. Also, since the political borders of "Europe" are changing all the time, a decision would have to be taken about countries which have "come out" of "+7" - as Latvia has - or might do so in the (un)foreseeable future. But I do still doubt whether the "member states" would accept any plan imposed by the Commission, unless they were effectively forced to so do. Richard D G Cox Mandarin Technology PO Box 111 PENARTH CF64 3YG, UK: Tel: +44 29 2031 1131 Senders of genuine e-mail should omit the word "office" from our address. ------------------------------ From: dannyb@panix.com (danny burstein) Subject: Rate Rationalization, was: Re: NANP Has 8+ Years to Go Date: 26 Apr 1999 11:22:14 -0400 In johnl@iecc.com (John R. Levine) writes: > NANP Exhaust Study..published www.nanpa.com/pdf/NANP_Exhaust_Study.pdf > Of course it won't be the solution. There are plenty of unused ten > digit phone numbers. Unfortunately, insane amounts of them are locked > up in 10,000 number blocks that CLECs have reserved so every CLEC has > a prefix in every rate center in which they might ever offer service. > (I don't blame the CLECs for this, the way the system is set up, a > CLEC puts itself at a significant disadvantage if it doesn't hoard > numbers like this.) Which brings up the simpler solution, but one, alas, which the ILECS won't like, namely a rationalization, and _reduction_, of the rate structures. (Has anyone else noticed that while long distance phone rates are significantly lower than 15 years ago, there hasn't been any similar drop in the local ones?) Take the NYC area, for example. While the city itself is kind of sensibly arranged (all calls within the five boroughs - very roughly 4 million numbers) are considered 'local' [1], that's not the case in the suburbs. [1] In this part of the world, local means that residential calls are charged a nominal 10 cents/call, but that they are otherwise untimed. Calls outside your local area are charged per minute, with the exact amount determined by distance. Business customers all pay roughly 1.5 cents/minute. And isdn, err... In the eastern suburbs of Nassau and Suffolk Counties (currently area code 516), there are three separate rate zones. So anyone wishing to set up a 'local' number for customers must get at least three separate exchanges. Additionally, the ILEC has set up a kind-of 'unlimited' (no charge/call) offering for very, very, local calls (although, to no one's surprise, not in NYC itself). These districts are much smaller than the main ones I mentioned in the above paragraph, so if your ILEC wanted to set up 'local' numbers for all _these_ people, you'd be talking something like two dozen separate exchanges. If the ILECS would get rid of this mindset and expand 'local' calling to include the entire district, then a _huge_ amount of the pressure for additional exchanges would disappear overnight. (I'm hoping that this will happen without them ... I suspect we're well on the way. Thanks to two-way cable modems, *dsl connectivity, and simple plug-in voice-over-ip 'phones', I'm hoping that within a year we'll see [in effect] unlimited 'on-net' calls, anywhere in the nation, for $50/month or so, completely bypassing the ILEC local loop. You heard it here first ... "you give us $50/month, we give you the nation") Knowledge may be power, but communications is the key dannyb@panix.com [to foil spammers, my address has been double rot-13 encoded] ------------------------------ From: Ray Normandeau Subject: Spammer's 800 Number Has Fake SIT Tones? Date: Mon, 26 Apr 1999 17:04:30 GMT Organization: Deja News - The Leader in Internet Discussion Benchmark Print Supply, a big time spammer previously had an 800 number in his ads. This can be ascertained by searching the Dejanews archives of OLD messages. Search for: "800-391-4677" His current spam has 770 area codes. An attempt to call his 800-391-4677 number for removal from his list produces a very interesting response. 800-391-4677 is answered by what appears to be an answering machine giving SIT tones and telling the caller to try again. Could this be to discourage callers from pay phones? Any opinions? Is it really an answering machine? -----------== Posted via Deja News, The Discussion Network ==---------- http://www.dejanews.com/ Search, Read, Discuss, or Start Your Own ------------------------------ Date: Mon, 26 Apr 1999 04:08:15 -0400 From: Monty Solomon Subject: Pac Bell Plan For National 41l Calls OKd Deborah Solomon, Chronicle Staff Writer Friday, April 23, 1999 http://www.sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/1999/04/23/BU64726.DTL ------------------------------ From: craig@rmit.EDU.AU (Craig Macbride) Subject: Re: Dialtone in Different Countries Date: 26 Apr 1999 13:14:24 GMT Organization: Royal Melbourne Institute of Technology, Melbourne, Australia. lucio1974@my-dejanews.com (Lucio Maggioli) writes: > I was wondering what kind of dialtone (continuous or stuttering) is > used in different countries of the world. Does anyone have information > about this subject? The telephone books here list the different dial and busy tones for each country along with their country codes and area codes. Surely this list is available elsewhere too? (One would hope phone books would generally list this, as the tones vary a great deal from place to place.) Craig Macbride URL: http://www.bf.rmit.edu.au/~craigm "It's a sense of humour like mine, Carla, that makes me proud to be ashamed of myself." - Captain Kremmen ------------------------------ From: Andrea Dray Subject: ADC/MIND CTI Press Release Date: Mon, 26 Apr 1999 10:19:24 +0300 ADC Telecommunications and MIND CTI Join to Provide Operations Support Systems (OSS) for Voice over Internet Protocol (VoIP) Solutions April 26, 1999 Minneapolis, MN and Yoqneam, Israel - ADC Telecommunications, Inc., (NASDAQ: ADCT; www.adc.com) and MIND CTI Ltd., Yoqneam, Israel, have signed an agreement by which ADC will offer operational support system (OSS) for voice over Internet protocol (VoIP) solutions for telephony providers and enterprises. ADC will supply MIND-iPhonEX* IP telephony billing & customer care and associated professional services which will complement ADC's ability to deliver full VoIP solutions to the marketplace. To remain competitive, it is critical that telecommunications providers are able to migrate to and offer VoIP to their customers. "This agreement is yet another positive step in the growing relationship between ADC and MIND," said Lior Salansky, vice president of business development for MIND CTI. "MIND is enthusiastic about working with ADC on VoIP Billing. We are convinced that our position in the US market will be strengthened by this relationship and that our customers will benefit from the enhanced installation and integrated services ADC will supply nationwide." Jay Swearingen, president of ADC's Complex Solutions division within the Integrated Solutions Group, said "As a premier supplier of OSS solutions to telecommunications service providers, ADC is excited to add billing & customer care solutions built with the MIND-iPhonEX product to the ADC OSS offerings. Until now, a process to bill customers for making internet calls was not available. This solution will generate greater revenues for our customers through its ability to bill and keep records. By supplying solutions including the MIND-iPhonEX product we enable our customers to quickly enter the VoIP market." MIND-iPhonEX is a carrier grade, real time billing & customer care system for the emerging VoIP industry. With one of the largest installed bases worldwide, MIND-iPhonEX has rapidly become the billing and customer care system of choice for leading telecommunications companies like Deutsche Telekom, France Telecom, Telia Light of Sweden, Internet Service Providers (ISPs) and Internet Telephony Service Providers (ITSPs). MIND-iPhonEX is integrated and installed with leading gateway/gatekeeper vendors such as Ascend, Cisco, Lucent, Netspeak, Nokia, VocalTec, and others. The award winning MIND-iPhonEX (1998 Product of the Year in Computer Telephony, CTI and Internet Telepony magazines) provides a fully redundant solution including a fail-over mechanism, database replication and no single point of failure to insure highly reliable service to millions of customers. The system handles both prepaid and post-paid billing, creation and management of prepaid calling cards, real-time cut-off of calls, individualized customer rate tables, and flexible fax charge options. MIND-iPhonEX support systems provide call management reports, traffic analysis (monitoring the load on each gateway and line) and keeping track of excessive use, including fraud alarms. Web-based customer care and subscriber verification of real-time balance and call details are also available. ADC Telecommunications, Inc. is a leading global supplier of voice, video and data systems for telephone, cable television, Internet, broadcast, wireless and private communications networks. ADC's systems enable local access and high-speed transmission of communications services from providers to consumers and businesses over fiber-optic, copper, coaxial and wireless media. Headquartered in Minneapolis, Minnesota, ADC has approximately 8,900 employees around the world and annual sales of $1.5 billion. For additional information, visit the company web site at www.adc.com. MIND CTI Ltd., is a private company registered in Israel with an office in Englewood Cliffs, NJ. Owned by key MIND personnel, founders and ADC Telecommunications Inc., MIND supplies the telecom industry with software for billing and management. MIND's call management and billing products are installed in 20 countries. For more information on MIND and its products, visit the company web site at www.mindcti.com. Contact: Lynne High-Marketing Communications ADC Telecommunications (612) 946-3136 Lynne_High@adc.com Steve Gordon-Marketing Director ADC Telecommunications (410) 872-3749 Steve_Gordon@adc.com Barbara Frank - IP Telephony Billing Marketing Manager MIND CTI (201) 569-6967 or 972-4-993-6632 Barbara@mindcti.com Best regards, Andrea Dray Sales Secretary MIND C.T.I. Ltd. Computer Telephony Software POB 144, Yokneam Illit 20692, ISRAEL Tel: +972-4-993-6688 Fax: +972-4-993-7776 Mail To: sales@mindcti.com Visit our site: http://www.mindcti.com ============================ Keep us in mind! ============================ ------------------------------ End of TELECOM Digest V19 #59 *****************************