From telecom-request@delta.eecs.nwu.edu Tue Sep 12 20:56:15 1995 by 1995 20:56:15 -0400 telecomlist-outbound; Tue, 12 Sep 1995 15:58:13 -0500 1995 15:58:09 -0500 To: telecom@eecs.nwu.edu TELECOM Digest Tue, 12 Sep 95 15:58:00 CDT Volume 15 : Issue 377 Inside This Issue: Editor: Patrick A. Townson FCC Rules Against Carrier Kickbacks to ESPs (Michael D. Sullivan) An Idea for LECs to Communicate Area Code Splits (Richard Layman) # Means #; Number Means a Telephone Number (Mark J. Cuccia) OC-X to Modem at AOL (Stephen Balbach) Re: Variable Length Phone Numbers (Jan Ceuleers) Re: Variable Length Phone Numbers (db@barc.com) Re: Variable Length Phone Numbers (Linc Madison) 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. 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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. ---------------------------------------------------------------------- The FCC staff issued a letter ruling on September 1 that ruled against a variety of techniques used by enhanced service providers to provide "services" such as international dial-a-porn and free BBS/internet access by means of kickbacks to the ESP and/or restricting access to the ESP to a single IXC. Here's the text of the ruling: -----------Text of FCC decision------------ Federal Communications Commission Washington, D.C. 20554 September 1, 1995 DA 95- 1905 Ronald J. Marlowe, Esq. Cohen, Berke, Bernstein, Brodie, Kondell & Laszlo Terremark Centre 19th Floor 2601 South Bayshore Drive Miami, Florida 33133-5460 Dear Mr. Marlowe: This is in response to your informal request for a staff ruling regarding the legality of certain information and/or entertainment programs provided pursuant to tariffed rates for international communications services. Your inquiry is made on behalf of clients who apparently are interested in tariffing "international long distance services" for the transmission of information and/or entertainment programs. You present scenarios whereby calls to foreign destinations providing audio information programs would be transmitted through three different dialing sequences: (1) 10XXX + international number; (2) 1-500-NXX-XXXX; or (3) 1-700-NXX- XXXX. In each case, the calls would be transmitted by an entity authorized to provide international direct dialed telecommunications services pursuant to Section 214 of the Communications Act (the Act) at a tariffed rate. Calls to the international information programs would be billed to telephone subscribers at that tariffed rate as standard toll charges. No charges would be assessed by the information provider directly to the caller or subscriber. You ask whether the legality of the arrangement would be affected if: (1) the carrier remits a portion of the transport charge to the party advertising the destination number; or (2) the carrier remits a portion of the transport charge to the destination entity for providing the information. You also inquire whether the arrangement is lawful if steps are taken so that the destination number could not be accessed through any other carrier, and whether such calls may be billed on a separate page with consumer disclosures as non-deniable (so that disputes do not lead to disconnection of service). As explained below, the staff concludes that it is a violation of federal law for any entity to provide tariffed common carrier communications services in an arrangement -- whether domestic or international -- where charges are assessed for calls to information programs in the manner you describe and/or when the carrier blocks access to a number from other carriers. Common carriers engaged in such practices are not providing common carrier communications services in a just and reasonable manner as required by Section 201(b) of the Act, and are violating both the letter and spirit of Section 228 of the Act. Traditionally, information and entertainment programs have been provided to telephone subscribers at rates exceeding the tariffed transmission rates charged by the transmitting common carrier. Such interstate information services are regulated as "pay-per- call" services under the Telephone Disclosure and Dispute Resolution Act (TDDRA) (codified at Section 228 of the Act) and implementing regulations adopted by both this Commission and the Federal Trade Commission. Our rules require that all pay-per-call services must be provided on the 900 service access code. Common carriers involved in either transmitting and/or billing subscribers for pay-per-call services are subject to several statutory requirements intended to ensure that consumers are able to prevent access to or charges for unwanted information services. Specifically, the TDDRA requires carriers to offer telephone subscribers the option of blocking access to pay-per-call services and prohibits the disconnection of basic telecommunications services for failure to pay pay-per-call charges. While the statute establishes a comprehensive system for federal regulation of pay-per-call services, it specifically exempts from pay-per-call status "any service the charge for which is tariffed" and services offered pursuant to a "presubscription or comparable arrangement." In determining whether an entity licensed as a common carrier may lawfully provide service in the manner you describe, we note first that information programs should not be tariffed as common carrier services. Rather, common carriers may offer information programs only as non-tariffed "enhanced" services in accordance with Section 64.702 of the Commission's rules. Moreover, it is a basic and central principle of common carriage that a carrier may provide tariffed service only as an objective conduit of a customer's communication, without influence or control in determining either the content of the communication or the destination of a customer's calls within its authorized service area. See Amendment of Parts 2, 91, and 99 of the Commission's Rules Insofar as They Relate to the Industrial Radiolocation Service, Report and Order, 5 FCC 2d 197, 202 (1966). Through payments to an information provider or destination entity (other than standard settlement payments), a carrier would abandon objectivity and acquire a direct interest in promoting the delivery of calls to a particular number for the provision of a particular communication. This precept applies regardless of the particular dialing sequence used to place calls. Also, any carrier that is involved, either directly or indirectly, in blocking access to the called number by other carriers or in determining or influencing the content of the communications delivered through its network is not, we believe, offering a common carrier service. We recognize that long distance carriers lawfully assign numbers in limited circumstances and are the sole carrier to transport calls to such numbers. Restricting access to a particular telephone number that has been assigned for access by multiple carriers, however (or creating fictitious numbers), so that calls to that number can be completed only on one carrier's system is anticompetitive and an unjust and unreasonable practice, because that action deprives consumers of their right to use their preferred carrier. A carrier may lawfully provide service to information providers is only if it has absolutely no involvement or interest in the communications made through its network and does not engage in any action to encourage calls to a particular number or limit access to that number to callers using its transmission services. In summary, in the service scenarios you describe the carrier would appear to be providing an enhanced service, not a basic common carrier communications service. Accordingly, imposing tariffed charges for the service would be an unjust and unreasonable practice under Section 201(b) of the Act. This conclusion is reinforced by the implication that your clients apparently plan to deliver calls only to a limited group of people (information providers), rather than making their service available to call any number at competitive rates using standard communications operator and billing procedures. The services you describe are also unlawful under Section 228 of the Act and the Commission's implementing rules. It appears from your description of the proposed services that your clients desire to operate within the "tariffed service" exception to the definition of pay-per-call service, and thus evade the letter and spirit of those provisions and the important consumer safeguards for information services. The Commission is committed to eliminating abusive practices which deprive consumers of their statutory rights concerning such services. Although Congress exempted from the pay-per-call definition services that are provided on a tariffed basis, we do not believe that the service you describe is encompassed within that exception. The fact that the consumer does not directly pay the information provider does not exclude the service from the definition of pay-per-call if the payment is simply paid to the information provider by the carrier and then recovered from the consumer through the transport charge. In this case, the transport tariff is a sham; the consumer has, in fact, paid the carrier for transport and the provider, albeit indirectly, for the information. Section 64.1506 of the Commission's rules requires that such calls be provided only on the 900 service access code. Clearly, Congress did not intend that the carefully crafted provisions of the TDDRA and Section 228 of the Act could be evaded by the arrangement you describe. The payment of commissions in this instance is not comparable to carriers' payments to aggregators such as pay telephone owners. Those commissions simply compensate aggregators for their costs of making services and facilities available to the transient public for its communications need. See AT&T's Private Payphone Compensation Plan, 3 FCC Rcd 5834, 5836 (Com. Car. Bur. 1988), recon. and review denied, 7 FCC Rcd 7135 (1992). The Commission has found that such commissions are a legitimate business practice so long as callers are not prevented from using any other carrier to place a call. Id., National Telephone Services, Inc., 8 FCC Rcd 654, 655 (Com. Car. Bur 1993). In contrast, the proposed payments to information providers are expressly designed to evade the consumer safeguards set forth in the TDDRA and the Commission's rules. Finally, we note that carriers are issued certificates of authorization under Section 214 of the Act when the Commission determines that such issuance serves the public interest and convenience. We believe that the inherently evasive and anti-consumer and anti-competitive actions that you describe are contrary to the Section 214 mandate applicable to carriers providing international service even absent specific violations of the Act and the Commission's rules. For example, assigning a 500 number to an information provider for termination in a country where the terminating carrier pays the provider to route calls to that location would be, in the staff's view, inconsistent with the public interest mandate in Section 214. Thus, entities who have applied for or hold such authorizations may place such applications or authorizations in jeopardy if they conduct such activities. Because the staff believes that the calling arrangements you describe would violate Sections 201(b) and 228 of the Act, and would be inconsistent with the public interest considerations set forth in Section 214 of the Act, we need not address the manner in which the calls may be billed. Carriers may not bill subscribers for unlawful calls. This is a staff ruling issued pursuant to Section 0.291 of the Commission's rules, 47 C.F.R. 0.291. Applications for review must be filed within 30 days of public notice of this action. See 47 C.F.R. 1.115. Sincerely, /s/ John B. Muleta Chief, Enforcement Division Common Carrier Bureau -----------End of FCC decision------------ Michael D. Sullivan | INTERNET E-MAIL TO: mds@access.digex.net Bethesda, Md., USA | also avogadro@well.com, 74160.1134@compuserve.com [TELECOM Digest Editor's Note: Very interesting, indeed! Does this mean that those services operating under what has been called 'The Nevada Plan' are now illegal? Is it now the case that all those dial-porns operating out of Netherland Antilles, Guyana and elsewhere are going to have to make it on thier own without their kickbacks from AT&T and the other carriers? Are we now to assume that direct delivery of long distance traffic direct from a carrier to a subscriber via T-1 -- eliminating the possibility of non-subscribers (to that carrier) from reaching the called party -- are now illegal? Now, what will happen if a subscriber changes his legal status from that of 'subscriber' to that of 'telco'? By that I mean the telcos have always exchanged traffic among themselves and compensated each other for traffic carried through the others' facilities, etc. Suppose instead of being just an end-subscriber accepting traffic who is no longer able to receive commissions from an LD carrier I become a telco and expect to be paid for the traffic the LD carrier delivers to me for processing? Suppose at my telco, my two (and only two) 'subscribers', i.e. the two women who work the phone room are only allowed to make outgoing calls on a collect basis, and I, as telco, file a tariff charging thirty dollars per minute. My subscribers return calls to their clients -- on a collect basis of course -- and I submit my billing tapes in the usual way. For example, heretofore, I 'reached out and touch a new friend' on a conference bridge operating in Nevada expecting only to pay toll with no additional charge. The carrier took care of compensating the bridge tender with a kickback from toll -- now deemed illegal. Suppose now I take your call of one minute or less duration and I advise you that 'your call will be returned in one minute or less, on a collect basis, using the services of the Bridge Telephone Company. All you need to do is accept our collect call when your phone rings.' Now the bridge tender uses the telephone company which he owns to place calls to customers on a collect basis at the rate he establishes. Presumably that will be legal, where the (in my opinion) more straightforward kickback from toll paid by the carrier is not? Can it be then, that the clients of Integratel who do in fact go through the formalities of actually calling back collect (as opposed to simply converting the billing method in mid-stream) are operating legally? PAT] ------------------------------ Toby Nixon's post about the upcoming split of the 305 area code, made me remember an idea I've thought about that LECs could use to communicate area code splits nationally. Phone companies like NYNEX and Bell Atlantic, and presumably all the others spend a lot of money communicating area code splits within their regions, such as ads in the local newspapers which detailing the changes in exchanges, and at least with Bell Atlantic, putting (I seem to remember) printing on the back of the phone bill envelope listing the exchanges that were now part of the new area code. Why don't the LECs work together to use the billing envelope to communicate area code splits nationwide? Sure that might not get to everyone who needs to know in a business, but it would get the word out to most every household in the U.S., for probably not that much money when you think about. For example, the September phone bill envelope I get from Bell Atlantic could break out the 305/954 split, and list the exchanges that are now going to be in 954. BellSouth could do the same for the 703/540 split in Virginia, etc. I could then check my databases, address books, etc. Although printing a special insert would be expensive, and unfortunately, probably ignored by many, I don't think people would ignore the actual envelope, and the printing on it. Similarly, there could be a statement on all the envelopes about the new types of area codes like "334" and why organizations need to take steps to deal with the implications to their calling systems. Then there might be fewer problems down the line. Although I guess with Ft. Lauderdale getting one of those kind of area codes, most businesses won't let it slide anymore -- cf "I don't call Alabama anyway, why change our phone system now?" úÿ Just a thought that BELLCORE ought to look into. Richard Layman, Mgr., Business Development, and Research Producer Computer Television Network, 825 6th St. NE, Washington, DC 20002 (202)544-5722 - (202)543-6730 (fax) - rlayman@capaccess.org http://www.phoenix.net/~ctn (... I know, it needs work) ------------------------------ With the recent thread of the '#' button's name, I have a gripe about some people who post to TELECOM Digest and use phrases such as 'Calling an 800#'. PLEASE, please when wanting to abbreviate the phrase 'Telephone Number' or 'Number' or NXX-XXXX or 'seven digits', PLEASE don't use '#'. The '#' is *also* a SPECIFIC touchtone button which has special purposes in numbering/addressing or telco functions (as well as private voicemail, auto attendant, etc). For telco, '#' will time out a central office register when dialing *variable-length* strings, such as NX-# instead of NX and waiting -- in some Custom Calling applications -- # will indicate 'end-of-dialing' on international strings. There is also 10-XXX-# 'cut-thru' dialing, and one can get their Operator without having to wait for a time-out with 0-# (LEC) and 10-XXX-0-# (IXC indicated by 10XXX). 0-# does NOT indicate zero plus the number- It means ZERO-POUND (or whatever you call the '#' button). '#' as a first entry key has been proposed (by Bellcore) for 'Facility Codes' of the form #-XX. The 'XX' indicates a type of circuit or transmission facility request, such as broadband, video, etc. #-56 is proposed for requesting a 56 kbps circuit. Note that the other #-XX codes aren't really assigned (yet) and there might possibly be no standardization of their assignments/uses. I don't know what equipment or codes ISDN users go by, but ISDN might just obsolete any plans for #-XX facility codes, however. For Historical Interest: Back in the later 1960's (and early 70's), when AT&T/Bell-System was planning on a future Picturephone service (the CRT type with Co-ax loops/trunks), they planned on an initial '#' button to request a call with the video loop as well as the regular audio telephone loop. One would have called another picturephone as #-(1)-NPA-NNX-XXXX, local picturephone calls as #-NNX-XXXX, and a Picturephone Assistance Operator as #-0-(#). Service calls to Picturephone Information or Picturephone Repair would have been dialed #-N11. Calls to regular voice, non-video numbers, operators and services would continue to have been dialed as normal, without the initial #. (The initial '#' would also control AMA billing, as use of the video loop was charged more than just the audio). When abbreviating, lets try to say something like 0+num. or 0+nmbr. or 0+A/C+num. for 0-NXX-NXX-XXXX (etc). Just my 2-cents for the day, Pat. MARK J. CUCCIA PHONE/WRITE/WIRE: HOME: (USA) Tel: CHestnut 1- 2497 WORK: mcuccia@law.tulane.edu |4710 Wright Road| (+1-504-241- 2497) Tel:UNiversity 5-5954(+1-504-865-5954)|New Orleans 28 |fwds on no-answr to Fax:UNiversity 5-5917(+1-504-865- 5917)|Louisiana(70128)|cellular/voicemail [TELECOM Digest Editor's Note: I use my heavy-handed editor's red pencil to change that notation when it appears here. I get a lot of messages where people write something like "I tried to call that #" ... and I *always* change '#' to the word 'number' before releasing the article. Speaking both of Picturephone and 'adult' information providers in the same issue as we are this time, I am reminded of the fellow down in south Florida who experimented with this for a few years in the 1980's. This guy was an oldtime 'swinger magazine' publisher -- a 'paper dealer' as we used to call them. You submitted ads and photos to his little magazine and he ran them along with others. Then of course he made a commission as the reader/writers exchanged personal correspondence based on the ads in the magazine, all of which had to be forward through his remail service, at least the first time. If a 'woman' (hint, hint! like the games they play on Compuserve CB at night) submitted her picture and message to the magazine, she could be assured of getting *TONS* of mail in her post office box a couple months later from men all over the USA with various lewd photos and letters in re- turn. This guy made his money from all the ten dollar fees to run your picture and message in the magazine along with the one dollar bills received to forward your response to the advertiser. He got paid from both directions. He decided one day to get into picturephone one day with live people at his end who would chat and display themselves to callers. He bought up a huge surplus of the 'slow scan' type picture phones; the ones that only change their image every ten or fifteen seconds. He offered these on a purchase or lease basis to the subscribers of his magazine or said they could purchase their own from whatever source, and of course with billing approved by your credit card company, you could call in to chat with (and view) other members of his club ... I don't know whatever came of it or how successful it was, but it occurs to me if some of the present- day adult information providers got into picturephone there could be a lot of money in it. Do you remember how, many years ago -- nah, you are all too young to remember -- when tape players and cassette players were very new, how the Columbia Record Club offered to send you a portable tape cassette player -- for free, mind you! -- if you promised to join the Club and purchase some minimum number of tapes each year? More people got their first tape cassette player (this was back in the era when we were seeing a conversion from the old 'wire recorders' to magnetic tape recorders, in the early 1950's) as a free gift from the Columbia Record Club (later renamed the Columbia Record and Tape Club; nowdays Columbia House or perhaps CBS Products, but still in Terre Haute, Indiana) by sending in those coupons found in magazines and the Sunday papers .... Battery operated tape players were the rage when I was in high school; little pieces of magnetic tape in a case that would unwind onto another spool and play the music therein ... more people became aware of that 'new technology' in the fifties because of taking the bait and signing up with Columbia Record Club ... and please check the box if you want classical, country and western, or whatever. I think you had to promise to buy one tape each month for two years from the 'club magazine' sent to you in the mail each month. If you did not return the card they sent then you got the tape they selected and got billed for it anyway. Now it occurs to me that if the telcos would really like to see picture phone take off in a big way, they should cut a deal with the adult IPs in a similar way. The IP could start a club and offer to supply picture phones to new club members either free or at a greatly reduced price in exchange for the new club member's promise to use the IP's services on some regular basis. "Phone our service and chat with us at least once each week for a year and we will send you at no charge a picturephone to use when you call, because the young ladies and gentlemen here want to be able to show you what they are doing as they chat with you about it." Probably they would bill your credit card for a few hundred dollars and send you the picturephone, then give you credit toward a certain number of minutes/hours of service with them in the process. The IP's would cut a deal with telco to get the units as cheap as possible, in the same way Columbia Record Club cut a deal with (I think it was) the old Zenith people to get those portable radios with the tape players built in. The obvious drawbacks: the IPs would need to have legitimate people there, and not the nasty ones (in real life) they use now. grin. PAT] ------------------------------ I was speaking with someone who was speaking with a Bell Atlantic technician who does some of the work for AOL in Virginia. Was curious how they bring in thier modem traffic and it is by OC-X (where X is some number Im not sure). There has been a lot of talk about terminating modems using T1's, but what equipment is there to terminate at the T3 or OC level? Thats a lot of POTS lines. Stephen Balbach "Driving the Internet to Work" VP, ClarkNet due to the high volume of mail I receive please quote info@clark.net the full original message in your reply. ------------------------------ In article 6@eecs.nwu.edu, naddy@mips.pfalz.de (Christian Weisgerber) writes: > First, let me state that I see *no reason whatsoever* why there can't be > variable length phone numbers or why a switch would have to know the > total length of the number. If you think there is a need for such > restrictions, please explain why you think so. Your reasons are not > obvious. In situations where compelled signalling is used on one stretch of the network, and non-compelled on the next, the switch that implements this tandem function needs to know the exact number of digits or implement a timeout (and leave the principle of compelled signalling). Let me give you a specific example. A large Belgian organisation has its own private network, which it uses for least-cost routing. This private network uses R2 signalling (compelled). The PBX that routes calls it receives from the private network back onto the public network needs to know how many digits to expect, so that it knows when to send the backward A-6 signal to indicate end-of-dialing instead of the A-1 signal that asks for the next digit. This is needed both in case the PBX is connected to the public network by means of analogue trunks, and in the ISDN T0/T2 case where en-block sending is used. If this PBX does not know the number of digits to expect, it must always send the A-1 signal anyway, and send a pulsed A-6 signal if no additional digit has been received within a timeout (see Q.442). This is however an ugly kludge that can cause problems, both in the signalling and in the ergonomy of the user. We luckily don't have to struggle with this problem, since the Belgian numbering plan is closed. However, if the private network is ever going to be used for international least-cost dialing, we'll have a problem ... > I would also like to point out that in Germany, where I live, telephone > numbers vary in length, in fact my voice number is +49.621.5870460 and > my modem number is +49.621.583214, area codes vary in length (2..5 > digits), we have DID numbers of different lengths, and all of this > without any kludges like second dial tones, timeouts, etc. Claiming that > this is impossible is ridiculous in face of the facts. You are quite right that this works fine if the signalling system is compelled end-to-end. Jan Ceuleers Alcatel Bell Telephone hw/sw devt. engineer Business Systems & Networks Division vox +32-3-450-3145 fax +32-3-450-3579 ceuleerj@bsg.bel.alcatel.be #include "std/disclaimer.h" ------------------------------ In , naddy@mips.pfalz.de (Christian Weisgerber) writes: Ok ... I didn't see the original posting, and am completely the layman here, but some things come to mind. (If I'm wrong, someone will correct me ... and I'll definitely learn something ... the reason I'm here in the first place :)) > First, let me state that I see *no reason whatsoever* why there can't be > variable length phone numbers or why a switch would have to know the > total length of the number. If you think there is a need for such > restrictions, please explain why you think so. Your reasons are not > obvious. ..stuff deleted... > What must a switch do during call set-up? It receives dialing > information (single or multiple digits) from an inbound trunk (or from > the line card, if it is the caller's switch), and, after collecting > enough of these, selects an outbound trunk. Further dialing info it > receives is passed on to the switch on the outbound trunk. Note that > no trunk line has to be actually connected yet. The destination switch > collects dialing info until a line that it serves is identified, then > it initiates a ring signal. Information about this is passed back the > chain of switches to the caller's switch which locally feeds a "remote > is ringing" signal. When the called line answers, again information is > passed back to the caller's switch, and now the speech circuit is > actually activated along the switch chain. Is this truely how it works? I can understand the written logic of it, but see problems is several areas (1) dymanic routing of calls (2) the anticipated 'number transportability' (3) routed calls like 800- 500-, etc. It seems like in the above situation, the full number would be required -up front-, or, as you mentioned, there would need to be some time-out mechanism or 'end key' (like a #, *, etc), to signify termination of the sequence. Then again, I could easily be all wet. If all numbers are available from the start, it seems like the routing sequence would have less traffic than if there were a continual transmission of the 'next' number involved in the dialing sequence. It seems to make sense logically. But it also seems to make sense that, at least currently, all numbers are required before the sequence starts or wouldn't things like trunk busy signals, the recordings about 'all circuits are busy' etc., come before we finished dialing all the numbers? instead of waiting until all digits are dialed first? (I remember some cities didn't require '1' before dialing long distance, but I believe that's no longer true, so that one is moot.) > It also worked with the prior German > phone technology, purely electro-mechanical switches. (That's relays, > levers, etc. No transistorized technology whatsoever.) With that > technology speech circuits were connected through to the next switch > already during dialing, though. Coming from the old crossbar, strowger switches as a kid, that seems easier. But even then, number lengths were fixed locally in my hometown. Five digit numbers were private lines or pbx's, six were always party lines (same as five digits, and last was used to differentiate the frequency of the ringing current to ring the correct party). ------------------------------ Christian Weisgerber (naddy@mips.pfalz.de) wrote: > Many posters, especially those from North > America, insist on their belief that phone numbers have to be of > constant length, otherwise one must have timeouts etc. > First, let me state that I see *no reason whatsoever* why there can't be > variable length phone numbers or why a switch would have to know the > total length of the number. If you think there is a need for such > restrictions, please explain why you think so. Your reasons are not > obvious. Within the North American phone system, telephone numbers must be of an easily predictable length. That is because much of the hardware in our switching system is designed with the requirement that the originating switch know when the subscriber has finished dialing, without inquiring of the terminating switch. Here is a sketch of what happens in North America when you dial. The letter N represents a digit other than 0 or 1. 011 - international call, expect minimum 7, maximum 12 digits to follow. Dialing must conclude with time-out or # key 01N - international call, but operator assisted; as above 00 - long distance operator; no further digits permitted 0 - local operator; dialing requires time-out or # key 11 - special service code -- exactly two digits follow, then restart dialing sequence. 10 - carrier selection code -- exactly 3 digits follow, then restart dialing sequence [this does not account for 101XXXX codes] 0N - operator-assisted call, expect 0-NXX-NXX-XXXX 1N - direct-dialed call, expect 1-NXX-NXX-XXXX N - examine first three digits for special cases (911, 411, etc., and in some areas an area code in the local area; in each of those cases, the number of digits to be expected is determined from the first three numbers dialed); otherwise, local number: NXX-XXXX The only cases I know of where the total number of digits expected cannot be determined from the first three digits dialed are international calls (length varies) and in some areas the special case 141, which may be 1+411 or 1+41X-NXX-XXXX. (In Southwestern Bell territory, you dial 1+411 because there is a charge for the call.) In any case, with the exception of international calls, the number of digits expected is known within the first four digits of dialing. The advantage of this scheme is that the originating switch does not need to open a path all the way to the terminating switch until dialing has been completed. The originating switch stores the entire number and then opens a path and sends it along its way, or may open a path part way through the dialing process and pass the initial digits and then pass the remaining digits in real time. In either case, it knows when dialing is complete and can take the dialing register off that line. Other countries have systems that use variable-length numbers without requiring time-outs, because they open the path as the subscriber dials and the terminating switch returns an indication that dialing has been completed. So, in sum, variable-length numbers work fine in systems designed for variable-length numbers. They work terribly in systems designed for fixed-length numbers. In order to use variable-length numbers in the North American system, we would have to replace large segments of our switching system. We could implement a scheme that said, for example: 1212, 1213, 1214, 1312, 1314, 1305, 1713 -- eight digits follow all other 1-NPA combinations -- seven digits follow and program each local switch to know whether local numbers are seven or eight digits. This would allow each area code to have EITHER seven-digit or eight-digit local numbers, but not both. That would require analyzing at least five digits to determine expected length. The other problem with this scheme is that permissive dialing would be essentially impossible: all numbers would have to be splash-cut at once in the affected cities. The other minor impediment is that not only every local C.O. switch would have to be reprogrammed, but also every single PBX in North America. Given that we've seen how well PBX managers bury their heads in the sand when faced with something as simple as NXX prefixes and NNX area codes, expecting them to cope with eight-digit numbers in some area codes would be a bit of a reach. Linc Madison * San Francisco, California * LincMad@Netcom.com ------------------------------ End of TELECOM Digest V15 #377 ******************************