30 Years of the Digest ... founded August 21, 1981
The Telecom Digest for December 1, 2011
====== 30 years of TELECOM Digest -- Founded August 21, 1981 ======
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Date: Mon, 28 Nov 2011 19:30:32 -0500 From: "Geoffrey Welsh" <firstname.lastname@example.org> To: email@example.com. Subject: Re: Cell phones: more texting, less talking? Message-ID: <d9a88$4ed42788$cf707dba$25218@PRIMUS.CA> HAncock4 wrote: > Has text message traffic overcame voice message traffic? Could > someone expand on today's cell phone traffic mix? Thanks. A quick Google tells me that a GSM 'half-rate' codec requires 6.5 kbit/sec; a 140 character message is 1120 bits of payload and the average text length is probably much less than 140 characters so it would take several texts per second - which is how many texting users? - to equal the bandwidth consumption of a single voice call. So I'm betting that voice still accounts for the vast majority of the bits moved by the mobile carriers. If someone actually has figures I'd be interested to know if I just cemented my position as the anti-analyst of telecom economics. <grin>
Date: Mon, 28 Nov 2011 18:57:33 -0800 (PST) From: Joseph Singer <firstname.lastname@example.org> To: email@example.com. Subject: Re: Update on at&t/T-mobile merger Message-ID: <1322535453.92648.YahooMailClassic@web161508.mail.bf1.yahoo.com> Thu, 24 Nov 2011 20:55:08 -0800 (PST)HAncock 4 wrote: > To me it seems if the whole point of the Bell System Divesture was > that public interest required smaller competing companies, then this > merger should not be allowed. Aren't both wireless companies big > enough on their own to compete successfully? One of the points of this acquisition is that T-Mobile is a distant fourth place in the US mobile market. If it were not for the fact that Sprint bought Nextel they'd be about the same size as T-Mobile is right now. T-Mobile has several things going against it. T-Mobile has always been relegated to using the PCS (1900 Mhz) frequency as opposed to Verizon and AT&T being the remnant of the original A and B cellular carriers using the 850 frequency which propagates a lot better over long distances and also penetrates structures better than does PCS. Sprint also has a surfeit of spectrum which is why most all the CDMA MVNOs use Sprint since they can sell their excess spectrum to the MVNOs. T-Mobile does not have a whole lot of PCS spectrum. Several years ago they won the wireless auction for "AWS" (Advanced Wireless Services) spectrum in the 1700 Mhz range. This is an "oddball" bit of spectrum and unless equipment manufacturers specially design for this range they are limited to what they can offer customers to use. This is likely why of all the major US carriers T-Mobile is the only one that did not get the iPhone since Apple would have had to engineer yet another frequency set into the iPhone. And since 1700 Mhz is really only used by a few carriers it wasn't really worth it for Apple to design it into the iPhone.
Date: Tue, 29 Nov 2011 10:02:03 -0800 (PST) From: Joseph Singer <firstname.lastname@example.org> To: email@example.com. Subject: Re: MSNBC/NYT: Caller ID Forging Message-ID: <1322589723.34385.YahooMailClassic@web161501.mail.bf1.yahoo.com> Sun, 27 Nov 2011 15:23:34 -0500 "r.e.d." wrote: > Can someone point to technical articles/references/etc. giving > details about how various methods of caller-id spoofing work? Down > to the level of bits in signaling protocols, trunk interfaces, etc. Basically as I understand it and from doing a limited google search it involves using a PRI "Primary Rate Interface" line and manipulating the outbound caller ID which you can do with that type of service. I found this reference which explains it pretty well: http://www.calleridspoofing.info/
Date: Mon, 28 Nov 2011 19:09:48 -0800 (PST) From: Joseph Singer <firstname.lastname@example.org> To: email@example.com. Subject: Re: Cell phones: more texting, less talking? Message-ID: <1322536188.39905.YahooMailClassic@web161506.mail.bf1.yahoo.com> Sun, 27 Nov 2011 09:21:39 -0800 (PST)(HAncock4) wrote: [little snippo] > Anyway, I did notice a number of passengers 'thumbing away', that is, > apparently sending and receiving text messages. > I understand text message traffic has gone up, which the cell carriers > love because texting uses less bandwidth capacity than a voice call > does, but they charge more for it. One needs to pay extra to get > unlimited texting. Otherwise, as many parents found out the hard way, > texting is expensive. > Has text message traffic overcame voice message traffic? Could > someone expand on today's cell phone traffic mix? In the last few years there's been a switch in the way some people communicate. Generally younger users now prefer to use text messages to communicate rather than making a voice call. Some hardly use voice calling at all and communicate via text message or using one of the social networks such as Twitter or facebook. It's as if voice calling is not used for the most part. This behaviour is more pronounced with younger users. Older users still prefer to make a voice call. >From September, 2008: "The average U.S. mobile phone subscriber now sends and receives more text messages than voice calls, finds Nielsen Mobile in recent research, with a typical U.S. teen sending and receiving over 1,700 text messages every month." http://www.bizreport.com/2008/09/nielsen_mobile_texting_vs_talking.html
Date: Tue, 29 Nov 2011 07:03:54 -0800 (PST) From: Wes Leatherock <firstname.lastname@example.org> To: email@example.com. Subject: Re: Re.: Cell phones: more texting, less talking? Message-ID: <1322579034.88417.YahooMailClassic@web111723.mail.gq1.yahoo.com> --- On Mon, 11/28/11, John Stahl <firstname.lastname@example.org> wrote: > Isn't it amazing how human beings (is it at a certain age level - or > should I ask is it "up to" a certain age level) have become so > non-verbal in their inter-personal communications? I would suggest you may mean non-oral. Texting is certainly verbal (meaning to use words or representations of words). This is a very common misuse of verbal to mean spoken. Wes Leatherock email@example.com firstname.lastname@example.org ***** Moderator's Note ***** Learn something new every day. Bill Horne Moderator
Date: Mon, 28 Nov 2011 21:23:36 -0600 From: email@example.com (Gordon Burditt) To: firstname.lastname@example.org. Subject: Re: MSNBC/NYT: Caller ID Forging Message-ID: <mKGdnc--huilzUnTnZ2dnUVZ_rydnZ2d@posted.internetamerica> > Can someone point to technical articles/references/etc. giving details about > how various methods of caller-id spoofing work? Down to the level of bits > in signaling protocols, trunk interfaces, etc. I believe there are several ways to get spoofed caller-id. One is exploiting the cheap caller-id devices people have on their landline phones. The caller-id info is transmitted by a modem-like signal between the first and second rings on landlines. However, the stupid caller-id device keeps listening, and sending a fake signal after the voice channel opens can scroll the real number off the caller-id and can inject a fake one. I'm not so sure this works against cell phones, PBX's, etc. where the method of receiving caller-id is different. A modern PBX with hundreds of lines is able to pass off the caller-id info to make it useful - it's a feature - sending out the one public "operator" number for the whole company is not really useful, and some companies actually want you to be able to call back the particular person who called you. However, passing the caller-id info opens up the opportunity to fake it. I suppose that the phone company could check that the number coming from the PBX is one assigned to them, but that is often too much trouble, and an issue with multiple providers (what if the company wants their caller-id to be their 800 number, which is provided by a different company, and forwarded to one of their incoming trunks?). VOIP systems pass the number as part of the protocol. It's particularly easy with providerless VOIP to call someone's gateway for 800 numbers from a phone that doesn't even have an incoming phone number. Some of those gateways do minimal validation - they won't accept a call with no caller-id, and I think it refused to accept 1-111-111-1111, but it pretty much has to accept whatever valid phone number you pass. It's really easy to fake caller-id if you are interfaced to the phone system as a phone company - especially one in a foreign country. > To allay concerns, I want to understand this better to try to figure out > ways to alleviate the problem. I'm an ex-big-telecom systems engineer (Bell > Labs, etc.) who was in the business when Local Area Signaling Services (SS7 > for local switches) was introduced, making Caller-ID possible, and it's > irritating to me that a service intended to eliminate heavy breathers is now > being subverted. To some extent, I appreciate the faking, if they use a consistent fake number, like 1-111-111-1111, I'll have no hesitation against blocking it, as it can't be a real number. (Smartphone apps ought to be able to block any one of several million numbers without any problem.)
Date: Tue, 29 Nov 2011 11:17:55 -0500 From: Pete Cresswell <email@example.com> To: firstname.lastname@example.org. Subject: Re: Telemarketing On Your Cell Phone? Message-ID: <email@example.com> Per Monty Solomon: >Telemarketing On Your Cell Phone? > >Congress may soon open up your cell phone to robocalls. Will this put >a telemarketing hell in your pocket? Gotta wonder why the authors do not identify the sponsors/co-sponsors of that bill ("H.R. 3035: Mobile Informational Call Act of 2011"): Rep. Lee Terry [R-NE2] Marsha Blackburn [R-TN7] John Gingrey [R-GA11] Leonard Lance [R-NJ7] Blaine Luetkemeyer [R-MO9] David McKinley [R-WV1] Mick Mulvaney [R-SC5] Pete Olson [R-TX22] Michael Rogers [R-MI8] Edolphus Towns [D-NY10] per (http://www.govtrack.us/congress/bill.xpd?bill=h112-3035) Seems to me like it's right up there with pizza being qualified as a serving of vegetables in school lunch programs as an example of "The Best Government Money Can Buy". -- PeteCresswell ***** Moderator's Note ***** If we had the best government money can buy, I'd ask for a refund. What we have is the best government someone else's money bought, and they have more money that I do. Bill Horne Moderator
Date: Tue, 29 Nov 2011 16:30:07 +0000 (UTC) From: "Adam H. Kerman" <firstname.lastname@example.org> To: email@example.com. Subject: Re: Update on at&t/T-mobile merger Message-ID: <firstname.lastname@example.org> r.e.d. <email@example.com> wrote: >I'm not sure your characterization of the point of the breakup [of AT&T] >is completely correct. My understanding is that the issue was not size, >but that fact that AT&T owned not only long distance and equipment >manuracturing. but local service. Creative accounting could cause the >regulated local services to subsidize the other parts of the business, >particularly long distance, at the expense of local rate-payers, so fair >competition for long distance services would not be possible as long as >it remained one company. Is there a significant amount of support that there was a cross subsidy between fees paid by local rate payers benefiting long distance rate payers? I thought the fairness issue, still not resolved today, was what contribution long distance should make to the cost of the calling party and the called party's switches and if local calling rates on either end should be charged in addition to the long distance charge. The cost of operating Long Lines themselves probably weren't charged to any local ratepayers.
Date: Tue, 29 Nov 2011 23:27:18 -0600 From: firstname.lastname@example.org (Robert Bonomi) To: email@example.com. Subject: Re: MSNBC/NYT: Caller ID Forging Message-ID: <juSdnaavHv4rI0jTnZ2dnUVZ_rOdnZ2d@posted.nuvoxcommunications> In article <bMCdnfytL_HnAU_TnZ2dnUVZ_gidnZ2d@earthlink.com>, r.e.d. <firstname.lastname@example.org> wrote: > >To allay concerns, I want to understand this better to try to figure out >ways to alleviate the problem. I'm an ex-big-telecom systems engineer (Bell >Labs, etc.) who was in the business when Local Area Signaling Services (SS7 >for local switches) was introduced, making Caller-ID possible, and it's >irritating to me that a service intended to eliminate heavy breathers is now >being subverted. > Without going into detail, anyone who controls an SS7 node can cause any line to generate arbitrary CID information for any outgoing call. If the 'telephone company' is a 'bad actor', ANY call information can be forged/ corrupted/incorrect/inaccurate/untrustworthy. The PSTN is much like the early Internet in this respect -- every node 'trusts' every other node to be 'honest' about what they're doing. And there are little-to-no provisions for either 'detecting' OR 'rejecting' dishonest actions. That said, the 'alternative' -- having every node 'know' what CID info was allowable from every neighbor node -- is impractical to implement. Secondly, CPE with 'digital' interconnect (ISDN PRI or better) to the LEC have the ability to supply the CID data for every outgoing call. The LEC -can- apply 'filters' to this customer-originated data -- and only 'pass' data that is within a block assigned to that customer. SOME providers -do- do this. MANY do not. The 'simple' description of "how it's done" is that the gear that -generates- the CID data is under the control of the party making the call, and can be 'coerced' to do 'what the caller wants', regardless of what is 'correct'. An 'immediate upstream' telephone company -- an LEC or IXC -- could check, and limit the data the customer puts in those fields. BUT, doing that 'costs money' -- for the database, for the software that makes the check for -every- outgoing call, for the labor of putting info in the database, and for the labor of verifying that the customer is 'entitled' to use those numbers. And all that 'cost' does NOTHING to benefit the phone company, or the customer who is making the outgoing calls. Which leaves the question hanging: "WHY -should- the phone company spend all that money for 'no return'?" If they have the legal option of not doing it, why reduce profitability by doing it? Viewed in -that- light, doing the filtering is a 'breach of fiduciary responsibility' to their stockholders. The ONLY way the matter is going to be resolved in favor of customers is by governmental regulation. Aggressively enforced regulation specifying two things, with stiff penalties for any violations: 1) that end users can only supply CID info that identifies -them- as the calling party. e.g. OK to use their toll-free number, or the number of their switchboard, but not a number that belongs to 'somebody else', or one that is 'not currently issued'. 2) That a telephone company must 'verify' customer-provided CID info on every call, and restrict the number presented to numbers that are 'confirmed' as belonging to the calling party. There are two areas of 'difficulty' with this -- trans-border calls, and domestic VoIP gateways. Disallowing 'domestic' numbers as CID on transborder calls would be one way of dealing with the first issue. VoIP is 'solvable' by aggressive checking/tracking of 2) above, with forcible termination of PSTN connectivity for those with sub-par compliance.
Date: Tue, 29 Nov 2011 16:07:58 +1100 From: David Clayton <email@example.com> To: firstname.lastname@example.org. Subject: Red hot, smoking iPhone self-combusts on airliner Message-ID: <email@example.com> Pics in the URL. http://www.theage.com.au/digital-life/mobiles/red-hot-smoking-iphone-selfcombusts-on-airliner-20111129-1o3zn.html Red hot, smoking iPhone self-combusts on airliner November 29, 2011 - 1:03PM Ben Grubb An Apple iPhone 4 was glowing red hot and emitted a "significant amount" of dense smoke as it spontaneously combusted on board a flight in Australia in the second reported incident of its kind in the past month. It's not the first time electronic devices have exploded or caught fire. Numerous incidents have occurred over the past decade including Dell laptops catching fire, a journalist's LG phone catching fire and Sony Australia recalling 4300 laptops (440,000 globally) from its Vaio TZ series due to fears they could overheat, damaging the machines and potentially burning users. In 2009 iPhone users in France also reported similar incidents. The incident involving a passenger's iPhone 4 glowing red hot occurred on board Regional Express flight ZL319 operating from Lismore to Sydney last Friday after landing, the airline reported. The second incident, which Fairfax Media was made aware of by an anonymous reader, allegedly happened on November 3 when their iPhone 3GS (an earlier model) did something similar. The reader provided pictures as evidence. In an emailed statement at 12.35pm today, Apple Australia spokeswoman Fiona Martin said the company was looking "forward to working with officials" investigating the first incident. No comment was offered on the second incident. In a statement regarding the first incident, Regional Express said a flight attendant carried out "recovery actions" immediately and that the red glow was extinguished successfully, adding that the matter has been reported to the Australian Transport Safety Bureau (ATSB) as well as the Civil Aviation Safety Authority (CASA) for investigation and directions. All passengers and crew on board were unharmed, the airline said. CASA spokesman Peter Gibson told Fairfax today that the ATSB was going to strip the iPhone 4 down "and try and understand what happened". The intention was "to do that some time this week", he said, adding that the iPhone 4 was no longer operational. Anecdotally he had never heard of a similar incident occurring during or after a flight. An ATSB spokeswoman said it was very early in their investigation "for anything to happen in regards to the investigation". Its website lists the incident as involving fumes, smoke and fire. The second incident involved an iPhone 3G model's battery allegedly exploding after a software upgrade. "My iPhone was expanding in size in terms of its width," the anonymous reader said. "[It] continued to grow in size. Before long the phone refused to even turn on and ... just expanded to what it looks like now." The reader noted that - like others - their battery life "was rapidly shrinking after updating to the iOS5 .... so much so that it would go completely flat once I got to 30 per cent". Apple acknowledged battery life issues remained after another update. The reader suspected there was a clear link between their upgrade to the iOS5 software and their battery "exploding". They said that what was "even worse" was the fact that Apple requested $89 for their iPhone 3GS to be fixed. "I'm the person who lost all their contacts, all my saved university files, all my photos - and now I'm the one whose being asked to fork out the dollars to get it fixed. Are you kidding me?"
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