29 Years of the Digest ... founded August 21, 1981
The Telecom Digest for July 04, 2011
====== 29 years of TELECOM Digest -- Founded August 21, 1981 ======
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Date: Sat, 2 Jul 2011 16:52:55 -0400 From: Monty Solomon <firstname.lastname@example.org> To: email@example.com. Subject: Staples resold devices holding consumer data Message-ID: <firstname.lastname@example.org> Staples resold devices holding consumer data Canada audit rips Mass.-based chain By Jenn Abelson Globe Staff / June 22, 2011 Staples Inc. has repeatedly put consumers' data at risk in Canada by failing to wipe clean returned storage devices that contain sensitive information and are then resold. Those findings were reported yesterday following an audit by the Office of the Privacy Commissioner of Canada. The audit included tests of storage devices, including computers, USB hard drives, and memory cards that had undergone a "wipe and restore'' process and were destined for resale. Of the 149 devices tested, 54 contained customer data, including "highly sensitive personal information'' such as health card and passport numbers, academic transcripts, banking information, and tax records. "Our findings are particularly disappointing given we had already investigated two complaints against Staples involving returned data storage devices and the company had committed to taking corrective action,'' Canada's privacy commissioner, Jennifer Stoddart, said in a statement. "While Staples did improve procedures and control mechanisms after our investigations, the audit showed those procedures and controls were not consistently applied, nor were they always effective - leaving customers' personal information at serious risk.'' ... http://www.boston.com/business/articles/2011/06/22/staples_resold_devices_holding_consumer_data/
Date: Sat, 2 Jul 2011 19:08:43 -0700 (PDT) From: Lisa or Jeff <email@example.com> To: firstname.lastname@example.org. Subject: Postage stamp honors 302 set Message-ID: <email@example.com> The US Post Office issued stamps honoring various industrial designers. One is Henry Dreyfus, who designed the 302 desk set of 1938. Nice picture of the phone on the stamp. Also honored is the designer of the IBM Selectric typewriter. http://www.philly.com/philly/entertainment/20110701_New_stamps_honor_U_S__industrial_designers.html
Date: Fri, 01 Jul 2011 08:32:45 -0500 From: firstname.lastname@example.org (Robert Bonomi) To: email@example.com. Subject: Re: Trials of 'super WiFi' to begin in Cambridge Message-ID: <6PednSCkfYngUZDTnZ2dnUVZ_vKdnZ2d@posted.nuvoxcommunications> In article <siegman-5AA66D.firstname.lastname@example.org>, AES <email@example.com> wrote: > >If these spectral bands are currently empty of deliberate signals (in >most locations anyway), are they "white space" or "black space"? When you tune to those frequencies, does the receiver pick up 'white noise' or 'black noise'? <*evil grin*>
Date: Fri, 1 Jul 2011 15:39:03 +0000 (UTC) From: "Adam H. Kerman" <firstname.lastname@example.org> To: email@example.com. Subject: Re: Flash Exploits on the Loose: Update Now Message-ID: <firstname.lastname@example.org> John C. Fowler <email@example.com> wrote: >Flash Player likes to check for its own updates, so don't be surprised >if you're already running the current version. On Firefox and similar browsers, that had required installation of the GetPlus+ extension to regularly check for plugin updates. I don't like plugins that install additional unwanted software, so I just check manually every so often. Previous Flash downloads from Adobe's Web site forced you to download the extension and then had the extension download the plugin. I kept removing the extension. If you see the proprietary "download manager" popup, that's from GetPlus+. The plugin won't complete the installation unless you click the "acknowledge and agree" when the license window pops up. Then you have to click the "close the download manager". I don't know how Adobe could have required additional unnecessary steps but it's annoying and it's easy to miss the acknowledgement step when the license agreement window pops up. Internet Explorer doesn't use plugins but ActiveX controls and I never experienced automatic updates for Flash. There may be a GetPlus+ control to implement the automatic update checks, but someone more familiar will have to answer.
Date: Sat, 02 Jul 2011 12:15:42 +1000 From: David Clayton <firstname.lastname@example.org> To: email@example.com. Subject: Re: Battery power support today Message-ID: <firstname.lastname@example.org> On Thu, 30 Jun 2011 18:36:01 -0500, Robert Bonomi wrote: > In article > <siegman-D89C20.email@example.com>, AES > <firstname.lastname@example.org> wrote: ........... >>Do normal telecom or WiFi/WiMax signals in the 1 to 2 Ghz range pose >>threats comparable to a leaky microwave oven. > > A 'standard' microwave oven generates 700-1000 watts of RF. "compact" > microwaves are generally 500 watts, with a few as low as 350 watts. > > WiFi signals are in the tens of _milliwatts_. Call it 1/10,000 to > 1/100,000 of the RF level inside a microwave. > > Microwave oven safety standards limit leakage to 5 milliwatts per cm2 at > 5cm from the outside of the oven. > > RF energy levels diminish as the square of the distance from the > transmitter. > > Assuming a WiFi signal of 50mw (typical units are around 20mw, 'legal > limit' is 100mw), at a distance of 10 cm from the antenna, the energy > density is 0.08mw/cm2. At 2cm from the antenna, RF energy approaches > the allowable leakage (measured at 5cm) from a Microwave oven. > > To put things in perspective, the signal from a WiFi node is about 1/6 > the "allowable" leakage from a microwave oven. Or around 3x the leakage > of a typical microwave oven in 'good working order'. Add in the fact that digital sources like Wi-Fi only transmit when required (or "Polling") so the overall power diminishes with that duty cycle. The biggest concern is that microwave ovens are designed to use a frequency that is most efficient for heating water molecules, and devices that share that spectrum will also have the same effect. Guess what sort of molecule the human body mostly is composed of? -- Regards, David. David Clayton Melbourne, Victoria, Australia. Knowledge is a measure of how many answers you have, intelligence is a measure of how many questions you have.
Date: Sat, 2 Jul 2011 09:40:29 -0700 (PDT) From: Lisa or Jeff <email@example.com> To: firstname.lastname@example.org. Subject: Re: Battery power support today Message-ID: <email@example.com> On Jun 30, 9:53 am, klu...@panix.com (Scott Dorsey) wrote: > Well, the primary argument is, considering that we have had high > power AM broadcast in the US for ninety years now, and a whole lot > of people have worked in very strong RF fields, that if there was > going to be a substantial health risk it would have been noticed > almost a century ago. I'm not sure if that's accurate. Gong back 40 years, let alone 90, we lived in a world where a great many people smoked and were exposed to industrial and automotive pollutants in the air and at the worksite. These all could generate illness in their own right and mask long-term ill effects from things like high power AM transmitters. Things were even worse going further back in time. (IMHO, the above-ground nuclear testing of the 1940s and 1950s didn't help us any, but I don't know if anything, such as increased leukemia rates, have been documented.) In addition, going way back it seems they focused more on acute health effects rather than long term trends. In my readings of WW II radiation safety in the Manhattan Engineer District, they focused on noticeable immediate radiation effects. It should be noted that many personnel would not cooperate with safety officers because it interfered with their work, and they allowed themselves more exposure than permitted. I sense that scientists back then belittled the radiation risk. One woman scientist wrote of taking radiation measurements of a early reactor while pregnant, and she hid her pregnacy so she could still work. I understand there were subsequent long term health studies done of MED workers, but they're extremely technical and hard to interpret. Today, many of those pollutants have been eliminated or sharply reduced in the US. There's a lot less heavy industry and automobiles have stronger pollution controls. On the flip side, we live in a power-hungry world today with heavy use of air conditioning and electronic devices and of course increased population. In addition, electricity is sold and transported long distances. All that contributes to heavier use of existing high- tension lines and the construction of new lines. Given all that, I can't help but wonder that a study done say in 1965 is obsolete and would need to be redone reflecting all the above.
Date: Sat, 2 Jul 2011 09:40:54 -0700 (PDT) From: Lisa or Jeff <firstname.lastname@example.org> To: email@example.com. Subject: Re: Battery power support today Message-ID: <firstname.lastname@example.org> On Jun 29, 3:23 pm, AES <sieg...@stanford.edu> wrote: > Speaking for myself, based on my own technical and physical (though not > explicitly medical or biological) knowledge, I'm pretty damn sure that > cell phones simply do not and in fact physically can not cause > brain cancers, no matter how long you hold one against your skull. In a separate post, the govt says right now the biggest threat from cell phones is distraction while driving or walking. Yet people seem to be more worried about cancer than the real threat of distracted driving or walking out into traffic. It scares me how often I see people do hazardous things while driving or walking while talking on their cell phone. > But that said, would you yourself want to linger for very long "under an > AM Broadcast antenna holding a fluorescent light bulb that's glowing in > the RF field" as you describe above? Are there published standards for > acceptable rf field levels for humans working in close proximity to > high-power broadcast antennas? What's the field intensity in that > situation, compared to living next door to a cell tower with 8 or 10 or > even 20 antennas on it? Do the r-f intensities in your "glowing > fluorescent" situation approach levels where nonlinear effects, over and > above just simple heating, may start to appear in human flesh? Good questions, and the answers should be available. There are numerous developed hilltop communities that have had large powerful antenna in them for decades. I know of one community that had both an AT&T microwave antenna and a TV antenna (they were a few blocks apart). (The AT&T antenna is now a cell phone tower). Did residents or workers nearby (like the 7-11 in the shadow of the antenna) suffer increased health problems? Indeed, since this was a postwar baby boomer bedroom community, they could research both children who grew up near those antenna as well as their parents. Likewise, there are power lines and substations near residential areas. Again, did residents who lived close to those sources suffer health problems? Did workers who spent their entire career working in power plants suffer health problems?
Date: Sat, 2 Jul 2011 15:07:31 +0000 (UTC) From: David Scheidt <email@example.com> To: firstname.lastname@example.org. Subject: Re: Battery power support today Message-ID: <email@example.com> Sam Spade <firstname.lastname@example.org> wrote: :David Lesher wrote: :> Sam Spade <email@example.com> writes: :> :> :>>The exception was a pair-gain provision such as the Bell Systems SLC 96, :>>which was used in rural areas and in areas of rapid residential :>>construction. I believe the terminating SLC 96 box had to have local :>>power. Anyone know differently? :> :> :> Oh yes, SLC's need power. :> :> :>>I imagine SLC 96s are long gone for residential suburban areas :>>but they likely still exist in some rural areas. :> :> :> I was just in Aptos/Watsonville CA region, and there are :> SLC-96's on every other corner. The giveway is the line of :> shiny T1 repeater cans feeding same. :Both of those areas are a mix of suburban and remote rural areas. I can :understand the SLC 96 on a road back in the hills of Aptos where the :there are long distances with no houses, then a cluster of house. But, :if pair gain is being used in the suburban part of Aptos I would think :AT&T would be getting heat from the CPUC. Why? Modern nodes support all the services that are expected, like DSL, television, etc. They're fed with high speed backhaul (often fiber in dense areas). -- sig 92
Date: Sun, 3 Jul 2011 20:57:27 +0000 (UTC) From: David Lesher <firstname.lastname@example.org> To: email@example.com. Subject: Re: Battery power support today Message-ID: <firstname.lastname@example.org> David Scheidt <email@example.com> writes: >:Both of those areas are a mix of suburban and remote rural areas. I can >:understand the SLC 96 on a road back in the hills of Aptos where the >:there are long distances with no houses, then a cluster of house. But, >:if pair gain is being used in the suburban part of Aptos I would think >:AT&T would be getting heat from the CPUC. >Why? Modern nodes support all the services that are expected, like >DSL, television, etc. They're fed with high speed backhaul (often >fiber in dense areas). The CPUC regulates phone service. They have no control over DSL & beyond. It's up to PacBell  how they get get dialtone to 28 Barbary Line or similar. And since the DS1 fed SLC's are sunk cost; why would they change them out? As for "pair gain" in suburban parts; what's your definition of same? I saw several in areas that may not compete with the Upper East Side or tract-LA, but are not Death Vally -- take 'downtown' Corralitos, for one. And in urban areas, it's VERY commonly used; a typical hi-rise will have a LightSpan or other SONET-fed terminal in the basement. And thanks to Andrew for reminding me; I was pretty sure T's were powered with the +/- 130 series stunt, but could not find a good cite. Suffice to say it's enough so you know you got across something you shouldn't have... I seem to recall they could have 10-15 miles reaches easily; but the spec for signal [jitter etc, not power] went out to 150 miles. 1] or whatever their legal name is this week.
Date: Fri, 1 Jul 2011 09:24:59 -0700 From: Bruce Bergman <firstname.lastname@example.org> To: email@example.com. Subject: Re: Battery power support today Message-ID: <cANLkTikVpAAPE=aJ2V+DCSH2AE55ASj=bA@mail.gmail.com> > On Wed, 29 Jun 2011 12:23:18 -0700, AES <firstname.lastname@example.org> wrote: > > In article <BANLkTikg3_jasxgAbPLuJ5WqtABxNZVHKg@mail.gmail.com>, > Bruce Bergman <email@example.com> wrote: > > > You can walk around under an AM Broadcast antenna holding a fluorescent > > light bulb that's glowing in the RF field, especially at a 50KW Clear > > Channel blowtorch like KFI. > > Could you give your take on how this relates to currently on-going and > often very fervid debates over the (alleged) health hazards for people > and especially children caused by the r-f fields from cell towers in > residential neighborhoods, in church steeples, in close proximity to > schools, and so on? [Moderator snip] > ***** Moderator's Note ***** > > The reason Google - and every other source of information - is jammed > with scary information is that fear is a lot easier to generate than > electricity, and often leads to large research grants and/or speaking > fees for the academics who spread the rumors. The effects of ionizing > radiation on humans have been known and documented for decades. It all boils down to exposure levels and time. You simply need to put the antennas where the regions of ultra high RF fields are not readily accessible by people, and/or in places where they wouldn't naturally spend much time. There's a reason they fence off exclusion areas immediately under an omnidirectional broadcast tower, and it's only partly to keep people from trying to climb the tower - which would probably end badly anyway, as the would-be climber gets electrocuted to ground trying to climb over the huge ceramic base insulator. Also why the power coupling transformer for the navigation beacon looks like two interlinked hula hoops, so the RF voltage doesn't jump the 12" gap. They don't want you hanging out under the antenna in that zone of ultra high RF - which decreases logarithmically with distance, so the people working 2,000' away or living 3,000' away are fine. As to levels of microwave radiation around cellular tower sites, or the "Turnstile" antennas for Broadcast TV and FM radio - those are not omnidirectional antennas. The Sectional Panel antennas they hide in sets of three up in tall building elevator penthouses and church steeples and fake palm trees are rather directional and the vast majority of the energy is going out almost horizontally, there are no near-field issues in the building below them or ground level outside. Standing on the roof, inches in front of the antenna with the transmitters energized, is when it turns into a bad idea - which is why they lock the roof door. But rational discussion is not in the mind of the "Fear Uncertainty and Doubt" (FUD) Crowd, there's money to be made in selling you their book or the latest snake oil scam as protection. Or in the case of medical FUDsters like the "childhood vaccinations cause (Autism, etc.)..." crowd, they don't have the answers but they want to scare you away from beneficial vaccinations anyway. These people are about to unleash nasty things like Polio on the world again, because they have achieved a critical mass of unprotected children. I have a feeling the problem is in the thimerosal (mercury) preservative and they have been phasing it out, but we need to let science determine it for sure. --<< Bruce >>--
Date: Sat, 2 Jul 2011 20:43:17 -0400 From: T <firstname.lastname@example.org> To: email@example.com. Subject: Re: Battery power support today Message-ID: <MPG.firstname.lastname@example.org> In article <nc2dnZ7-tZKAeZPTnZ2dnUVZ_sCdnZ2d@giganews.com>, email@example.com says... > > David Lesher wrote: > > Sam Spade <firstname.lastname@example.org> writes: > > > > > >>The exception was a pair-gain provision such as the Bell Systems SLC 96, > >>which was used in rural areas and in areas of rapid residential > >>construction. I believe the terminating SLC 96 box had to have local > >>power. Anyone know differently? > > > > > > Oh yes, SLC's need power. > > > > > >>I imagine SLC 96s are long gone for residential suburban areas > >>but they likely still exist in some rural areas. > > > > > > I was just in Aptos/Watsonville CA region, and there are > > SLC-96's on every other corner. The giveway is the line of > > shiny T1 repeater cans feeding same. > > Both of those areas are a mix of suburban and remote rural areas. I can > understand the SLC 96 on a road back in the hills of Aptos where the > there are long distances with no houses, then a cluster of house. But, > if pair gain is being used in the suburban part of Aptos I would think > AT&T would be getting heat from the CPUC. Interestingly the only places I've ever seen pair-gain used is in the suburbs of RI. Never seen it used in the cities.
Date: Sun, 3 Jul 2011 09:15:09 -0700 From: Andrew Carey <email@example.com> To: firstname.lastname@example.org. Subject: [Obfuscate] Re: Battery power support today Message-ID: <19A9C82A-24AF-4090-BEDB-9AE475FF2FBE@ar-ballbat.org> > I've never seen T-carrier run off anything but loop voltage, aka > span power. That's why there's 130 vdc to bite you when you are > on the pair... > > And since that span power is appled by/at the CO.. T-carrier runs on a constant nominal 60mA current. Voltage can vary from 0 to 260VDC (+130VDC & -130VDC). The network inteface unit (NIU), which is the termination at the customer prem, can be span or locally powered. The line repeaters in between can be span powered in two ways. The standard way is straight through from one end, almost always from the central office. The other way is to set a line repeater in the middle to loop the power in both directions, which allow powering from both ends for extremely long spans. Note that this is for powering only, the signal flow is still end to end.
Date: Fri, 1 Jul 2011 10:59:42 -0700 (PDT) From: grumpy44134 <email@example.com> To: firstname.lastname@example.org. Subject: "Underground" demarc? Message-ID: <email@example.com> My friend is having an intermittent problem with her home phone. I told her to find the gray demarc/Telephone Network Interface (Ohio) box. After not being able to find it, she reminded me her power and telephone wires were underground to her house. Question - where is the demarc for underground telephone service (in Ohio)?
Date: Sun, 3 Jul 2011 17:20:51 -0400 From: Bill Horne <bill@horneQRM.net> To: firstname.lastname@example.org. Subject: Using DSO-DP channel units back-to-back Message-ID: <20110703212051.GC13805@telecom.csail.mit.edu> I've been told that some LEC's use DSO-DP channel units back-to-back, to connect one channel bank to another when they have a voice-only circuit that needs to go through a "tandem point" office. Now, theorietically, this should work, but I can't shake the feeling that DSO-DP's shouldn't be used for tandem service, probably because I've never seen it done before. Any T-1 engineers out there? Is there a reason why DSO-DP CU's aren't the best choice for tandem service, i.e., that a 4ETO or TDM unit would work better? I understand that DSO-DP's won't carry signalling from one T-1 bank to another, but are they adequate for voice-only circuits? Inquiring minds want to know. ;-) Bill -- Bill Horne (Filter QRM for direct replies)
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