40 Years of the Digest ... founded August 21, 1981
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The Telecom Digest for Fri, 21 Jan 2022
Volume 41 : Issue 15 : "text" format

table of contents
cyber attack against International Red Cross
Re: Why are airlines predicting doom and gloom about 5G?
A Look Back at 2021 and CTN Predictions for 2022
Re: Why are airlines predicting doom and gloom about 5G?

Message-ID: <Pine.NEB.4.64.2201200649310.28061@panix1.panix.com> Date: 20 Jan 2022 06:49:55 +0000 From: "danny burstein" <dannyb@panix.com> Subject: cyber attack against International Red Cross [ICRC posting] Sophisticated cyber-attack targets Red Cross Red Crescent data on 500,000 people A sophisticated cyber security attack against computer servers hosting information held by the International Committee of the Red Cross (ICRC) was detected this week. The attack compromised personal data and confidential information on more than 515,000 highly vulnerable people, including those separated from their families due to conflict, migration and disaster, missing persons and their families, and people in detention. The data originated from at least 60 Red Cross and Red Crescent National Societies around the world. The ICRC's most pressing concern following this attack is the potential risks that come with this breach -- including confidential information being shared publicly -- for people that the Red Cross and Red Crescent network seeks to protect and assist, as well as their families. When people go missing, the anguish and uncertainty for their families and friends is intense. ====== rest: https://www.icrc.org/en/document/sophisticated-cyber-attack-targets-red-cross-red-crescent-data-500000-people _____________________________________________________ Knowledge may be power, but communications is the key dannyb@panix.com [to foil spammers, my address has been double rot-13 encoded]
Message-ID: <20220120222644.E8588354AD21@ary.qy> Date: 20 Jan 2022 17:26:44 -0500 From: "John Levine" <johnl@iecc.com> Subject: Re: Why are airlines predicting doom and gloom about 5G? It appears that Bill Horne <malQRMassimilation@gmail.com> said: >Ergo, why the fuss? > > * Are the avionics salesmen trying to create a firestorm of fear that > motivates airlines to buy brand new radar altimeters? To some degree, but a lot of it is "everything was fine until you guys showed up" and the FAA doesn't understand radios very well. The first study of interference with identified equipment only showed up a couple of weeks ago, after years of duelling press releases. > * Do the old altimeters have substandard design? Definitely. > * Is the cellular industry choosing to ignore known risks? It depends on your definition of known risks. There are duelling studies, the risks look pretty low to me, particularly if the telcos limit power in cells near runways which would not be a big deal. > * Is it all a ploy by the cellular carriers to grab more spectrum for > cheaper prices? Check how much they paid for C-band in the spectrum auction and you'll know the answer to that one. Heck, no. But they may end up paying a lot more if they're stuck with the cost of replacing every 30 year old altimiter in the country. R's, John
Message-ID: <d4ee8933-5ff0-477b-ab68-f4b9de6bf836n@googlegroups.com> Date: 19 Jan 2022 22:50:54 -0800 From: "Colin Sutton" <colin_sutton@ieee.org> Subject: A Look Back at 2021 and CTN Predictions for 2022 A review from the the IEEE communications society written by the CTN Editorial Board and Alan Gatherer, Guest Editor may be of interest: https://www.comsoc.org/publications/ctn/look-back-2021-and-our-predictions-2022
Message-ID: <courier.0000000061E9C2F5.002225E0@coop.radagast.org> Date: 20 Jan 2022 12:15:49 -0800 From: "Dave Platt" <dplatt@radagast.org> Subject: Re: Why are airlines predicting doom and gloom about 5G? >Here's the point that I'm confused about: according to the podcast, the >cellular authorizations go up to 3.98 GHz, and the aircraft altimeters >that we're hearing all these dire warnings about are assigned to a range >which starts at 4.2 GHz. I'm old-school, admittedly, but having 220 MHz >of "guard" space between those two services seems adequate to me. >Interim moderator's response: > >The problem is that the FAA standards for altimeters required them to >exclude signals from "more than 10%" away. That's 420 MHz of allowable >sloop in the receiver. They made that standard in 1983 and never updated >it. Many altimeters are better than that, but some apparently aren't, or >aren't much better, so they can pick up signals from 3.8-3.98 GHz. There's a graphic showing that portion of the spectrum in the article at: https://www.aviationtoday.com/2021/12/23/faa-issues-new-radar-altimeter-5g-c-band-risk-assessment-request-aviation-industry/ The "Typical RA filter tolerance mask" as shown there (without a dB scale, alas) is quite broad, and the 5G emission strength shown is quite high (higher than the radar-altimeter emissions, and far higher than the satellite signals previously used in that part of C band). I haven't found a document yet which shows the actual emissions strengths and masks with an accurate scale. My guess is that the problem with some altimeters may be one of "desense" (de-sensitization). If the altimeter receiver doesn't have sharp filters before its first active gain/detector stage, the out-of-band signal can saturate the gain stage, and this reduces the gain for the desired in-band signals. In effect, the radar reflections "go away" when the altimeter enters the area on which 5G emissions are strong. To use an audio analogy: you can't hear the piccolo, when the bass guitarist has cranked the volume up to 20 and the amplifier is clipping and the speaker cones is being driven to its limit. Filtering at a later point in the chain, after the point of amplifier clipping, doesn't help. It's also possible in principle for multiple, strong out-of-band signals to mix (heterodyne) inside the receiver, creating spurious signal products inside the altimeter bandwidth and "confusing" the altimeter. It's surely possible to build altimeters with the necessary filtering, and to replace existing altimeters with better ones, but that will take a long time and cost a pretty penny. There seem to be two issues here in the US which are making this problem more severe than in Europe: the authorized 5G C-band emission limits are higher, and the C-band antennas here aren't required to have a "down-tilt" pattern to limit their emissions to mostly "below the horizon". So, when a plane is in its landing pattern (which is where you'd most want the altimeter to be working correctly) it will enter the area where the altimeter is most likely to be overloaded by strong C-band 5G signals.

End of telecom Digest Fri, 21 Jan 2022

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