How malformed packets caused CenturyLink’s 37-hour, nationwide outage

The switching module sent these malformed packets “as network management instructions to a line module,” and the packets “were delivered to all connected nodes,” the FCC said. Each node that received the packet then “retransmitted the packet to all its connected nodes.”

Source: How malformed packets caused CenturyLink’s 37-hour, nationwide outage | Ars Technica

But the outage continued because “the malformed packets continued to replicate and transit the network, generating more packets as they echoed from node to node,” the FCC wrote. Just after midnight, at least 20 hours after the problem began, CenturyLink engineers “began instructing nodes to no longer acknowledge the malformed packets.” They also “disabled the proprietary management channel, preventing it from further transmitting the malformed packets.”

Counterintuitive physics property found to be widespread in living organisms

Ever since the late 19th century, physicists have known about a counterintuitive property of some electric circuits called negative resistance. Typically, increasing the voltage in a circuit causes the electric current to increase as well. But under some conditions, increasing the voltage can cause the current to decrease instead. This basically means that pushing harder on the electric charges actually slows them down

Source: Counterintuitive physics property found to be widespread in living organisms

Why putting a script in /etc/cron.hourly is not working?

As you’ve probably seen in the comments to your question, the cronjobs in /etc/cron.hourly (and the other, similar directories) are executed by run-parts. run-parts is a little picky about filenames. By default it doesn’t execute files whose filenames contain anything other than (all of those from ASCII)

  • uppercase letters
  • lowercase letters
  • digits
  • underscores
  • dashes (“minus signs”)

So if your script has a filename of for example “myscript.sh”, it just is ignored, because run-parts does not like the dot.

Source: Why putting a script in /etc/cron.hourly is not working? – Ask Ubuntu

LOL!

Facebook (FB) Paid Contractors to Transcribe User Audio Files

In follow-up answers for Congress, the company said it “only accesses users’ microphone if the user has given our app permission and if they are actively using a specific feature that requires audio (like voice messaging features.)” The Menlo Park, California-based company doesn’t address what happens to the audio afterward.

Source: Facebook (FB) Paid Contractors to Transcribe User Audio Files – Bloomberg

Facebook first started allowing Messenger users to have their audio transcribed in 2015. “We’re always working on ways to make Messenger more useful,” David Marcus, the executive in charge of the service at the time, said in a Facebook post.

Scientists invented air conditioners for the climate change age

Their invention looks a lot like a solar panel. A flat metal panel is covered in a sheet of the material—a high-tech film—the trio invented. The material reflects the light and heat of the sun so effectively that the temperature beneath the film can drop 5 to 10-degrees Celsius (9 to 18-degrees Fahrenheit) lower than the air around it. A system of pipes behind the metal panel are exposed to that colder temperature, cooling the fluid inside before it’s sent out to current-day refrigeration systems.

Source: Scientists invented air conditioners for the climate change age — Quartz

Why NASA Should Bake Cookies in Space

Those hotel chocolate-chip cookies will be the closest astronauts have come to truly baking something in their high-flying kitchens. NASA says astronauts won’t actually eat the cookies, because they are, technically, a science experiment. The treats will be returned home for examination.

Source: Why NASA Should Bake Cookies in Space – The Atlantic

NanoRacks created a cylinder-shaped oven lined with heating components that can bring the interior temperature to 350 degrees Fahrenheit. It bakes one slab of cookie dough, which is held in place inside a sealed tray, at a time. The oven will plug into an apparatus about the size of carry-on luggage that supports scientific experiments with electricity, cooling, and other needs.

RSA in 5 lines of perl

#!/usr/local/bin/perl -s do 'bigint.pl';

($_,$n)=@ARGV;s/^.(..)*$/0$&/;

($k=unpack('B*',pack('H*',$_)))=~ s/^0*//;

$x=0;$z=$n=~s/./$x=&badd(&bmul($x,16),hex$&)/ge;

while(read(STDIN,$_,$w =((2*$d-1+$z)&~1)/2)){$r=1;$_=substr($_."\0"x$w,$c=0,$w);

s/.|\n/$c=&badd(&bmul ($c,256),ord$&)/ge;$_=$k;s/./$r=&bmod(&bmul($r,$r),$x),$&?$r=&bmod(&bmul($r,$c ),$x):0,""/ge;($r,$t)=&bdiv($r,256),$_=pack(C,$t).$_ while$w--+1-2*$d;print}

Source: RSA in 5 lines of perl

A DIY Internet Network Has Drastically Expanded Its Coverage in NYC

Initially, the mesh network was powered by a single “Supernode” antenna and hardware array located at 375 Pearl Street in Manhattan. This gigabit fiber-fed antenna connects 300 buildings, where members have mounted routers on a rooftop or near a window. These local “nodes” in turn connect to an internet exchange point—without the need for a traditional ISP.

Source: A DIY Internet Network Has Drastically Expanded Its Coverage in NYC – VICE