Schneier on Security

Clive Robinson • August 3, 2022 8:31 AM

@ All,

I kind of expected it to become common.

Stopping it is not going to be easy because there is enough incentive involved to turn it into “an arms race”.

Any second year undergraduate studying the likes of aerospace, electronics and similar will have the skill set to design a drone system that can beat the current anti-drone systems around.

The current conflict at the far easten edge of Europe is pushing the drone boundries / capabilities forwards dramatically (all modetn wars cause techbology pushes).

Which means that such technology will be on the black market imminently.

Whilst this is currently a “prisons” issue, consider what woukd happen to SWAT teams etc in stand offs?

Then take that forward into other areas of National Security concerne.

After all conceptually what is the difference between a half million dollar “Cruise Missile” and a $1000 drone with autopilot and a 1kg payload?

Remember I’ve been thinking about this sort of thing for deterance purposes since the mid 1980’s when Radio Control systems were used in Northern Ireland to detonate hidden bombs. I made the mistake of pointing out to superiors that you could make an RC plane with a sixfoot wingspan that could lift a 5lb load, that would obviate what was then their current defence ideas. Worse I went on to show that you could not reliably stop such aerial attack decices, and you still can not…

So an arms-race looks like it is most definitely going to happen…

Clive Robinson • August 3, 2022 12:39 PM

@ Winter, Peter A, ALL,

With regards,

“anti-contraband Prison Netting solutions”

The operative word is “netting” which is an interesting problem…

In many places one of the few rights prisoners get is access to excercise in fresh air and daylight, that is to in effect be “out doors”.

Thus “netting” can be used but solid ceilings made of say glass can not be used.

Then there is the issue that high value contraband such as mobile phones can be very small and other contraband can be formed into small but long cylinders, wraps, ropes or strings of quite narrow diameter.

For instance I have a couple of very small 2G Phones from China, I bought in London’s Tottenham Court Road for cash no questions asked, nor was video taken of the purchase.

One phone is still in it’s original case that is less than half an inch wide, a third of an inch deep, and an inch long. It looks like a dolls toy, but it’s fully functional including the key pad[1].

So will drop through a lot of netting systems without any problems if pushed correctly. They just have to be retrieved and hidden[2] by a prisoner.

The problem for the net designers is if they make the holes to small then leaves and other materials that will rot or in otherways become significant health hazards get caught if not cause water run off damage to buildings… Whilst in non prison settings cleaning such nets would be possible without much risk…

I’m told that such a small mobile phone can earn more than $1500/month income in US prisons which is actually a colosal amount[4].

The point is though that such netting has technical limitations that depend on a number of factors. And won’t of necessity be able to stop the size of high value contraband a drone can “push through and drop”.

[1] The other phone I’ve taken out of it’s case and connected it up to a tiny microprocessor which can tap into USB. It all fits into a largish pen cap just like one of those give away thumb drives. I use both phones when giving lectures to show just how little is needed to perform surveillance from the other side of the world. Worse just how easy it is to get hold of suitable consumer tech for less than “pocket change” and modify it to do so (it scares a lot of people including some pen-testers). I then go on and show other consumer level tech such as “Software Defined Radio”(SDR) systems that are equally as inexpensive and as easily available, to not just find but jam/neutralize such threats.

[2] Such small phones can be fairly easily hidden in body cavities[3]. Whilst many have heard of the obvious ones, they might not of heard of putting it in a bag and swallowing it. Thus the prisoner can wait for it to pass. However they can also tie it to a length of dental floss that the other end is fixed to their back teeth. Thus it sits in the stomach and can be pulled up again fairly easily with practice.

[3] I’ve not actually seen it done, but I’ve heard about it through people who have tried to “cyber enhance” themselves. Apparently you can without too much difficulty create a hidden pouch… It was found out by people that have surgically inserted RFIDs, Magnets and much larger active electronics into themselves. The result the body creats a fibroid around it and this can be lined as a permanent hidden pouch like cavity… The idea scares me because the bodies natural defences have effectively been breached thus the risk of infection would be high.

[4] The way to stop this to break the artificial monopoly created by the “Prison Phone” companies who profit at well upwards of 5000% and record all prisoners conversations and then sell them to Law Enforcment and other Agencies. That in the normal course of events would not be able to eavesdrop on such conversations.

Clive Robinson • August 7, 2022 7:28 PM

@ ALL,

Re : Drone drops and observation.

As I noted above,

“The current conflict at the far eastern edge of Europe is pushing the drone boundries / capabilities forwards dramatically (all modern wars cause technology pushes).”

Thus two questions arise,

1, What capabilities now and in the near future.
2, How to negate the benitits it gives to others.

The following to videos, are various things considered usefull viewing,

The first is a general overview and update on what is comming back from the far eastern edge of europe,

https://m.youtube.com/watch?v=zHnkUHsliSg

This second –earlier– video is on a future subject for sUAS commercial or consumer drones. “Synthetic Apature Radar”(SAR) is a technically complex subject, however think of it as a camera using radio wavew rather than light, that can also measure distance to such a small amount it can see soft tire vehicle tracks on hard dusty ground by the depth distances.

SAR was “a thing on jumbo jets” bot so long ago, but is now capable of being put on larger drones. Within half a decade I can see it being sufficiently small to be put on commercial drones that can carry a 1kg or above payload.

https://m.youtube.com/watch?v=dOoCltqtJR8

What neither video mentions and it is important is that ground troup OPSec involving radio communications has to significantly change.

The military still have not updated on the issues with HF, VHF, UHF and microwave systems.

The assumption being that enemy radio location forces are “ground based” thus have a very close “radio horizon” is now nolonger true.

Gum-stick Linux computers are well below $50 and are very small and if ARM based tend to be quite low power. They can be fitted with veru small and light WiFi or Mobile Broad bsnd USB devices weighing just a few grams as well as the likes of RTL “Software Defined Radios”(SDR).

Basically giving quite exceptional ElInt and SigInt “head end” capabilits for a little under $100. That can be hung from a larger consumer drone which can fly at a hight of upto 300m. Thus the “radio horizon” would be over 60km.

So even on very low transmission power of 10mW as it’s “line of sight” it will be picked up at 60km by the drone. Where as a squad of dispetsed soldiers over a 100m diameter area who are “ground hugging” because they are not line of sight, would be hard pressed to communicate…

Back in the 1980’s I took advantage of this, if you look up the “Epsom Downs Race Course” you will see it is has a high stand mounted at a high point of the downs. There was a 2m VHF Amateur Radio Repeater that you could use from there with just 1W from a hand held walkie talkie (Icom IC2E) and the standard inefficient “rubber duck” antenna. That repeater was also usable by people in cars on the Isle of Wight… and I regularly went “up the downs” with a much more efficient “folded dipole” and could get into the repeater from a “grassy knoll” up towards Tatenham Corner using only 150mW and chatted to people I knew from the Royal Yacht Club in Cowes…

I know of people on current construction sites that are at most 100m wide who can not get reliable VHF communications with hand held / Walkie Talkies pushing out more than 5W…

That “line of sight” makes a very significant difference, and for troops on the ground a couple of drones they can neither see nor hear can fix their location dead within seconds the moment one of them presses that “Push To Talk”(PTT) button…

Clive Robinson • August 8, 2022 6:59 AM

@ Winter, ALL,

… the same people who want to deploy such drones will also find ways around this.

To mis quote a ScFi character,

“Yer canny defie the laws of science Capt’n”

To communicate in our physical universe “information” has to be imprinted / modulated on matter or energy.

If it’s energy in the form of photons then we know two things about them,

1, They move at the speed of light.
2, They only change direction when acted upon by a force.

We also know that try as hard as we might, photons do not remain phase coherent and they do diverge.

We also know when it comes to physical objects a photon suffers in one of three ways,

1, It passes through : Transmission.
2, It bounces off : Reflection
3, It is captured : Absorption.

Whilst the first two are relatively simple effects and their bulk effects can be worked out with Euclidean Geometry, the third can be hellishly more complicated and involves processes like “Radiation transport” where the photon energy gets down stepped to basic mechanical vibration at the atomic scale we call heat or re-emitted at a lower frequency in an apparently random direction.

So making communications covert is at best difficult.

Also there is the information “Bandwidth Energy” issue. Basically the more information you wish to send, the greater the bandwidth required which in turn means the more energy required. Also as wanted signal bandwidth and time are inversly proportional the faster you want to send information the more energy you need…

Thus the more energy there is to inadvertantly escape and be detected by an opposing force…