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Testing Phone-Sized Faraday Bags

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Re: Testing Phone-Sized Faraday Bags

#161

Post by mrguyorama »

theshrike79 wrote: post #143
SamuelAdams wrote: post #57

This is a super cool blog post. However I think it alludes to a much larger problem. For many products today, it’s very difficult or impossible for most people to verify the product works. For a network switch, there are free and open source tools like iPerf to test and verify speeds are as advertised. For a faraday box, you have to go through all these steps (and knowledge learned) just to be able to test these. Wha…

Linus Tech Tips is attempting something in this field: https://www.youtube.com/watch?v=pt3-6BsWlPk tl;dw They're building a setup where they can test a bunch of computer equipment with standardised tests (built by them) in a standardised environment (also built by themselves).

Gamer's Nexus, also on youtube, has done something very similar and designed a bunch of "Standardized" tests for their benchmarks of computer systems and hardware

Re: Testing Phone-Sized Faraday Bags

#162

Post by Tronno »

What's the use case for these products?

Even if the radio is blocked, how does that stop a device from collecting data anyway, and exfiltrating it the moment it finds a network? Won't it look for a network the moment you take it out of the bag? And don't you have to remove it from the bag to use it practically?

Ultimately, if your device is compromised or untrustworthy to the extent that it has to be policed this way, is it not safer to just... get rid of it?

Re: Testing Phone-Sized Faraday Bags

#163

Post by kurthr »

pdkl95 wrote: post #15

I really like Snowden's recommended Faraday cage for phones or other devices of similar size: two drink-shaker cups[1]. Drink shakers are cheap and widely available. The average hotel room in any medium/large hotel chain probably includes a shaker as a standard item as part of the minibar. The simple two-cup style (as seen in [1]) is preferred over the fancier "strainer top" style because you can press the two cups t…

If you're interested in simple cages similar in effectiveness to the EDEC Window Pouch (they drop off above 3GHz)... try a Microwave Oven. They are highly available, reasonably convenient and well designed, with pretty good quality control. You can even still see your phone inside has zero bars. I do, however, recommend unplugging the microwave (or even cutting the power cord) as a fire would likely result from cooking your hardware.

To answer [2] How big are the waves you're trying to block? - it's actually crack length not width that usually determines the effective re-radiating antenna length. They can be very narrow, but a long (a few cm) crack will allow one polarization through almost completely.

I've run this test with a GSM base station and confirmed the effectiveness. If you want to test communication with a device to a base station, but have many other local antennas interfering and want to fit many devices inside... it's a decent choice. The alternatives are less convenient and usually thousands of dollars to construct.

Re: Testing Phone-Sized Faraday Bags

#164

Post by _0w8t »

wilkommen wrote: post #116
sdoering wrote: post #100

Earlier quoted context omitted.

I agree that the free market is easily gamed and therefore I really am glad to be living in a country with relatively strong consumer protection laws. I buy online, I can return within two weeks no question asked. It breaks within two years - I return it. Either I get a repaired one or a new one or my money back. There are few exceptions but mostly it makes shopping quite secure. Yes. There are bad actors. Yes people…

What country do you live in?

Norway has similar 14 day return right for things ordered online. It is originated in eighties when the phone or postal orders became popular. Basically if you do not have a chance to examine the thing one is getting like in a physical shop, the seller must accept returns within 14 days. This cannot be restricted to unopened or unused things.

Re: Testing Phone-Sized Faraday Bags

#165

Post by srcreigh »

ghshephard wrote: post #155
GordonS wrote: post #108

Earlier quoted context omitted.

> The average hotel room in any medium/large hotel chain probably includes a shaker as a standard item as part of the minibar I've stayed in dozens of hotels all over the world, and never once have I seen a cocktail shaker in the minibar?!

I've stayed in over a hundred, frequently in suites (upgrades), often at 4* hotels, in 22 countries (Full set of brands - Marriot, Hyatt, JW, etc...) Ice Buckets are pretty common - but I have never once seen a drink shaker in a room mini-bar.

The Fairmont Royal York in Toronto has shaker cups. It is 5-star though.

Re: Testing Phone-Sized Faraday Bags

#166

Post by throwaway1777 »

yosito wrote: post #152
24bug47 wrote: post #129

Earlier quoted context omitted.

You would take out your phone if you would like to make a phone call, or check to see if you have received any messages. For the other 99% of your day, the IoT sensors being stuck on every conceivable object are unable to report back to HQ (and every agency and broker affiliated) your current whereabouts and trajectory.

So why not get a more basic phone and not a smart phone?

Dumb phones still ping cell towers?

Re: Testing Phone-Sized Faraday Bags

#167

Post by newaccount74 »

throw10920 wrote: post #137
SamuelAdams wrote: post #57

This is a super cool blog post. However I think it alludes to a much larger problem. For many products today, it’s very difficult or impossible for most people to verify the product works. For a network switch, there are free and open source tools like iPerf to test and verify speeds are as advertised. For a faraday box, you have to go through all these steps (and knowledge learned) just to be able to test these. Wha…

I'd like to describe a complementary problem to yours - that it's very difficult or impossible to find out others' experiences with a product's quality, durability, and performance. That is - the complement to the problem of "it's hard to determine if some products work" is "it's hard to find other users' experiences with the product". Amazon reviews are completely worthless, but very few other platforms have anywher…

> because consumers don't care about these things

I think that's not the issue. Consumers DO care about durable products, and consumers DO share their experience. Consumers talk to others about stuff they like all the time, and they also complain to others when stuff doesn't work. Consumers also spend a lot of time online researching products.

Amazon Reviews were amazing in the beginning, because so many customers shared their honest experience.

The problem is that as soon as there is a popular place where people go to read reviews, companies realise they can make a lot of money if they post fraudulent reviews (or send free samples to folks who write positive reviews). Products with good reviews make lots of money, so companies are going to put a lot of effort into getting good reviews.

On the other hand, consumers trying to share their honest experience don't have anything to gain from doing so, so they are not going to put as much effort into sharing their experience.

Re: Testing Phone-Sized Faraday Bags

#169

Post by Tijdreiziger »

throw10920 wrote: post #137
SamuelAdams wrote: post #57

This is a super cool blog post. However I think it alludes to a much larger problem. For many products today, it’s very difficult or impossible for most people to verify the product works. For a network switch, there are free and open source tools like iPerf to test and verify speeds are as advertised. For a faraday box, you have to go through all these steps (and knowledge learned) just to be able to test these. Wha…

I'd like to describe a complementary problem to yours - that it's very difficult or impossible to find out others' experiences with a product's quality, durability, and performance. That is - the complement to the problem of "it's hard to determine if some products work" is "it's hard to find other users' experiences with the product". Amazon reviews are completely worthless, but very few other platforms have anywher…

Amazon and Coolblue reviews have been decent for me. With Amazon, the nice thing is that even if there aren't any reviews on your local Amazon, it will show reviews from other countries' Amazons with the option to translate. Combine that with professional review sites like Rtings or The Wirecutter and you can usually get a decent idea.

Re: Testing Phone-Sized Faraday Bags

#170

Post by yosito »

throwaway1777 wrote: post #166
yosito wrote: post #152

Earlier quoted context omitted.

So why not get a more basic phone and not a smart phone?

Dumb phones still ping cell towers?

Sure, but they also have simpler hardware that's easier to audit and almost all have removable batteries, which is most likely just as effective as a faraday bag.
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