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Encoding your WiFi access point password into a QR code

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121–130 of 234 posts

Re: Encoding your WiFi access point password into a QR code

#121
post #80
post #39

I painted my wifi password as a QR code on 40x40cm canvas.. Painted as in with a brush and paint, it was a bit of work, but now it's both pragmatic and pretty :)

If you change the password, will you repaint the picture?

It's just a guest network...

Who cares if my neighbors or people walking by can use it?

Re: Encoding your WiFi access point password into a QR code

#122
post #49
post #39

I painted my wifi password as a QR code on 40x40cm canvas.. Painted as in with a brush and paint, it was a bit of work, but now it's both pragmatic and pretty :)

So that it is visible from the street...

No, but how well do you really need to secure your guest network?

If people want anonymous WiFi for nefarious purposes they can go to a cafe.

Re: Encoding your WiFi access point password into a QR code

#123

Earlier quoted context omitted.

They can’t be used to encode very much data though. They wouldn’t be suitable for storing documents, but could be used to store the location of a document. I was trying to be clever once and thought I could encode X.509 certificates in QR codes. Even that much data was pushing the hard limits of what they can store, and became very hard to scan (I quickly realised this wasn’t actually very clever).

7kb for a supermarket bill is plenty, and you can have several of them. Forms and legal documents should all have an immutable official url and uuid anyway to point to their legal and administrative context.

The largest QR code in the standard, "version 40" - can only store 3 kilobytes at the lowest level of error correction and 1.2 kilobytes at the highest level [1]. And that's a pretty huge QR code [2]

My back-of-the-envelope calculations say you'd need 61 bits per line on a receipt just to encode UPC, quantity and price. So the largest QR code would only allow 19-50 lines. And that's without including data like the store name, special offers, means of payment and so on. Believe me, plenty of people buy more than 50 items in their supermarket christmas shop :)

Standardised digital receipts would be neat but, QR codes encoding the data ain't the way to go about it.

[1] https://www.qrcode.com/en/about/version.html [2] https://commons.wikimedia.org/wiki/File:Qr-code-ver-40.svg

Re: Encoding your WiFi access point password into a QR code

#124

Most ISP put this kind of QR code on the provided "modem" in France with the default Wifi password of the device. I love QR code. I think it should be everywhere. All legal documents and forms should have one. All supermarket bills should have one. It's a fantastic way to transition from paper to bits. Unfortunately most users have no idea what it is. They don't know what a URL is, so a QR code is out of the question…

Are you not concerned that QR code’s are just completely opaque URLs asking to be clicked? Do you confidently click on URLs in spam emails? Of course not since we all know URLs can point to malicious payloads. So why should we love QR code’s that could just as easily do the same. If I’m a spammer trying to get people to click on my bogus links in my email messages, why wouldn’t I also print those same URLs as QR code…

Do you never click URLs in emails? Of course you do, when you're confident the sender is reputable.

Parent was referencing trusted contexts: the default password printed on your wifi router, the bill a cashier just handed you for what you just bought, the legal papers you just signed, etc. The QR code just links the trusted document with trustworthy digital versions & extended content.

I'm not worried a spammer is going to get a bogus QR printed on the grocery store receipt I just received. I'm not going to scan QR codes printed & posted on subway walls for no apparent reason.

Re: Encoding your WiFi access point password into a QR code

#125
post #68

Earlier quoted context omitted.

firefox preview has an embedded qrcode scanner

For url only. Qrcode are for much more than url.

You either use URL or custom app to scan Qrcode. You can't encode arbitrary data and expect universal reader being able to interpret it. And URL is actually good way to store small amounts of data, because you can launch web app to handle it and it's compatible with any device.

Re: Encoding your WiFi access point password into a QR code

#126
post #85

Earlier quoted context omitted.

No more than regular url written in a paper. People write them blindly anyway, they don't know what it means nor how to read it. But QR code are not just for URL, they can contain up to 7k, which is a lot for text and numbers. And you can have several of them, use compression, etc.

Because urls have letters & words in english that I can read and determine if the website is authentic or not as opposed to QR code that no human can read? Have you never come across phishing scams that looked eerily authentic only to be clued in by the fake url? I can read the URL before going to the website, and unless QR codes have a step where you have to manually confirm going to the url provided by the code (mo…

Because urls have letters & words in english that I can read and determine if the website is authentic

You must have some super-human ability to read a computer's mind if you can grok the kind of urls that usually come in emails like https://tinyurl.com/uvc58uq

Re: Encoding your WiFi access point password into a QR code

#127
I really think manufacturers have really missed out on an opportunity with QR codes by handing them over to marketing. Most of the early QR codes in the US were just links to advertising. I'm not going out of my way to scan a QR code just to be advertised to.

On the other hand it could have been a great way to develop much better relationships with your customers. As a trivial example, I own a snowblower. It would be nice if there had been a QR code on the machine that identified that specific machine. I could have scanned it and immediately registered it with the manufacturer. Scanning the code could take you to a manufacturer page for your specific machine, where you could record routine maintenance like oil changes, get a copy of the manual, and order replacement parts. They could send you periodic reminders like, "it looks like it's been a while since an oil change", or "it's getting cold outside. Now's a good time to make sure everything is in shape".

There is a ton of stuff around the house that I need to record information about but have to have my own system. If the manufacturer provided a way to do that they could offer their expertise with the product and a convenient way for you to record that information. I'd love to have a QR code on the side of my HVAC system, water heater, filtration system, etc.

Re: Encoding your WiFi access point password into a QR code

#128

Earlier quoted context omitted.

Or is it extra safety to use the CLI? Arguably it is easier to verify that a webapp is not sending the data to a 3rd party, than it is to verify that the CLI tool doesn't (easy network inspection from the developer tools).

Its also very easy to put a webapp into offline mode

How do you do that? Private browsing + cut ethernet?

Re: Encoding your WiFi access point password into a QR code

#129
post #71
post #66

Earlier quoted context omitted.

They already have all passwords... They are conveniently backed up on android devices. They have the cleartext. (as do apple btw.)

Apple's WiFi password sharing system uses iCloud Keychain, which is end-to-end encrypted [1] [1] https://support.apple.com/en-us/HT202303

As long as Apple can run arbitrary code on your device, protocols do not matter.

Re: Encoding your WiFi access point password into a QR code

#130
post #2

Why would I want to make it EASIER for people coming over to use my WiFi?

You don’t give your WiFi password to everyone that visits?

These days everyone have 4G internet, so there's no point to giving your WiFi password to everyone.
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