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Density.io

density.io

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Re: Density.io

#81

Post by billyhoffman »

silvertonia wrote: post #70
Robin_Message wrote: post #24

This idea is cool, but there are some issues with their privacy claim. They say they are hashing the MAC address (presumably on the device). However, they can't be salting the hash (else they wouldn't be able to match across different stores). Since there is no salt (or a fixed salt), it is trivial to de-anonymise a specific MAC address (just hash it and see if any server has it). Worse, there are only 46 bits that a…

why not salt and store the salt with the hash?

The whole point is the customers in your store have nothing on there phones. Their device simply sucking down the MAC that is broadcast. They are going to get the unprotected MAC.

Re: Density.io

#82

Post by simpsond »

While I understand the concern about tracking peoples presence with phones, I don't feel like this is new. The cellular companies can track location, and it's already happening.

Re: Density.io

#84

Post by skywhopper »

jws wrote: post #40
paulgb wrote: post #13

Earlier quoted context omitted.

What's the advantage to a constant MAC address anyway? There must be a reason for it, but my first reaction to this article was to see if I could change mine.

At the link level, your MAC is your unique address. First: You do not want a MAC collision. I have worked with hardware that sometimes picked a non-unique MAC and your life gets really weird and sucks away a lot of debugging time to find out why impossible things are happening. Continuing – It made ethernet easy to implement. They could have added some complicated address negotiation protocol and then handled address…

Wifi drivers could easily deal with this risk by providing specific MAC addresses only to specific networks. So you lock in your home network and work network, but randomize other unknown WAPs. Or better yet, just turn off wifi when you're away from trusted WAPs and use your cellular data.

Re: Density.io

#85

Post by ZoF »

650REDHAIR wrote: post #37
icebraining wrote: post #34

Earlier quoted context omitted.

How will you know?

I guess I have to start looking towards outlets. I wonder if there is any other way to 'protect' yourself?

Spoof your MAC address, use airplane mode, there's other ways I'm sure.

Agreed, this seems invasive and I dislike it.

Re: Density.io

#87

Post by tzakrajs »

nwh wrote: post #66

Keep in mind that these "anonymous" data points aren't. Your phones MAC address exposes your home wifi network thanks to Google's databases. They also expose where you work, where your friends houses are, what your favorite coffee shop is. This is beyond dangerous, it's completely unacceptable.

I am confused where you are linking MAC addresses of phones with MAC addresses of home wireless routers.

Re: Density.io

#88

Post by slackpad »

Are there any good apps for location-aware WiFi toggling? I rarely use WiFi outside of home or work so I'd like it to turn itself off to avoid stuff like this.

Re: Density.io

#89

Post by nwh »

tzakrajs wrote: post #87
nwh wrote: post #66

Keep in mind that these "anonymous" data points aren't. Your phones MAC address exposes your home wifi network thanks to Google's databases. They also expose where you work, where your friends houses are, what your favorite coffee shop is. This is beyond dangerous, it's completely unacceptable.

I am confused where you are linking MAC addresses of phones with MAC addresses of home wireless routers.

Your devices broadcast the names of networks it has seen recently in frequent intervals. "Yo HomeWiFI you there" essentially. Anybody listening can then correlate them with Googles database to find out detailed information about the user. Usually people have a huge list of connected networks which will be announced and give huge information about the user. "MIT" SSID? Probably a student then.

Re: Density.io

#90

Post by beejiu »

chrisfarms wrote: post #5

Risky. MAC address tracking is definitely a legal 'grey area' at the moment. I can imagine mining/fingerprinting in this way could easily become illegal in the not-to-distant future. In the UK, City of London already banned the wifi-enabled bins that were tracking MAC addresses. It would be really easy to tie a name to MAC address (from point of purchase with a credit card), then see exactly where that person went vi…

There are 500,000 CCTV cameras in London, and we are concerned about a few hundred advert-bins counting how many people are nearby...
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