Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Density.io

density.io

Post reply on HN
Print view View original

71–80 of 189 posts

Re: Density.io

#71

Post by MAGZine »

aroch wrote: post #20
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.

Network's that whitelist devices by MAC and device registration/provisioning by MAC. And debugging network is theoretically easier when every device has a unique MAC. There are several applications for OSX and various *nix distros that run at boot and randomize MACs. SpoofMac is probably the most well known: https://github.com/feross/SpoofMAC

This is perfect--I'm definitely going to set this up.

I'd just like a background service for my Android device that would also randomize my MAC address... (perhaps it's time to investigate android development :P)

Re: Density.io

#72

Post by samstave »

porker wrote: post #47
buro9 wrote: post #42

Earlier quoted context omitted.

Have you seen the Off Pocket? https://offpocket.com/ Though in the UK I have unlimited 4G for £20 per month, so I just leave WiFi permanently disabled.

Is Off Pocket any different to putting your phone in airplane mode every time you put it in your pocket? It's certainly more convenient, but also harder on the battery life as the phone continues to search for a signal.

Need an off pcket with an NFC tag in it that shuts the phone down whilst in proximity. When the tag goes away, the radios awaken...

Re: Density.io

#73

Post by deutronium »

Interesting idea, but wouldn't you get better coverage of people using GSM addresses, rather than Wifi MAC addresses?

Also it could be rather easily tricked by competitors, by constantly switching the MAC address.

Re: Density.io

#75

Post by kej »

Sprint wrote: post #61

Time to build a device that pollutes the databases with useless data.

No need to build anything, just use an existing device that can change its wifi MAC address.

Re: Density.io

#77

Post by Robin_Message »

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?

That seems like it would work, but it turns into a "open using crowbar found inside" problem: how do I know to use the same salt on a second density.io device unless I have already matched the MAC address.

Re: Density.io

#78

Post by shiftpgdn »

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…

City of Houston does MAC address tracking on the freeways and surface streets to power their traffic tracking measures. It's probably used in hundreds of other places you haven't thought about. If you're concerned about your privacy just turn wifi off.

http://traffic.houstontranstar.org/layers/

Re: Density.io

#79

Post by ynniv »

I hadn't realized how trackable cell phones were until I was experimenting on a wifi project and saw both MAC addresses and Preferred Network List of devices within the area that had not joined my network. Cell phone wifi is a privacy nightmare. Even the most technical people don't realize this, so projects that popularize it are going to kick up huge amounts of mud. Think of how easy it is to identify "whale" clients, if not by direct tracking, then by revenue correlation (these N people were present for $N,NNN,NNN in revenue events). They're valuable to track because when they show up you want your sales people to be at their best, but a service that starts tracking those people is going to make real enemies quickly.

Re: Density.io

#80

Post by yread »

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…

You could salt the hash with a constant secret
Post reply on HN