Anonymization is the biggest privacy threat no one talks about

13 Ground Floor Apartment Privacy I...
13 Ground Floor Apartment Privacy Ideas

ivan_kislitsin /

Are you really anonymous on the Internet? Despite your best efforts, artificial intelligence and ever-present surveillance systems around you could reveal your identity and activities to anyone who has access to that “anonymized” data in a practice known as “de-anonymization.”

Your data is valuable

Most of the services you enjoy but don’t pay for directly on the Internet make money by collecting and selling data. That data includes everything you do on the Internet, tracked by third-party cookies across multiple sites. Other types of data can also be collected, such as location data, and it doesn’t stop there. All the detailed information about how you interact with digital systems can be recorded and analyzed.

This data is “anonymised,” which simply means that information that directly identifies you has been removed. That is things like your name, IP address, physical address, and anything similar. What remains is everything else, which can be used to create detailed profiles connected to an advertising ID.

Re-identification is becoming trivial

A single red wooden figurine separated from other wooden figurines.
Andrii Yalanskyi /

The problem with this anonymization process is that it is becoming trivial to re-identify anonymized data by matching it against publicly available information or against information collected from multiple websites using the aforementioned tracking cookies.

There is an entire data brokerage industry that has sprung up around the creation of these marketing profiles that can be sold to anyone willing to pay for them. Data brokers were brilliantly explained by John Oliver in an episode of last week tonight.

Imagine having a phone book that, in addition to your name, address, and phone number, also tells people about your income, health issues, stage of life, and more. Reidentification is so easy that the researchers estimate that “99.98% of Americans would be correctly reidentified in any data set using 15 demographic attributes.”

Deanonymization and Cryptocurrency

In addition to the run-of-the-mill data collection that happens every day, there is a special kind of anonymization concern tied to blockchain technologies such as cryptocurrencies. A blockchain ledger keeps a perfect record of every transaction that has occurred since the blockchain was created.

Crypto wallets are just collections of numbers without names. and this has led to the belief that cryptocurrency is anonymous. The problem is that transactions on the blockchain can be matched against third party data removing you from anonymity. That can include when you exchange cryptocurrency for dollars, when a product you have purchased with cryptocurrency is shipped to your home, or anything else where the activity or amounts reflected on the blockchain match something that is not anonymous.

This is why cryptocurrency mixers and cups exist, which perform random transactions and mix coins in participating wallets, obscuring the trail. Some cryptocurrencies, like Monero, are designed from the ground up to combat this problem.

However, even if you are using a strong anonymous currency today, future computer technology can easily crack the blockchain, which is indelible. So something you did decades before that point could be discovered in the future, and if it’s already on the blockchain, there’s nothing you can do about it!

What can you do?

The first and most effective thing you can do is change the type of software you use to search or browse the Internet. There are engines (eg DuckDuckGo) and browsers (eg Brave) that specifically block tracking cookies and other tracking methods to prevent data collection.

Apple has a policy that apps have to ask if they can track you or not. For a general solution, you can go to Privacy > Tracking on your iOS device and disable Allow apps to request tracking.

The only really negative thing for you as a user is that you will now see random ads that may be irrelevant to you, but that’s a small price to pay for privacy.

You can also be selective about when and how you block tracking. Limit it to the things you definitely don’t want people to know about you, but be more forgiving of the facts you don’t care about. For example, you can ask apps on iOS not to track on a case-by-case basis, depending on how sensitive you think the information is. You can also use a privacy browser (within a virtual machine, over the Tor network, and with a VPN if you’re Really in question) only for sensitive navigation. Thus segmenting your online life into public and private spheres.

If you’re really worried about your smartphone or other devices giving away your presence in sensitive places, you also have the option of using a Faraday bag, which will temporarily block all radio signals from your phone until you take it out.

As for the information that has already been collected, that is a more difficult issue. A lot depends on where you live. In Europe, for example, the GDPR legal framework gives citizens resources and a “right to be forgotten”, but in the US this is not the case. The most practical thing you can do is control and limit future tracking, until existing information about you becomes worthless.