Measures to minimise internet
tracking
September 2020

Introduction
When using The Internet, certain practices affect yourprivacy - such as browsing activity tracking on manywebsites. This is usually done through cookies - mainly
advertising or analytics cookies. Their aim is to create
profiles with a view to offering advertising that aligns
with the interests and specific characteristics of each
person. They are also used for collecting statisticalinformation about accessing online services.
When you visit a website, you are not just accessing
one single webpage. You are also redirected in parallel
to multiple third-party servers that generally provide
advertising and data analysis services for the main
website. Giving these third parties access is whatallows them to install and access information linked tothe cookies1 that track the activities of each user. This
is why most techniques used to improve user control
over internet tracking are based on the option ofminimising third-party cookies, or directly preventing
access to those third parties.
Although it is the best-known method, it is not justcookies that are used to track someone as they browse
online. Other techniques are used to achieve the samepurpose, including those based on unique advertisingidentifiers2, or those implemented by obtaining thedevice fingerprint3. In browsers, Local Storage andIndexedDB also allow information on the device to be
stored and retrieved while browsing, and can also be

used for tracking user activity. Server logs (whichrecord activity) can also be exploited in this way bycorrelating information stored on various sites.
Therefore, preventing access to services that do thiswithout offering appropriate guarantees is the mosteffective method of protecting your privacy.
Please keep in mind that these user-tracking
techniques are not unique to browsers on personal
computers. Mobile phones, tablets and other smart
devices, such as Smart TVs, also use unique advertisingidentifiers. These identifiers are sent to internet
servers when an app is used and when certain eventsoccur, allowing the user to be identified and tracked.
Something else to keep in mind is that web browsers
and devices also allow you to log in, for example, with
an email account. This allows direct access to email
and many other applications directly from the browser
interface and options, as well as maintaining options
for personalising services. Once the user session isstarted, the browsing history can be automatically sent
to the provider of that service.
It is also possible to track user activity throughfederated authentication services offered by large
internet and social network companies. This happens
when you can use your Facebook, Google or otheraccounts to sign in a particular website or application.

1 Guide to the use of cookies. AEPD.
2 Technical note: User control when customising Android advertisements. AEPD.
3 Device fingerprinting study. AEPD.

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Measures to minimise internet tracking

www.aepd.es

Basic recommendations
The following are basic recommendations for users
without advanced knowledge to minimise unwanted
exposure of personal data:

1.Consider privacy to be a desirable feature whenchoosing a browser and any applications you installand use on your devices. Due to the way these products
are constantly evolving you should check the mostrecent analyses published about them.

2.Avoid installing unnecessary applications on yourbrowser, as this will minimise risks.

3.Keep your browser up to date with the latest
tracking protection technologies.

4.If your browser has advanced tracking protection ,4

7.Another option when browsing sites that require

greater access to your data is to add an exception inyour browser settings, but remember that you will be
exposing personal information with the sites includedin the exception.

8.You can set the browser so that cookies are deleted

when you close it. If this does not suit you whenbrowsing your favourite sites, you can choose to delete
the cookies manually every so often.

9.Prevent to log in to the browser if you can,identifying yourself with a user, or at least, avoid
keeping the session open indefinitely. Also, set thebrowser so that it does not synchronise your browsing
data with your session user.

activate it and keep it on. These options allow forvarious levels of protection. Choose the highest level tosuit your preferences. In any case, you can if you wish
enable the option to send a "Do not track" 5 signal towebsites.

10.If the browser does not have advanced tracking

5.If you wish, you can set your browser to block third-

11.You can, if you wish, set your device options soparty cookies6, or at least block them when you browse
in private mode. In browsers with antitracking/tracking protection, these options will beintegrated under the settings.

6.Consider having two different browsers: one withmore restrictive setting; the other, configured withhigher permissions. This means that if the browser
with more restrictive settings prevents you fromaccessing a particular service, you can use the otherbrowser to access that service, thus minimising theexposure of your data.

4 Tracking protection on Mozilla Firefox and Microsoft Edge.
5 "Do Not Track" signal settings on Chrome, Firefox and Edge.
6 Third-party cookie blocking on Chrome, Firefox and Edge.
7 Changing/resetting the advertising identifier in Android and iOS.
8 Advertisement personalisation control for Twitter, Facebook and Google.

2protection, you can install extensions to do this.
However, only install extensions that offer guarantees.
In general, installing third-party software on top ofyour browser can introduce risks.

that the advertising identifier is not used to create
profiles or display tailored advertisements based onyour location or profile. If your device allows, you canalso change7 the advertising identifier every so often
under privacy settings.

12.Review and configure customisation, profile andadvertising options for any applications, services andsocial networks8 you use.

Measures to minimise internet tracking

www.aepd.es

Recommendations for advanced users
Advanced techniques can be used to achieve ahigher level of control and protection against
unwanted monitoring on The Internet - including:

1.Setting up a DNS query blocker - such as PiHole 9on your home network. This allows you to add lists ofdomains that connections from devices on yournetwork are restricted.

2.Browse via a VPN (virtual private network) or theTOR10 network. Keep in mind that using these services
inappropriately can pose other risks to privacy andsecurity in your connections.

3.Install virtual machines on your system, including
just a web browser and browse under virtual sessions.

4.Use operating systems that are designed topreserve privacy and anonymity, such as Tails11 andQubesOS12.

9 https://pi-hole.net/
10 https://www.torproject.org/es/
11 https://tails.boum.org/install/
12 https://www.qubes-os.org/intro/3