Data Anonymization  What is it? + How It Works ▷ 2020

For protect personal data it is necessary to comply with a process, known as anonymization. It is true that this word, according to RAE, does not exist. But in the world of computing is essential for information privacy.

In this article, you will find all the information related to this topic. Including the meaning of anonymization with an easy-to-understand concept, and without so many legal points.

We will also explain what is the importance of this process, and the phases that you must complete to avoid disclosure of confidential information. With our informative article, you will be able to instruct yourself in a professional way, on the subject of privacy of personal data.

What is anonymization and what is its importance in today’s Internet?


Anonymization is the process that consists of storing information or personal data, without being identified. This process is irreversible, and is based on the RGPD (General Data Protection Regulation) of the European Union.

Thanks to anonymization, the data is protected 90% hiding the corresponding identifiers, protecting the privacy of the sender. However, 100% anonymous status cannot be maintained, due to the traces left on the networks, or transmission routes. This every day becomes a greater requirement, when there are massive processing of personal data, so that, when receiving information theft attacks, it is not seen compromised the integrity of any stakeholder.

Principles of data anonymization What are they and what are they based on?

Establishing an anonymization process consists of different beginning, that we must take into account before starting it.

Next, we will show you and explain what each one consists of:


Protection of data confidentiality, should always be done proactively, and never reactive, with the intention of guaranteeing greater protection of information. This is done from the design of the information system.

Privacy by default

If we design an information system, it is mandatory that we guarantee the protection of the confidentiality of those involved. The objective of this principle, it is focused to establish by default an anonymization of data.

Objective privacy

In any anonymization process, residual traces of user identifications are left, but this should not be assumed by who receives the information, but rather by who transmits it.

Full functionality

In the processes of anonymization, different details must be taken into account, including the final disposal of anonymized data, so that the distortion of information is prevented, ensuring a highly secure transfer and usefulness of data.

Privacy in the information life cycle

There are data that are not useful for the process, which are suspended in the transmission networks. These must be removed, to avoid distortion or theft of information. It is an essential foundation for data privacy, either by transmission from emails, or web pages.

Information and training

People who are involved in the anonymization process must be previously informed and trained about their obligations, and responsibilities of each of the parties. Correct training of all parties on this subject is essential.

Pseudonymization and anonymization How are both concepts different?

Anonymization vs sedonimizationb

Previously we knew a brief concept of anonymization, now we will understand what pseudonymization means. Understanding both terms is necessary, before finding their differences. Pseudonymization, is the process that consists within the framework of the GDPR as a technique for identifying personal data, with nicknames or pseudonyms. This must be done for each data set, the intention is that only specific people know who the information is, when viewing the artificial identifier granted.

We can say that it is the process that consists of the elimination of an identifier for personal data, this must be done irreversibly, to maintain confidentiality. While pseudonymisation consists of the identification by means of artificial names. With anonymization, people lose absolute relation to the data they share, while the objective of pseudonymisation is allow a relationship to be maintained by means of a code or pseudonym.

What are the most important steps to be 100% anonymous?

To be 100% anonymous, or as close to this percentage as possible, we must take into account some phases that we must fulfill.

Next, we will explain what each of these phases consists of:

Definition of the work team

It is extremely essential selection of work team, and this is influenced by changes in roles and profiles for each of the people. It is recommended that, in this phase of recruitment and assignment of permits, everyone is very clear about their work to develop.

Risk analysis

Thorough inspections and analyzes should be performed on possible risks that exist in the process of anonymization, since it is a fundamental basis to be able to establish a security system with adequate force. In this same phase, it should be emphasized regarding the guarantee of the impossibility of identifying the anonymized data, since there will always be a small percentage of probability that allows it.

Definition of objectives

The anonymization process must be conditioned from its design, with the aim of protect anonymized data. That is, protect all the information contained in the database, restricting access to profiles without permissions.

Process feasibility

Based on the AEPD (Spanish Agency for Data Protection), the analysis of the entire anonymization process is essential, so that its viability can be verified.


This is the process that runs before anonymization, and consists of evaluating all the possibilities, direct or indirect, for the re-identification of personal data, with the intention of developing a sufficient protection system so that data privacy is maintained.

Variable reduction

In this phase, the access of the personnel to the editing or manipulation of the stored data must be completely or as much restricted as possible, so that the variables that are related with the spread of it. It affects optimizing the process by means of computational algorithms, for the operations and management of personal data.

Selection of anonymization techniques

This phase indicates compliance with the recommendations of the techniques, made by the AEPD:

  • Algorithms by HASH
  • Algorithms encryption
  • Stamp of time
  • Cap anonymization
  • Disturbance of data
  • Reduction of data

Information segregation

So that they can be enhanced separate treatments of the personal data stored, system maps must be prepared, so that it is established a specific process for each.

Pilot project

The development of a pilot project is extremely important, because it is through it, where the feasibility of the personal data security and anonymization system will be studied. It should be done with non-real data, in order to check the entire process. If some faults are found, the process must be re-established, since the objective is to leave the minimum probabilities of a data re-identification.


In the last phase, you must perform a segregation of all data, so that the anonymization process is completely irreversible. This phase must be carried out as many times as necessary, depending on the needs and objectives set by the recipient.

Main methods to be anonymous What are the most efficient techniques?

In this last section of this article, we will explain to you what are the different techniques that are established for anonymization:

Mask the data

This technique does reference to partial deletion of data so that it cannot be identified at first glance. In other words, those identifiers should be removed essentials, such as names, and addresses. Data masking, It has two variants.

Such are the following:

  • Partial removal: refers to the elimination of data such as name, contact numbers, dates of birth, or physical addresses.
  • Data quarantine: it is the partial elimination of the information, or the exclusion of people from accessing confidential information.


As we have already explained, pseudonymisation is about remove and replace the identification of data, by a pseudonym, so that can only be identified by specific people.


The aggregation consists in the sample of a data set, without each of them being identified. In this process, data that have the same recipient are collected, with others whose authors are not the same.

Data elements and derivatives

This technique is used to suppress essential information, for the re-identification of personal data. It consists of hiding exact values of the information, for this, dates of birth are replaced with ages, names with nicknames, among others.

If you have any questions, leave them in the comments, we will answer you as soon as possible, and it will also be of great help to more members of the community. Thank you! 😉

You may be interested:

Leave a Comment