# Digital Identity in the EU: Promoting eIDAS Solutions Based on Biometrics
## 2 From Personal Identity to Digital Identity  
With the rise of the Digital Society, the legal framework of privacy regulation is being enriched with a new notion, \"digital identity\", which has now become part of the vocabulary of jurists and legislators around the world. Commonly, it is declined in two distinct ways; according to the first and broader meaning, the expression is used as a synonym for \"networked\" or \"virtual\" identity. Frequent is its use within the legal and sociological debate [15] regarding the possibility of \"fake identities\" online [16] (e.g., names and personal information different from those used in real life) or the use of \"vague identities\" (pseudonyms or nicknames). On the contrary, according to a narrower meaning, typically attributable to specialists in computer law, the expression digital identity is defined as \"the set of information and resources granted by a computer system to a particular user of said system\" [17]. Obviously, said information is usually protected by an authentication system based on passwords,additional devices (magnetic card, smart card, etc. ), or biological traits (iris, fingerprint, face, etc.). The latter meaning of digital identity is commonly referred to in the now substantial literature on the subject of \"identity theft\" [18]; in fact, it already emerges clearly how any discourse on digital identity must necessarily touch two aspects, namely the protection of personal identity on the Web, which we have already argued about previously, and the techniques of subject authentication by means of computer tools, which we will discuss next. To better explain this aspect, we start by noting that the terms \"authentication\" or \"identity verification\" generically refer to the process needed to ascertain the identity of an individual, both physically (for example, in the case of an airport police checkpoint) or remotely; in the latter case, when the process is essentially automated by computer tools, the terms \"electronic identification\" (eID) is commonly adopted. It is also worth noting that personal data (which define personal identity) can include a very diverse range of information: these data can uniquely distinguish a person in business practices (e.g., name, date and city of birth, identification number, social security code) or be part of a more intimate set of personal traits that uniquely represent a human being (e.g., fingerprints, iris prints, photographs) or that relate to his or her cultural or social identity (e.g., gender, ethnic group, nationality, religion). Not all these data are significant for transactions, nor to ascertain the identity of the individual; moreover, not all these data must be necessarily stored on a computer or be part of a computer representation. What matters, in this perspective, is the viability of a technological solution for reliably establishing the identity of a natural or legal person in the context of a digital transaction through an electronic identification process that we will also better denote as a \"digital identity scheme for the transaction\" [19]. Please refer to the next section for a more detailed discussion of this concept. Digital Identity Schemes for Transactions  
Electronic identification is the gateway to many public and private services; among these, it is strictly required for private services (bank accounts, insurance, car rental, hotel booking), government services (certificates, taxes, driving license), education (enrollment, exams), and access to medical treatments or data. However, note that rarely do these services rely on a common digital identity scheme. Most of the time, public providers act like commercial providers (e.g., social media or shopping online), issuing credentials, adopting proprietary access schemes, and storing data independently [20]. This attitude has been recognized as the main cause of an exponential increase in account numbers and privacy breaches. As illustrated in Figure 1, actual digital identity schemes are based on two distinct phases:  
1.