The “restricted identification” process is used for the pseudonym function. It can be employed to generate pseudonyms for a specific chip and a specific online service.

The pseudonym is generated by the chip contained in the national identity card using a public key contained in the service provider’s authorisation certificate and a private key that is saved on the identity card. It is then transmitted to the service provider.

Using the pseudonym, the service provider can associate the user with the correct account the next time the user logs in. When the pseudonym alone is used, no further information concerning the user, such as their name or address, is passed on to the service provider.

As difference pseudonyms are generated from the national identity card for the different online services, no cross-provider user profile can be created. This considerably increases the data privacy level of the online identification process.