SSL (Secure Socket Layer) is a protocol for secure transmission of data over the Internet. SSL encrypts all data which is sent between the web browser and the web server, and by using digital keys you make sure that the data arrives safely to the recipient.
Researchers and others employed at the University of Oslo in some cases participate in international projects using x509 certificates for authenticating users and giving access to web-sites or services in connection to the projects. This page gives a short explanation of what x509 certificates are and how you can obtain one if needed.
This document describes giving UiO users rights to request x509 certificates through Digicert portal. It is intended for the persons who have been delegated certificate administrators privileges. For x509 user documentation take a look here.