The project "Authentication of Mobile Nodes and Mobile Code" ran between 2000-2002. This is the final report with a short summary and conclusions of the project. The project has focused on authentication in three areas - authentication in network based systems, mutual user and systems authentication and mobile code respectively. These have been viewed from a set of demands given by the vision of the network based defense. We have studied three methods for authentication in network based systems - ticket based, certificate based and identity based methods respectively. Most flexible are certificate methods. Identity based methods can only be used in local groups. A model is presented for mutual user and systems authentication. It is further developed in another project. Different types of mobile code have been studied. Mobile agents are not yet ready for use. Mobile code for control of active networks is more likely. We have identified both pros and cons for security.