This book constitutes the refereed proceedings of the 16th International Conference on Secure IT Systems, NordSec 2011, held in Tallinn, Estonia, October 26-28, 2011. The 16 revised papers presented together with 2 invited talks were carefully reviewed and selected from 51 submissions. The papers are organized in topical sections on applied cryptography, commercial security policies and their enforcement, communication and network security, security modeling and metrics, economics, law and social aspects of security, and software security and malware.

We generate and gather a lot of data about ourselves and others, some of it highly confidential. The collection, storage and use of this data is strictly regulated by laws, but restricting the use of data often limits the benefits which could be obtained from its analysis. Secure multi-party computation SMC, a cryptographic technology, makes it possible to execute specific programs on confidential data while ensuring that no other sensitive information from the data is leaked. SMC has been the subject of academic study for more than 30 years, but first attempts to use it for actual...