09031 Abstracts Collection - Symmetric Cryptography.

From 11.01.09 to 16.01.09, the Seminar 09031 in ``Symmetric Cryptography '' was held in Schloss Dagstuhl~--~Leibniz Center for Informatics. During the seminar, several participants presented their current research, and ongoing work and open problems were discussed. Abstracts of the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section describes the seminar topics and goals in general. Links to extended abstracts or full papers are provided, if available.