This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.
This is the author's version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution.
The copyright for this work is held by Springer and the original work is available at http://www.springer.de.
Copyright and Reprint Permissions: The Internet Society owns the copyrights for this paper. You may freely reproduce all or part of any paper for noncommercial purposes if you credit the author(s), provide notice to the Internet Society, and cite the Internet Society as the copyright owner. Reproduction for commercial purposes is strictly prohibited without the prior written consent of the Internet Society, the first-named author (for reproduction of an entire paper only), and the author's employer if the paper was prepared within the scope of employment. Address your correspondence to: Manager of Conferences, Internet Society, 1775 Wiehle Ave., Suite 102, Reston, Virginia 20190, U.S.A., tel. +1 703 326 9880, fax +1 703 326 9881, email@example.com.
Copyright © Lujo Bauer