Mr. Jorba's effort---- ---------- Dear all, I have successfully completed a doctorate in Computer Science. My research work has focused in secure large scale voting schemes. The PhD Thesis is entitled "Design of implementable solutions for large scale electronic voting schemes". The Thesis can be downloaded from my homepage at http://ccd.uab.es/~andreu/indexenglish.shtml both as a PostScript file (3 MBytes) and a gziped PostScript file (400 Kbytes). Next, I include the abstract of the Thesis to allow a quick look at its contents. ABSTRACT: The aim of an electronic voting scheme is to conduct secure elections over general-purpose and open computer networks. To achieve security in such an unsecure environment, the voting system has to be designed by accurately combining a number of cryptographic tools and protocols. In this thesis, we propose practical solutions to the currently most serious open problems concerning the design of secure voting schemes, in particular when large numbers of voters are involved. All these solutions are mainly devised to allow an easy implementation. In order to perform large scale electronic elections, a number of distributed electronic electoral colleges have to be operated concurrently. This creates the need for a set of coordination mechanisms and protocols. In this thesis, we define various types of voting authorities, each one of these with a differentiate role, and we propose a hierarchical model that links them and that efficiently solves the coordination problems. We offer a practical solution to the implementation of a large and distributed electoral roll. To achieve anonymity in the election, we use the mobile agents paradigm to mix ballot boxes at the tallying phase, when all (enveloped) ballots are already cast. This approach avoids the usual and (from the practical point of view) annoying use of anonymous channels to cast the ballots. In addition, we offer mechanisms to assure the accuracy of the tally and to prevent the publication of intermediate results before the election is completed. Electronic elections are specially prone to suffer from coercion because voters usually have the ability to prove their respective voting strategies. In this thesis, we propose a technique to prevent massive coercion in large scale voting schemes. Our solution is based on the use of tamper-proof smartcards by voters. The main advantage over previous proposals is that we do not restrict the mobility of voters. Finally, in this thesis we improve previous methods of allowing open (public) objection to the tally if some inaccuracies are detected when the election results are published. The classical vote-tag model is normally used to achieve this goal. However, its implementation leads to ballot casting protocols inconvenient for voters. We offer an efficient alternative to construct vote-tags, improving the computation costs of previous proposals. This makes our solution the first implementable method to allow open objection to the tally. Andreu ----------------------------------------------------------- Andreu Riera Jorba Dept. Informātica Universitat Autōnoma de Barcelona 08193 BELLATERRA (BCN) Catalonia - Spain Phone# +34 93 581 1777 Fax# +34 93 581 3033 E-mail [EMAIL PROTECTED] WWW http://ccd.uab.es/~andreu ====================================================================== This message was distributed through the e-lection mailing list. For info and archives see http://www.research.att.com/~lorrie/voting/ ======================================================================