00000ctmaa22000003a 4500 UP-1685675941123922702 Buklod 20150608094313.0 aa rb |||1 u| ta 150608s xx d r |||| u| (iLib)UPTAC-00017445482 DENGII eng LG 995 C65 U48 2013 Ultra, John D. author A collaborative access control model for e-voting systems John D. Ultra. 2013. vii, 62 leaves. Thesis (M.S. Computer Science)--University of the Philippines, Diliman. Available to the general public. We observed that distributing trust or authority, also known as Separation of Duty (SoD), is a common strategy in cryptographic voting schemes to increase the integrity and availability of its components. However, such schemes only cover a subset of the administrative activities performed in an election e.g. voter registration, voting and votes tallying. In order to maintain the overall operational integrity of an election, it is also a good idea to employ such strategy to other election administrative tasks not covered by the cryptographic voting scheme implemented on an e-voting system. To this end, we proposed a collaborative access control model which can be used for enforcing SoD on other election administrative tasks which are performed through an e-voting system. Our model offers a novel approach for modeling SoD policies which has the ability to reduced the set of conflicting permissions which needs to be managed explicitly in the system which makes the administration of the access control system easier. It also natively enforces SoD dynamically. Moreover, our model also allows dynamic definition of the SoD policy of a task i.e. during the application's run time. This means that in an e-voting which hosts multiple elections at a time, it is possible to define SoD policies on tasks per election basis. Aside from enforcing SoD on tasks, our model also provides an auditing mechanism, called integrity verification, which could be used by election auditors in verifying the integrity of data objects contained in an election e.g. election, ballot, and voter data objects. More concretely, we described an implementation of our model on the Helios we-based voting application. The user study we performed on the implementation of the access control model on Helios showed positive insights about the practical usability of the model when used in a real application. Helios (Computer file). Electronic voting Access control. Separation of Duty (SoD). FI UP UPTAC UPTAC LG 995 C65 U48 2013 Thesis