arXiv subjects

Ana Sokolova

Publications and source records attributed to Ana Sokolova.

21 records · Page 2Linked to original sources

arXiv2012

Proceedings Fifth Interaction and Concurrency Experience

This volume contains the proceedings of ICE'12, the 5th Interaction and Concurrency Experience workshop, which was held in Stockholm, Sweden on the 16th of June 2012 as a satellite event of DisCoTec'12. The topic of ICE'12 was Distributed Coordination, Execution Models, and Resilient Interaction. The ICE procedure for paper selection allows for PC members to interact, anonymously, with authors. During the review phase, each submitted paper is published on a Wiki and associated with a discussion forum whose access is restricted to the authors and to all the PC members not declaring a conflict of interests. The PC members post comments and questions that the authors reply to. Each paper was reviewed by four PC members, and altogether 8 papers were accepted for publication. We were proud to host two invited talks, Marcello Bonsangue and Ichiro Hasuo, whose abstracts are included in this volume together with the regular papers.

cs.PL↗

arXiv2007

Generic Trace Semantics via Coinduction

Trace semantics has been defined for various kinds of state-based systems, notably with different forms of branching such as non-determinism vs. probability. In this paper we claim to identify one underlying mathematical structure behind these "trace semantics," namely coinduction in a Kleisli category. This claim is based on our technical result that, under a suitably order-enriched setting, a final coalgebra in a Kleisli category is given by an initial algebra in the category Sets. Formerly the theory of coalgebras has been employed mostly in Sets where coinduction yields a finer process semantics of bisimilarity. Therefore this paper extends the application field of coalgebras, providing a new instance of the principle "process semantics via coinduction."

cs.LO↗

arXiv2007

Probabilistic Anonymity and Admissible Schedulers

When studying safety properties of (formal) protocol models, it is customary to view the scheduler as an adversary: an entity trying to falsify the safety property. We show that in the context of security protocols, and in particular of anonymizing protocols, this gives the adversary too much power; for instance, the contents of encrypted messages and internal computations by the parties should be considered invisible to the adversary. We restrict the class of schedulers to a class of admissible schedulers which better model adversarial behaviour. These admissible schedulers base their decision solely on the past behaviour of the system that is visible to the adversary. Using this, we propose a definition of anonymity: for all admissible schedulers the identity of the users and the observations of the adversary are independent stochastic variables. We also develop a proof technique for typical cases that can be used to proof anonymity: a system is anonymous if it is possible to `exchange' the behaviour of two users without the adversary `noticing'.

cs.CR↗