438 Formalization and analysis of Borda protocol using pi calculus Bhakti S.Kurhade Stdt.Computer Science and Engg dept. Yashwantrao Chavan College Of Engg , Nagpur, India Dr. Manali Kshirsagar Dean student activities Yashwantrao Chavan College Of Engg Nagpur, India Abstract— The constant development in computer technology now gives rise to an efficient way of using computer or electronic medium of voting. Electronic voting ensures the possibility of efficient, convenient and secure facility for recording and tallying votes in an election. The applied pi calculus is a language for describing concurrent processes and their intersections. The applied pi calculus is a way, to formalize such protocols, and helps us to verify properties by using automatic tools, and to trust on manual proof techniques because sometimes automatic tool cannot handle some cases. We model a known protocol BORDA which is a e voting protocol , in the applied pi calculus, and we formalize some of its expected properties. We use the ProVerif tool to verify the properties. Sometimes Proverif is unable to prove any of the property, because its ability to prove observational equivalence between processes is not complete. Keywords- Borda voting protocol, Electronic voting, security, privacy protection, Fairness , universal verification Introduction Voting is concurrently shifting from manual paper based processing to automated electronic-based processing votes based on greater efficiency, faster speed ,better scalability, low cost and more vulnerabilities. Variety of types of elections from small committee’s or online committees are done through electronic voting system but after analysis it found some possible attacks based on formal protocols ,a much more secure system could be implemented to specify the message sent between the voters and the administers. In electronic voting, there are two main kinds of schemes. First is a blind signature scheme in which the voter first gets a token in the form of a message. This message is blindly signed by the administrator and the voter himself. They send the message anonymously. This token is a proof of eligibility .Voter joins the administrator to construct an encryption o his vote by homomorphic encryption. Following are the properties which electronic voting protocols may satisfy: Eligibility: Voters who have registered can vote, and only once. Privacy: there should no way to relate voter and his vote. Individual verifiability: a voter can verify that his vote is really counted or not. Universal verifiability: obtained and published result is the total of all votes Fairness: no early results can be obtained which could influence the remaining voters.. Receipt-freeness: there should be no way to prove the voter has voted by certain way. In this paper, we study a protocol known as the BORDA scheme [12],our focus is on informal analysis, our protocol must satisfy above properties which are essential for secure electronic voting system . Formal verification techniques are particularly important because security protocols are notoriously difficult to design and analyze. In several cases, by means of formal verification techniques protocols which were thought to be correct for several years have, been discovered to have major flaws [14, 6]. In this paper our aim is to use verification techniques to analyze the BORDA protocol. In the applied pi calculus [3],we model this protocol. Many proof techniques are available in applied pi calculus which we can use, is supported by the ProVerif tool [4], and this has been used to analyze a variety of security protocols. I. THE BORDA PROTOCOL In this section, we first present the Borda voting protocol briefly, and then consider the security issues related. 2.1 Voting mechanism Voting depends on a social choice function. There are infinite number of votes and these infinite votes are given as input to the function. The output obtained is the result of choices given by voters and ranked according to voters preferences. Borda voting method is proposed by the French mathematician Jean Chales de Borda some 200 years ago for the improvement over the plurality protocol. In the borda protocol preferences are given to us and we rank these preferences assigning them different points. The result get displayed with highly voted candidate with n votes is on the top second placed candidate with n-1 votes and so on.