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Abstract Through the broad usage of cloud computing and the extensive utilization of next-generation public clouds, people can share valuable information worldwide via a wireless medium. Public cloud computing is used in various domains where thousands of applications are connected and generate numerous amounts of data stored on the cloud servers via an open network channel. However, open transmission is vulnerable to several threats, and its security and privacy are still a big challenge. Some proposed security solutions for protecting next-generation public cloud environments are in the literature. However, these methods may not be suitable for a wide range of applications in a next-generation public cloud environment due to their high computing and communication overheads because if security protocol is strengthened, it inversely impacts performance and vice versa. Furthermore, these security frameworks are vulnerable to several attacks, such as replay, denial-of-service (DoS), insider, server spoofing, and masquerade, and also lack strong user anonymity and privacy protection for the end user. Therefore, this study aims to design an elliptic curve cryptographic (ECC) based data access control protocol for a public cloud environment. The security mechanism of the proposed protocol can be verified using BAN (Burrows-Abadi-Needham) logic and ProVerif 2.03, as well as informally using assumptions and pragmatic illustration. In contrast, in the performance analysis section, we have considered the parameters such as the complexity of storage overheads, communication, and computation time. As per the numerical results obtained in the performance analysis section, the proposed protocol is lightweight, robust, and easily implemented in a practical next-generation cloud computing environment.

Through the broad usage of cloud computing and the extensive utilization of next-generation public clouds, people can share valuable information worldwide via a wireless medium. Public cloud computing is used in various domains where thousands of applications are connected and generate numerous amounts of data stored on the cloud servers via an open network channel. However, open transmission is vulnerable to several threats, and its security and privacy are still a big challenge. Some proposed security solutions for protecting next-generation public cloud environments are in the literature. However, these methods may not be suitable for a wide range of applications in a next-generation public cloud environment due to their high computing and communication overheads because if security protocol is strengthened, it inversely impacts performance and vice versa. Furthermore, these security frameworks are vulnerable to several attacks, such as replay, denial-of-service (DoS), insider, server spoofing, and masquerade, and also lack strong user anonymity and privacy protection for the end user. Therefore, this study aims to design an elliptic curve cryptographic (ECC) based data access control protocol for a public cloud environment. The security mechanism of the proposed protocol can be verified using BAN (Burrows-Abadi-Needham) logic and ProVerif 2.03, as well as informally using assumptions and pragmatic illustration. In contrast, in the performance analysis section, we have considered the parameters such as the complexity of storage overheads, communication, and computation time. As per the numerical results obtained in the performance analysis section, the proposed protocol is lightweight, robust, and easily implemented in a practical next-generation cloud computing environment. [ABSTRACT FROM AUTHOR]

Type systems as a technique to analyse or control programs have been extensively studied for functional programming languages. In particular, some systems allow one to extract from a typing derivation a complexity bound on the program. We explore how to extend such results to parallel complexity in the setting of pi-calculus, considered as a communication-based model for parallel computation. Two notions of time complexity are given: the total computation time without parallelism (the work) and the computation time under maximal parallelism (the span). We define operational semantics to capture those two notions and present two type systems from which one can extract a complexity bound on a process. The type systems are inspired both by sized types and by input/output types, with additional temporal information about communications. [ABSTRACT FROM AUTHOR]

This paper deals with modeling and verification of software systems by combining UML diagrams and Pi-calculus. UML 2.0 Activity diagrams are used for modeling the behavior of software systems, while Pi-calculus is used for semantic and verification purposes. More precisely, UML is a semi-formal language and so it needs formal semantics for its constructs and lacks tools for verifying properties. To this end, we propose an approach and a tool called AD2PICALC for transforming UML 2.0 Activity diagrams to Pi-calculus processes using Eclipse Xpand and TGG tools. The obtained Pi-calculus processes are then used as input for Pi-calculus tools, like MWB, to verify some properties as deadlocks, safety, determinism, termination and livelock. We illustrate our contribution through an example from the literature and verify the property of deadlock using MWB tool. The main contribution of this paper lies in the automation of the transformation approach using TGG tools.

Investigates the definition of behavioral equivalence for parametric polymorphic processes. Discussion on the syntax, typing rules and operational semantics of polymorphic pi-calculus; Definition of barbed bisimulation for polymorphic processes; Interactions between polymorphism and aliasing.

Security protocols are very important in every communication over the Internet. They aim to deliver safe services by ensuring authentication, confidentiality and integrity of the data transiting in the network. So, each new proposed security protocol should be tested and formally verified to be sure of security features since deploying new protocols without analyzing their security properties could causes bad impact on sensitive data. In this paper, we present a formal model for the verification of the E-DNSSEC protocol which is proposed to add confidentiality property to the DNSSEC protocol. For that purpose, the article provides first a brief description of DNSSEC and E-DNSSEC protocols. After that, we present the resolution process of both DNSSEC and E-DNSSEC protocols. Then, we give a formal specification of these protocols in the applied 'pi-calculus'. Relying on this modeling, the confidentiality property of E-DNSSEC is verified by ProVerif. [ABSTRACT FROM AUTHOR]

The paper describes a concept of software tools for data stream processing. The tools can be used to implement parallel processing systems. Description of the task is presented in the first part of paper. The system is based on pipeline parallelism and was distributed for using on a cluster computer. The paper describes a base scheme and a main work algorithm of the system. Tasks are presented in π-calculus terms. The system process tasks as π-calculus automata. An actual application example is presented.

Observational equivalence allows us to study important security properties such as anonymity. Unfortunately, the difficulty of proving observational equivalence hinders analysis. Blanchet, Abadi & Fournet simplify its proof by introducing a sufficient condition for observational equivalence, called diff-equivalence, which is a reachability condition that can be proved automatically by ProVerif. However, diff-equivalence is a very strong condition, which often does not hold even if observational equivalence does. In particular, when proving equivalence between processes that contain several parallel components, e.g., P ∣ Q and P ′ ∣ Q ′ , diff-equivalence requires that P is equivalent to P ′ and Q is equivalent to Q ′ . To relax this constraint, Delaune, Ryan & Smyth introduced the idea of swapping data between parallel processes P ′ and Q ′ at synchronisation points, without proving its soundness. We extend their work by formalising the semantics of synchronisation, formalising the definition of swapping, and proving its soundness. We also relax some restrictions they had on the processes to which swapping can be applied. Moreover, we have implemented our results in ProVerif. Hence, we extend the class of equivalences that can be proved automatically. We showcase our results by analysing privacy in election schemes by Fujioka, Okamoto & Ohta, Lee et al., and Juels, Catalano & Jakobsson, and in the vehicular ad-hoc network by Freudiger et al. [ABSTRACT FROM AUTHOR]

There are numerous research articles on web service, composition, modeling, verification, and other problems. These research works are performed on the basis of formal methods, such as petri-net, pi-calculus, automata theory, and so on. Pi-calculus is a natural vehicle to model the mobility aspect in dynamic web services composition (DWSC). However, it has recently been shown that pi-calculus needs to be extended suitably to specify and verify DWSC. In this article, we consider the authority model for DWSC, extend pi-calculus in order to model dynamic attributes of system, and propose a automatic method for modeling DWSC based on extended pi-calculus. [ABSTRACT FROM PUBLISHER]

Session types are a formalism used to model structured communication-based programming. A binary session type describes communication by specifying the type and direction of data exchanged between two parties. When session types and session processes are added to the syntax of standard π -calculus they give rise to additional separate syntactic categories. As a consequence, when new type features are added, there is duplication of effort in the theory: the proofs of properties must be checked both on standard types and on session types. We show that session types are encodable into standard π -types, relying on linear and variant types. Besides being an expressivity result, the encoding (i) removes the above redundancies in the syntax, and (ii) the properties of session types are derived as straightforward corollaries, exploiting the corresponding properties of standard π -types. The robustness of the encoding is tested on a few extensions of session types, including subtyping, polymorphism and higher-order communications. [ABSTRACT FROM AUTHOR]

In order to solve the problem of not interworking the increment service provided by difference services providers in current mobile communication service,mobile communication process were defined as multiple independent Web services.The connection initialization,base station switching and mobile communication process were modeled by using PI-calculus.The PI-calculus expressions were encapsulated and combined.Modeling for PI-calculus can optimize the mobile communication service,and discover problems as soon as possible in the design stage to eliminate repeating business between difference service providers and to ensure their reusability and interoperability.

Applied process calculi include advanced programming constructs such as type systems, communication with pattern matching, encryption primitives, concurrent constraints, nondeterminism, process creation, and dynamic connection topologies. Several such formalisms, e.g. the applied pi calculus, are extensions of the the pi-calculus; a growing number is geared towards particular applications or computational paradigms. Our goal is a unified framework to represent different process calculi and notions of computation. To this end, we extend our previous work on psi-calculi with novel abstract patterns and pattern matching, and add sorts to the data term language, giving sufficient criteria for subject reduction to hold. Our framework can directly represent several existing process calculi; the resulting transition systems are isomorphic to the originals up to strong bisimulation. We also demonstrate different notions of computation on data terms, including cryptographic primitives and a lambda-calculus with erratic choice. Finally, we prove standard congruence and structural properties of bisimulation; the proof has been machine-checked using Nominal Isabelle in the case of a single name sort. [ABSTRACT FROM AUTHOR]

We present a type system based on session types that works on a conventional pi calculus. Types are equipped with a constructor that describes the two ends of a single communication channel, this being the only type available for describing the behaviour of channels. Session types, in turn, describe the behaviour of each individual channel end, as usual. A novel notion of typing context split allows for typing processes not typable with extant type systems. We show that our system guarantees that typed processes do not engage in races for linear resources. We assess the expressiveness of the type system by providing three distinct encodings – from the pi calculus with polarized variables, from the pi calculus with accept and request primitives, and from the linear pi calculus – into our system. For each language we present operational and typing correspondences, showing that our system effectively subsumes foregoing works on linear and session types. In the case of the linear pi calculus we also provide a completeness result. [ABSTRACT FROM PUBLISHER]

This paper presents a mechanisation of psi-calculi, a parametric framework for modelling various dialects of process calculi including (but not limited to) the pi-calculus, the applied pi-calculus, and the spi calculus. psi-calculi are significantly more expressive, yet their semantics is as simple in structure as the semantics of the original pi-calculus. Proofs of meta-theoretic properties for psi-calculi are more involved, however, not least because psi-calculi (unlike simpler calculi) utilise binders that bind multiple names at once. The mechanisation is carried out in the Nominal Isabelle framework, an interactive proof assistant designed to facilitate formal reasoning about calculi with binders. Our main contributions are twofold. First, we have developed techniques that allow efficient reasoning about calculi that bind multiple names in Nominal Isabelle. Second, we have adopted these techniques to mechanise substantial results from the meta-theory of psi-calculi, including congruence properties of bisimilarity and the laws of structural congruence. To our knowledge, this is the most extensive formalisation of process calculi mechanised in a proof assistant to date. [ABSTRACT FROM AUTHOR]