Prem Chandra Saxena

A load balancing strategy for Cloud Computing environment

Information and communication technology has been growing rapidly for the last few decades. In todays age of information and globalization massive computing power is desired to generate business insights and competitive advantage [1]. Cloud Computing is an emerging technology and has attracted a lot of attention in both commercial and academic spheres. It is growing very fast and provides an alternative to conventional computing. There are cloud service providers who provide services in a flexible manner. The main goal of cloud service provider is to establish an efficient load balancing algorithm which ensures a fair distribution of loads among virtual machines and better resource utilization. In this paper we present a heuristic based load balanced scheduling model for efficient execution of tasks. The proposed model balances the loads coming from several users among datacenters and hence it offers better resource utilization and high availability in the form of improved response time and turnaround time. The proposed algorithm is implemented using CloudSim simulator and the result shows that the proposed algorithm outperforms to existing algorithms on similar objectives.

Fifty years of automata simulation: a review

Automata theory is an important subject in computer science and quite consequently, simulation of automata for pedagogical purposes is an important topic in computer science education research. This article reviews the major initiatives in the field of simulation of automata in the last five decades with emphasis on those automata simulators actually used at universities for teaching. A classification of the automata simulators on the basis of their design paradigms has been developed where they have been classified broadly into language based automata simulators and visualization centric automata simulators. Some salient trends in the research on simulation of automata are also identified. The article concludes with an advocacy for continuing research on simulation of automata and integration of automata simulators in teaching.

A compiler‐based toolkit to teach and learn finite automata

This paper introduces a compiler technology based approach to model and simulate finite automata for pedagogical purposes. The compiler technology helps to define a language to formally model finite automata and to develop a toolkit to simulate them efficiently. The language is called Finite Automaton Description Language (FADL) and the toolkit is based on it. A fast single‐pass compiler is used to compile a finite automaton defined in FADL. Then an interpreter is used to simulate the working of the compiled finite automaton for any input string. The nondeterminism of a Nondeterministic Finite Automaton (NFA) is simulated using backtracking. A tool to view the transition diagram of the finite automaton is provided. A Deterministic Finite Automaton (DFA) can be additionally compiled using an optimizing compiler that also minimizes the number of states. Tools for converting an NFA to a DFA and for converting a DFA to a Turing machine are also provided. A preliminary testing of the toolkit has been performed in which the participating students observed that the toolkit is an interesting teaching tool and it helped them to acquire a better perception about finite automata.

A new practicum in compiler construction

This article introduces a compiler construction practicum based on the implementation of a compiler for a small C‐like language. The compiler has three phases, viz., lexical analysis, syntax analysis, and intermediate code generation. It uses some venerable principles of compiler construction like recursive descent parsing, syntax directed translation, and backpatching. The practicum is appropriate for pedagogical purposes because of its balanced design and the availability of an open source reference implementation of the compiler with a source code size of 2.2 KLOC only.

Teaching purpose compilers: an exercise and its feedback

This paper presents an exercise to teach fundamental compiler construction issues. Four simple compilers, in both source and executable forms, were distributed among the students. The students studied the source codes and the accompanying documents. They performed various experiments with the compilers that included modifying the source codes, reengineering phases and implementing new phases and utilities. The students were enthusiastic about the practical knowledge they gained from the exercise. More than fifty students undertook the exercise and the overall response was quite satisfactory.

A Secure Anonymous E-Voting System Using Identity-Based Blind Signature Scheme

Electronic voting is an alternative mechanism of ballot based voting which empowers voters to cast their secret and secure vote electronically over a public channel. Many onward-thinking countries are adopting the electronic voting system to upgrade their election process. E-voting system is more complicated to construct. Thus it expects more security as compared to the postal voting system. The objective of the paper is twofold. Firstly, we proposed an efficient blind signature scheme using the identity-based cryptosystem in the random oracle model. The proposed scheme uses the combination of Boldyreva’s blind signature scheme and Choon-Cheon’s Identity-based signature. Additionally, we reduce its security to the Gap Diffie-Hellman Complexity (GDH). Under the adaptive chosen message and ID attacks it is secure against existential forgery attack. We show our proposed system performed better as compared to existing systems. Secondly, we construct an E-voting system based on our ID-based blind signature and Boneh’s short signature scheme (EVS-ID-BS) that fulfills the E-voting security requirements. To the best of our knowledge, EVS-ID-BS is the first practical implementation of E-voting system based on ID-BS Scheme which is constructed in the random oracle model. Proposed EVS-ID-BS scheme provides batch verifiability for a significantly large number of voters, needs less bandwidth cost and require less interaction with election authority.

An Untraceable Identity-Based Blind Signature Scheme without Pairing for E-Cash Payment System

Blind signature is an interesting cryptographic primitive which allows user to get signature on his document from signatory authority, without leaking any information. Blind signature is useful in many e-commerce applications where user’s anonymity is the main concern. Since the Zhang et al., was the first to propose the identity based blind signature, many schemes based on bilinear pairing have been proposed. But the computational cost of pairing operation on elliptic curve is around 20 times the point multiplication on an elliptic curve. In order to save the running time, we present a new Identity-Based Blind Signature (ID-BS) scheme whose security is based on elliptic curve discrete logarithm problem (ECDLP). Performance comparison shows that proposed scheme reduces the cost of computation. Security analysis shows that proposed scheme is secure against the adversary and achieves the property of blindness and Non-forgeabillity. At the end; we propose an e-cash payment system based on our ID-based blind signature scheme.

Fuzzy statistical dependency and normalisation in fuzzy statistical database

Most of the statistical databases developed so far use precise data. But in the real world, most of the data is imprecise in nature. Fuzzy set theory has proven to be a good choice for accomplishing the task of imperfect data particularly in statistical database and fuzzy statistical database has arisen as a result. In this paper, we introduce the concept of fuzzy statistical dependency, a dependency between the attributes of fuzzy statistical database which allows the database developer to develop a consistent logical modelling tool for fuzzy statistical database. We also discuss the fuzzy statistical equality for comparison of attributes in fuzzy statistical database. To eliminate the redundancy in fuzzy statistical database, fuzzy statistical normal forms are defined which present a framework for the database developer to maintain consistency in the fuzzy statistical database. Algorithms for implementation of fuzzy statistical normal forms are also discussed.