Computer Science and Engineering

The task of automatically analyzing sentiments from a tweet has more use now than ever due to the spectrum of emotions expressed from national leaders to the average man. Analyzing this data can be critical for any organization. Sentiments are often expressed with different intensity and topics which can provide great insight into how something affects society. Sentiment analysis in Twitter mitigates the various issues of analyzing the tweets in terms of views expressed and several approaches have already been proposed for sentiment analysis in twitter. Resources used for analyzing tweet emotions are also briefly presented in literature survey section. In this paper, hybrid combination of different model's LSTM-CNN have been proposed where LSTM is Long Short Term Memory and CNN represents Convolutional Neural Network. Furthermore, the main contribution of our work is to compare various deep learning and machine learning models and categorization based on the techniques used. The main drawback of LSTM is that it's a timeconsuming process whereas CNN do not express content information in an accurate way, thus our proposed hybrid technique improves the precision rate and helps in achieving better results. Initial step of our mentioned technique is to preprocess the data in order to remove stop words and unnecessary data to improve the efficiency in terms of time and accuracy also it shows optimal results when it is compared with predefined approaches.

Due to technological advancement, clouds are becoming an important platform for processing different multimedia applications. These high performance environments emphasize the role of Information and Communication Technology (ICT) which is essential for the survival of global business to achieve better system design and operational objectives. The development of cloud computing represents a fundamental change in cloud and ICT services for multimedia applications with more functionality and increasing number of users. As multimedia data comprises of images, video, audio, text and these applications requires fast speed and large storage for transferring data, thus it is a crucial issue to choose best cloud services which meets all the requirements of the users for storing and managing multimedia data in heterogeneous mobile environment. The aim of this paper is to propose computational intelligence decision making model that can enable users to use cloud services during mobility accur...

Distributed Environments are touching new heights, becoming more useful, popular and more complex with the emergence of service oriented architecture and computing technologies like peer-to-peer, autonomic, pervasive and grid etc. These technologies aim to enable large scale resource sharing. Security is a big and challenging issue in these environments as it involves the federation of multiple heterogeneous, geographically distributed autonomous administrative domains. The dynamic and multi-institutional nature of service oriented environments like grid and web introduces several challenging security issues that require new technical approaches. This paper proposes a privacy, trust and policy based authorization framework for grid and web services, but, in fact can be amended for any distributed, service oriented computing environment as most of the elements defined in the framework are general and adaptable in other computing environments. The framework is intended to provide a simple, powerful, flexible and scalable authorization infrastructure for services exposed in a large scale distributed environment. The paper also discusses a prototype implementation of the proposed framework. For implementation, we are making use of web services security specifications supported by WSE 3.0. Sample implementation has shown that the architecture is capable of meeting the identified security requirements and the approach is workable.

The evolution of distributed computing technologies like grid computing, peer-to-peer computing, pervasive computing, ubiquitous computing, autonomic computing, cloud computing etc. has led to the development of complex virtual systems. These systems enable sharing of resources and services distributed over geographically dispersed, heterogeneous, autonomous administrative domains and allow one to efficiently perform a compute or storage intensive task by harnessing the features available over other domains. The resources and services provided by service providers are generally protected by complex access control policies. These access control policies are expressed using policy specification languages. One of the popular, exhaustive and feature rich access control policy specification language is XACML, which is an OASIS standard also. The XACML policies are specified either manually or using automated XACML policy specification tools. Among major problems that policy administrators face is the problem of conflict policies. Conflict policies can have serious consequences and may lead to unauthorized access. This paper presents the design, implementation and evaluation of a conflict policy detection mechanism that can be used by policy administrators to proactively detect conflict XACML policies present in a policy database. This saves administrators and initiators of job from unnecessary problems arising due to presence of conflicts. The mechanism presented is simple, scalable, efficient and can be used to detect policies conflicting with respect to subject, resource, and action attributes. The mechanism has been evaluated by simulating a distributed policy based authorization and XACML access control system. A number of conflict policies of different nature have been injected in the policy database and conflicts have been identified through proposed XACML conflict policy detection algorithm. The implementation results show that the mechanism efficiently detects conflict policies having conflicts with respect to subject, resource and action attributes. This demonstrates that the approach is workable and can be used to detect conflict policies among a set of XACML policies.

Large scale distributed systems enable sharing of resources and services scattered over geographically dispersed, heterogeneous, autonomous administrative domains. Two main entities interacting with each other over a distributed system are service requesters and service providers. The service requesters belonging to a particular administrative domain may request access to resources/services available over same or other administrative domains. Similarly a service provider belonging to a particular administrative domain may expose its resources/services over same or other administrative domains. The service requesters belonging to one administrative domain generally have different access rights in different administrative domains. Determining what a service requester is authorized to do in the same or other administrative domains is a difficult task. The overall authorization and access control becomes more complex when service providers attach authorization and access control related policies with their resources/services and provide access to those resources/services based on conformance to established policies. These policies may include authentication, privacy, trust, network workload, business and management etc. related aspects of authorization and access control. Designing an authorization and access control system for such an environment is a complex task and introduces many challenging technology and management related issues. In this paper we have made an attempt to define and implement a policy based authorization and access control framework that can be used to determine the access rights of a subject in different administrative domains and supports policy-based access to resources/services scattered over a distributed system. The framework proposed is scalable, flexible and has been implemented through web services. The paper also discusses prototype implementation of the proposed framework.

Grid computing allows sharing of services and resources distributed over geographically dispersed, heterogeneous, autonomous administrative domains. As a domain generally has no idea about the trustworthiness of other domains, it may hesitate in accessing shared services and resources provided by other domains. Accessing resources and services from untrusted domains may pose dangerous consequences to the source domain. Trust is an important parameter in achieving faithful domain to domain interaction. Domains must be able to determine the trustworthiness of each other for the access of a particular service. Domains must also provide trust based access to resources and services that they expose in the environment. This paper describes different facets associated with trust issues among different entities in a grid environment and proposes a trust model to establish and manage trust relationships. The trust model provides support to calculate direct as well as recommended trust. Based on this model, a trust based authorization framework is proposed that can be used to provide trust based access to grid services. The goal of the model is to encourage trust based domain to domain interaction and increase the confidence of domains in accessing shared resources provided by other domains. The framework has been implemented in .NET environment with the support of WSE 3.0 toolkit. The framework has been evaluated by implementing a scenario that involves enforcement of different trust policies. The time taken by the enforcement component to evaluate trust policies has been noted. The results obtained from the implementation imply that the approach is workable and can be used to provide trust based access to grid services.

The goal of Grid computing is to create illusion of a simple yet large and powerful self managing virtual computer out of a large collection of connected heterogeneous systems sharing various combinations of resources. Such an environment introduces challenging trust related issues as both service providers and users can come from mutually distrusted administrative domains and any of them can behave maliciously. The use of trust evaluation simplifies the security architecture and is evaluated on the basis of a number of parameters like trust decay, reputation, trust updation, transitivity etc. A number of models have been proposed by different researchers for the evaluation of trust but many of them have missed one or the another required parameters that are necessary for the evaluation of trust in a comprehensive way. In this paper a novel approach for evaluation of trust has been proposed that insists on the use of a number of imnportant parameters to calculate trust in a comprehensive way.

Grid computing is a form of distributed computing that provides a platform for executing large-scale resource intensive applications on a number of heterogeneous computing systems across multiple administrative domains. Therefore, Grid platforms enable sharing, exchange, discovery, selection, and aggregation of distributed heterogeneous resources such as computers, databases and visualization devices. Job and resource scheduling is one of the key research area in grid computing. In a grid computing environment, a scheduler is responsible for selecting the best suitable computing resources in the grid for processing jobs to achieve high system throughput. Further, grouping the fine grained jobs according to the processing capability of available resources results in better throughput, resource utilization and low communication time. Motivation of this study is to encourage and help the amateur researcher in the field of grid computing, so that they can understand easily the concept of scheduling, job grouping and can contribute in developing more efficient and practical scheduling algorithm. In this paper, we compared three job grouping based scheduling algorithms that will benefit interested researchers to carry out further work in this thrust area of research.

The purpose of this paper is to present the design of a secure and more advanced authentication scheme for executing secure financial transactions over Internet. There has been continuous change in technology day by day, so security mechanisms like authentication schemes are also required to be updated. The security measures have very crucial role in banking and financial sector. For any internet application which deals with personal and private information exchange, single tier authentication is inadequate. Authentication schemes that imply more than one tier for authentication are comparatively safer than single tier authentication scheme. Properly designed secure authentication mechanisms are more fraud deterrent. Various multi-tier authentication schemes have been proposed and implemented in various computing domains. The main drawback of these schemes is that most of them do not provide security against insider attacks. In case of Cloud Computing, another drawback is that the whole authentication control lies toward the server side. It is very hard to trust the third party server in Cloud Computing. This work proposes a scheme in which authentication process is carried out in two levels or two tiers. First tier uses simple username and password. Second tier is pre-determined series of steps. The advantage of this scheme is that it does not require any additional hardware and software. So this can be used and accessed from anywhere across the globe.

Cloud Computing moves computing and storage tasks from individual systems to the Cloud thereby reducing the burden at user's end. It enables the delivery of hardware and software resources over the Internet as a utility. Cloud Computing offers on-demand services with elasticity and scalability on pay per use basis. There are many problems that the organizations face when they migrate their data to the Cloud. Most of the legacy applications are not portable and must be rebuilt in order to fit the target cloud environment. The proposed migration scheme helps the user to migrate the database schema secured with RBAC to the Cloud with much ease. The XML file is generated which carries all the relevant information regarding the roles and database schema of the application. The application at Cloud service provider's end reads the XML file and allocates the space and creates the database schema along with RBAC on the Cloud without much user involvement. The proposed scheme is interoperable and has been demonstrated with a case study.

The purpose of this paper is to present a survey of XML-based security standards that can be used for handling security requirements of distributed computing systems like Grid and Cloud. Distributed systems are expanding and their growth is apparent from the advancements in the field of distributed computing technologies like Grid, Peer-to-peer, Cloud, Pervasive Systems etc. As a result of this expansion, security requirements are also increasing and becoming important. The expansion of Grid and Cloud demands new security standards for handling specialized security requirements and concerns of these systems. Different security standards are in use for handling security requirements of different systems. This paper presents a survey of important XML-based security standards, identifies general and specialized security requirements of Grid and Cloud like systems and then relates them to security standards. The paper also presents a general, security standards based view of distributed computing systems showing the applicability of XML-based security standards in handling security concerns of these systems.

Cloud Computing is the latest and emerging trend in information technology domain. It offers utility-based IT services to user over the Internet. Workflow scheduling is one of the major problems in cloud systems. A good scheduling algorithm must minimize the execution time and cost of workflow application along with QoS requirements of the user. In this paper we consider deadline as the major constraint and propose a score based deadline constrained workflow scheduling algorithm that executes workflow within manageable cost while meeting user defined deadline constraint. The algorithm uses the concept of score which represents the capabilities of hardware resources. This score value is used while allocating resources to various tasks of workflow application. The algorithm allocates those resources to workflow application which are reliable and reduce the execution cost and complete the workflow application within user specified deadline. The experimental results show that score based algorithm exhibits less execution time and also reduces the failure rate of workflow application within manageable cost. All the simulations have been done using CloudSim toolkit.

Cloud Computing refers to a paradigm whereby services are offered via internet using pay as you go model. Services are deployed in data centers and the pool of data centers is collectively referred to as "Cloud". Data centers make use of scheduling techniques to optimally allocate resources to various jobs. Different scenarios require different scheduling algorithms. The selection of a particular scheduling algorithm depends upon various factors like the parameter to be optimized (cost or time), quality of service to be provided and information available regarding various aspects of job. Workflow applications are the applications which require various sub-tasks to be executed in a particular fashion in order to complete the whole task. These tasks have parent child relationship. The parent task needs to be executed before its child task. Workflow scheduling algorithms are supposed to preserve dependency constraints implied by their nature and structure. Resources are allocated to various sub-tasks of the original task by keeping into account these constraints. In this paper, various workflow scheduling algorithms have been surveyed. Some algorithms have been found to optimize cost, some have been found to optimize time, some focuses on reliability, some focuses on availability, some focuses on energy efficiency, some focuses on load balancing or some focuses on a combination of these parameters. A lot of work has already been done in the area of workflow scheduling but still, we feel that there is a need and lot of scope in applying other optimization techniques, like intelligent water drops, to schedule workflow applications.

Grid infrastructures provide an environment for high performance computing by combining heterogeneous, widely distributed computational resources into a single cohesive computing infrastructure. One of the key goals of grid computing infrastructure is to provide an environment where users can share resources across heterogeneous domains. In such an infrastructure security is the major concern. Security itself is composed of various sub-issues like authentication, authorization, single sign-on, data integrity, confidentiality etc. Authorization deals with the issue like who is authorized to access which resource and under what condition i.e. controlling access to resources based on conditions. An authorization system must address different concerns like scalability, fine-grain access control, context based authorization, continuous decision enforcement. This paper proposes an authorization framework which addresses above issues in making access decision on the resource. This paper also discusses a prototype implementation of the framework and results show that framework is workable and addresses all issues related to authorization and access control.

Grid computing is a new paradigm for accessing resources distributed across organizational boundaries using computer networks. It allows for new ways of accessing & using remote resources. This new paradigm demands for several new concepts concerning security, especially authentication and authorization. The most commonly used security framework for grid system is Grid Security Infrastructure. It makes use of proxy certificates & private keys as credentials for allowing single sign on and delegation of rights. Single Sign-On (SSO) are the desired feature of computational grids. Although there are several ways to implement single sign-on and delegation but in this paper, these have been implemented on Alchemi.NET based grid computing framework through X.509 proxy certificates.

It is known facts that satellites are used to receive the signal at geostationary orbit by remaining stationary above a particular point on the Earth. The orbit that is chosen for a satellite depends upon its application. Those used for direct broadcast television use geostationary orbit. Many communication satellites similarly use geostationary orbit. Other satellite systems used for satellite phones use Low Earth orbiting systems. Similarly, satellite systems used for navigation like Nav-star or Global Positioning (GPS) system occupy a relatively Low Earth Orbit. There are also many other types of satellites : Weather satellites Research satellites and many others. Each will have its own type of orbit depending upon its application. The actual satellite orbit that is chosen will depend on factors including its function, and the area of serving. At some instances, the satellite orbit may be as low as 100 miles (160 km) for a Low Earth Orbit (LEO), whereas others may be over 22 000 ...

critical step. A single page has a data size of 40 This paper comlpares three different methods for controlling data flow over high speed wide area networks. It presents a novel mechanism that measures the exact receiver capabillities in order to improve the rate based flow control alg,orithm. Unlike standard protocols like TCP/IP with their credit based flow control, the new protocol DSTP uses this special rate based scheme. With additional optimizations, the protocol is able to reach both, high transmission speed and a nearly optimal usage of bandwidth.

A mobile ad-hoc network (MANETs) is an infrastructure less network in which the mobile nodes communicate with each other. Due to its various characteristics like highly dynamic topology and limited battery power of the nodes, routing is one of the key issue. Also, it is not possible to give a significant amount of power to the mobile nodes of ad-hoc networks. Because of all this the energy consumption is also an important issue. Due to limited battery power, some other issues like if some node gets fail, which results in loss of data packets and no reliable data transfer has been raised. In this paper, an algorithm is proposed for data transmission which detects the node failure (due to energy) before it actually happens. Because of this network lifetime gets improved. The proposed routing algorithm is energy efficient as compared to AODV routing algorithm. The performance is analyzed on the basis of various performance metrics like Energy Consumption, Packet Delivery Ratio, Network Life Time, Network Routing Overhead and number of Exhausted nodes in the network by using the NS2 Simulator.