Shriram K. Vasudevan

Sybil Guard: Defending Against Sybil Attacks via Social Networks

Peer-to-peer and other decentralized, distributed systems are known to be particularly vulnerable to Sybil attacks. In a Sybil attack, a malicious user obtains multiple fake identities and pretends to be multiple, distinct nodes in the system. By controlling a large fraction of the nodes in the system, the malicious user is able to ―out vote‖ the honest users in collaborative tasks such as Byzantine failure defenses. This paper presents Sybil Guard, a novel protocol for limiting the corruptive influences of Sybil attacks. Our protocol is based on the ―social network‖ among user identities, where an edge between two identities indicates a human-established trust relationship. Malicious users can create many identities but few trust relationships. Thus, there is a disproportionately-small ―cut‖ in the graph between the Sybil nodes and the honest nodes. Sybil Guard exploits this property to bound the number of identities a malicious user can create. We show the effectiveness of Sybil Guard both analytically and experimentally.

Hybrid Steganography using Visual Cryptography and LSB Encryption Method

The biggest threat in the data transfer is through any medium is, the chance for it being hacked. Any information, these days are hackable. So utmost care has to be taken for any communication to be done, in particular, if confidential. The so claimed most sheltered data have also been hacked nowadays. The digital watermarking is a widely used method for information hiding to authenticate as well as secure the content in an image. This paper describes a hybrid watermarking technique to embed a secret message into an image using visual cryptography and SLSB(Selected Least Significant Bit) encryption techniques. This paper becomes very special in few aspects, all of them are explained in a detailed way in the chapters.

DISTRIBUTIVE POWER MIGRATION AND MANAGEMENT ALGORITHM FOR CLOUD ENVIRONMENT

In cloud computing, the resources are provided as service over the internet on demand basis. The resources such as servers, networks, storage, applications are dynamically scaled and virtualized. The demand grows gradually for each virtual machine in a cloud computing environment over time. So, it is necessary to manage the resources under each cluster to match the demand in order to maximize total returns by minimizing the power consumption cost. It can be minimized by applying minimal virtual design, live migration and variable resource management. But, the traditional way of scheduling doesn’t meet our expected requirements. So we introduce the distributive power migration and management algorithm for cloud environment that uses the resources in an effective and efficient manner ensuring minimal use of power. The proposed algorithm performs computation more efficiently in a scalable cloud computing environment. The results indicate that the algorithm reduces up to 30% of the power consumption to execute services.

Heuristic Approaches with Energy Management for Node Placement in Wireless Sensor Networks

ABSTRACT In Wireless Sensor Network, Device placement is a key factor for determining the coverage, connectivity, and cost along with lifetime. Managing the sensor nodes is not much easier while comparing mobile Ad ¬ Hoc Networks. But the same approach can be implemented to manage the WSN. Addressing the management of the whole network is omitted and a probabilistic scheme where only a subset of nodes is managed is provided for light ¬ weight and efficient management. Relay node placement in heterogeneous WSN are formulated using a generalized node placement optimization problem to minimize the network cost with lifetime constraint, and connectivity. Based on the constraints two scenarios are used. In the first scenario relay nodes are not energy constrained, and in the second scenario all nodes are energy limited. As an optimal solution a two-phase approach is proposed. The placement of the first phase relay nodes (FPRN), which are directly connected to Sensor Nodes (SN), is modeled as a minimum set covering problem. To ensure the relaying of the traffic from the FPRN to the base station, three heuristic schemes are proposed to place the second phase relay nodes (SPRN). Some of the heuristic approaches available are Nearest¬ to ¬ BS¬ First algorithm (NTBF), Max¬ Residual¬ Capacity¬ First algorithm (MRCF) and Best¬ Effort¬ Relaying algorithm (BER). Our contribution is centered on a distributed self organizing management algorithm at the application layer by organizing the management plane by extracting spatiotemporal components and by selecting manager nodes with several election mechanisms applied to wireless sensor nodes. Furthermore, a lower bound on the minimum number of SPRN required for connectivity is provided.

Trends In Task Allocation For Multicore System

As the functionality in real-time embedded systems becoming complex, there has been a demand for higher computation capability, exploitation of parallelism and effective usage of the resources. Further, technological limitations in uniprocessor in terms of power consumption, instruction level parallelism reaching saturation, delay in access of memory blocks; directed towards emergence of multicore. Multicore design has its challenges as well. Increase in number cores has raised the demand for proper load distribution, parallelizing existing sequential codes, enabling effective communication and synchronization between cores, memory and I/O devices. This paper brings out the demand for effective load distribution with analyzes and discussion about the various task allocation techniques and algorithms associated with decentralized task scheduling technique for multicore systems. This paper also addresses on the multithreaded architecture, where parallel tasks are formulated from sequential code blocks and finally on the techniques to parallelize the sequential code block. Full Text: PDF DOI: http://dx.doi.org/10.11591/ijece.v6i6.10140

ADAPTING LINUX AS MOBILE OPERATING SYSTEM

In this fast growing world, people are increasingly mobile; everything is fast, connected and highly s ecured. All these have put up the requirements on mobile de vices and leads to several features being added in the mobile operating systems and its architecture. The development of the next generation software platfor m based on Linux for mobile phones provides enhanced user experience, power management, cloud support and openness in the design. In spite of many studie s on Linux, the investigations on the challenges an d benefits of reusing and adapting the Linux kernel t o mobile platforms is very less. In this study, a s tudy on architecture of the Linux, its adaptations for a mo bile operating system, requirements and analysis fo r Linux mobile phones, comparison with android and solution technologies to satisfy the requirements for a Lin ux mobile operating system are analysed and discussed.

Enhanced Link Redirection Interface for Secured Browsing using Web Browser Extensions

In the present world scenario where data is meant to be protected from intruders and crackers, everyone has the fear to keep their private data safe. As the data is stored on servers accessed through websites by browsers, it’s the browsers, which act as a medium between a user and the server to send or receive data. As browsers send data in plain text, any data which is sent could easily be intercepted and used against someone. Hence this led to the use of Transport Layer Security (TLS) and Secure Socket Layer (SSL), which are cryptographic protocols designed to provide communication security over the Internet. A layer on top of SSL/TLS, support an encrypted mode, also known as HTTPS (HTTP Secure). Therefore, one of the main aspect of security lies in the website supporting HTTPS. Most websites have support for this encrypted mode and still we use an unencrypted mode of websites because a common user is unaware of the advancements in the field of technology. So to help us, in browsers, we have extensions or plug-ins to ease our life. This paper proposes the idea to implement the security measures in the web browsers.

Cane Free Obstacle Detection Using Sensors and Navigational Guidance Using Augmented Reality for Visually Challenged People

The project concentrates on obstacle detection for visually impaired people using IR, Ultrasonic sensors and TSOP receiver which is of less cost, fast and efficient. Shortest distance algorithm is the method used to find the obstacles at each region sent from the TSOP receiver mounted on each angles. This works in environments such as indoor and outdoor. Experience comes from learning and the important requirements for learning will be the sense of vision of what normal human being sees and observes in the real world. But in the case of VI people, sense of vision will not help them in learning where other senses like ears, touch, smell helps them in various situations. The whole setup is wearable and lightweight mounted on a belt to make the VI people to walk into any situation like pits, steps by providing haptic feedback as the output. The project uses Arduino mega which helps us to program ease and also helps in testing various parameters with the available open source library routines. Since the targeted user is VI people, navigational guidance can be done through Augmented Reality domain as the technology is growing wide and can give more reliable to the user.

A novel algorithm for triangulating 2d point clouds using multi-dimensional data structures and nearest neighbour approach

Generating a mesh from a point cloud has always been a complex and tedious task. It requires many guidelines to be followed and geometry specific boundary condition to be taken care of. Mostly we end up writing a new algorithm for each scenario. The existing algorithms like Delaunay triangulation end up taking a lot of time without taking care of the internal holes properly. Also the convergence is not guaranteed. In this paper, we present a recursion free algorithm for triangulating a structured surface with n-vertices with or without holes using Ball trees. The algorithm takes the input in the form of an image, creates a mask for the object to be triangulated and then creates a mesh for it with respect to computed vertices.

An Interactive and Intelligent Tool for Circuit Component Recognition Through Virtual Reality

The electronic products that support the needs in our daily life require a long drawn out process for its development and building. Every step from scratch i.e. requirement collection to integration and testing, involves a lot of time consuming tasks. Generally, a technically sound person with good knowledge in simulation is assigned to carry out these tasks, yet it fritters away time. The idea proposed here is an application for generating NetList for the circuit drawn through hand gesture, powered by virtual reality. The application gets input from the user’s hand gesture using an additional hardware called leap motion sensor. This enables the users to draw any kind of circuit, of any size with any number of components. The completed circuit is captured and further processing is carried out. The circuit is isolated, recognized and segregation of the wires and components takes place in the consecutive phases. The next step involves identification of individual components and the aggregated NetList will be generated in the final step. And also, complex circuit which cannot fit into a limited space can be visualized in the virtual environment.