Scalable Techniques for Anomaly Detection

Computer networks are constantly being attacked by malicious entities for various reasons. Network based attacks include but are not limited to, Distributed Denial of Service (DDoS), DNS based attacks, Cross-site Scripting (XSS) etc. Such attacks have exploited either the network protocol or the end-host software vulnerabilities for perpetration. Current network traffic analysis techniques employed for detection and/or prevention of these anomalies suffer from significant delay or have only limited scalability because of their huge resource requirements. This dissertation proposes more scalable techniques for network anomaly detection. We propose using DNS analysis for detecting a wide variety of network anomalies. The use of DNS is motivated by the fact that DNS traffic comprises only 2-3% of total network traffic reducing the burden on anomaly detection resources. Our motivation additionally follows from the observation that almost any Internet activity (legitimate or otherwise) is marked by the use of DNS. We propose several techniques for DNS traffic analysis to distinguish anomalous DNS traffic patterns which in turn identify different categories of network attacks. First, we present MiND, a system to detect misdirected DNS packets arising due to poisoned name server records or due to local infections such as caused by worms like DNSChanger. MiND validates misdirected DNS packets using an externally collected database of authoritative name servers for second or third-level domains. We deploy this tool at the edge of a university campus network for evaluation. Secondly, we focus on domain-fluxing botnet detection by exploiting the high entropy inherent in the set of domains used for locating the Command and Control (C&C) server. We apply three metrics namely the Kullback-Leibler divergence, the Jaccard Index, and the Edit distance, to different groups of domain names present in Tier-1 ISP DNS traces obtained from South Asia and South America. Our evaluation successfully detects existing domain-fluxing botnets such as Conficker and also recognizes new botnets. We extend this approach by utilizing DNS failures to improve the latency of detection. Alternatively, we propose a system which uses temporal and entropy-based correlation between successful and failed DNS queries, for fluxing botnet detection. We also present an approach which computes the reputation of domains in a bipartite graph of hosts within a network, and the domains accessed by them. The inference technique utilizes belief propagation, an approximation algorithm for marginal probability estimation. The computation of reputation scores is seeded through a small fraction of domains found in black and white lists. An application of this technique, on an HTTP-proxy dataset from a large enterprise, shows a high detection rate with low false positive rates

MOLECULAR ASSESSMENT OF GENETIC DIVERSITY IN INDIAN ACCESSIONS OF ALOE VERA USING SSR MARKER

Objective: In this study Aloe vera (L.) Burm. f. collected from 12 states covering all the different agro-climatic zones of India were investigated for its genetic diversity analysis by using SSR marker assay.Methods: Total genomic DNA was isolated from young leaf samples using CTAB method. Twenty primers were selected which were used for Asparagus officinalis L a related species of A. vera and others were developed from available Aloe vera plant sequences with the help of primer 3 software. Similarity matrices and dendrogram were constructed by using NTSys software to show a phenetic representation of the genetic relationship. Polymorphic Information Content (PIC), the effective multiplex ratio (EMR) and Marker Index (MI) were calculated for the assessment of genetic diversity.Results: The neighbor-joining tree based on all SSR fragments of twelve Aloe vera germplasm accessions grouped into three major clusters. The similarity value ranged from 46 % to 100 %. The highest 100 % similarity was noted between Haryana and Uttar Pradesh accessions followed by 93% similarity between Haryana and Punjab accessions with Rajasthan. Minimum similarity was noted between Gujarat and Kerala accessions.Conclusion: This study revealed the rich genetic diversity among Aloe vera accessions from different agro-climatic zones of India. It is also concluded that SSR marker analysis can be a useful tool for the assessment of genetic diversity of the medicinal plants.Â

Day Time Sleepiness and Quality of Life Predicts Perceived Stress among Youth

The study examined the predictor of perceived stress among youth. The variables used in the current study were day time sleepiness, quality of life and perceived stress. The sample consists of 150 youth (81Male & 69 Female) with in the age range of 18-24 years. The Epworth Sleepiness Scale (ESS), World Health Organization Quality of Life (WHO-BRIEF), and Perceived Stress Scale (PSS) were used. The data were interpreted after obtaining the descriptive statistics i.e. Mean and SD, Pearson’s Product Moment correlation and step wise multiple regression analysis. The findings indicated that day time sleepiness and quality of life have a significant positive relation with perceived stress among youth. The step wise regression analysis found day time sleepiness and psychological health related quality of life are the predictors of perceived stress. Both the variable accounts for 39% of total variance in perceived stress among youth

Chaser Priori Wolf (CPW) Optimization an Improved Optimization Technique Video Content Classification and Detection

Optimizers play a crucial role in video object detection by promoting the training and improving the performance of the model. Optimizers are responsible for minimizing the loss function during training. The parameters of models are updated iteratively based on the gradients of the loss parameters. By continuously adjusting the parameters in the direction of the steepest descent, optimizers guide the model towards convergence, reducing the loss and improving the object detection performance. In the proposed paper hybrid optimizer named chaser priori wolf optimizer is proposed. The chaser priori wolf optimization is based on the hybridization of cat swarm optimization and coyote optimization. Well-known optimizers like SGD, ADAM, adagrad, adadelta and RMSprop are used as default optimizers by researchers. The proposed work introduced CPW optimizer which works for classification to improve the convergence and feature selection. The comparative result showed an increase in the performance of CNN based YOLO model. The results are compared concerning sensitivity, specificity and accuracy. Results clearly showed improvement in all performance metrics and the average improvement in comparison with state of art architecture is 10.3%

A review on regulatory control of chromium stress in plants

Chromium (Cr) is a non-biodegradable heavy metal that persists long in aquatic and terrestrial ecosystems and enters the food chain. It is cytotoxic even at low concentrations and reduces the yield of plants. Plants also have cellular mechanisms to manage the accumulation of metal ions inside the cell to diminish the possible injury from non-essential metal ions. This paper reviews current information on plant response to Cr, a key environmental pollutant. The harmful effects together with absorption, transfer, and aggregation of Cr are discussed. The roles of the cell wall, plasma membrane, and plant microbes as the primary hindrances for Cr ingression into the cell, along with sequestration and compartmentalization process, have also been discussed. Cr-generated oxidative injury is also regarded as the main deliberated effect of Cr toxicity.  It interferes with NADPH oxidases (plasma membrane) and the electron transport chains, which develop electron leakage. Some genes related to Cr stress in plants get expressed, and suppression produces protective effects by activating the signal transduction pathways. The expression of genes like BnaCnng69940D and BnaC08g49360D is increased, which is involved in protein kinase activity, signal transduction, and oxidoreductase activity. The increased mRNA levels of Cr stress response proteins, including HSP90-1 and MT-1, have been reported in the Brassica napus plant. The stressed environment around the plants may stimulate the biosynthesis of phytochelatins and metal-binding proteins, which have a protective role in plant’s growth and development.

Partial Loopholes Free Device Independent Quantum Random Number Generator Using IBM's Quantum Computers

Random numbers form an intrinsic part of modern day computing with applications in a wide variety of fields. But due to their limitations, the use of pseudo random number generators (PRNGs) is certainly not desirable for sensitive applications. Quantum systems due to their intrinsic randomness form a suitable candidate for generation of true random numbers that can also be certified. In this work, the violation of CHSH inequality has been used to propose a scheme by which one can generate device independent quantum random numbers by use of IBM quantum computers that are available on the cloud. The generated random numbers have been tested for their source of origin through experiments based on the testing of CHSH inequality through available IBM quantum computers. The performance of each quantum computer against the CHSH test has been plotted and characterized. Further, efforts have been made to close as many loopholes as possible to produce device independent quantum random number generators. This study will provide new directions for the development of self-testing and semi-self-testing random number generators using quantum computers.Comment: We present a scheme by which one can generate device independent quantum random numbers by use of IBM quantum computers that are available on the clou

Group 14 and 15 elements as building blocks for low dimensional functional nanostructures

Carbon nanotubes (CNTs) are an interesting allotrope of carbon which can have a wide range of applications as they have extraordinary mechanical, electrical and thermal properties. All this makes CNTs an interesting nanomaterial for different applications ranging from mechanical sensors to electrical microelectrodes and even biological applications due to their biological compatibility. Beside the excellent material properties, the use of special structuring of these materials is of great importance. The random orientation of CNTs cannot be controlled which usually leads to irreproducible material which is not suitable for real world applications. Therefore, the controlled growth of vertically aligned carbon nanotubes (VACNTs) is considered in this work. VACNTs have been grown on Si/SiO2 substrates using a water-assisted chemical vapor deposition technique. By this technique highly crystalline, pure, low-layer multiwalled CNTs with a vertical orientation to the substrate are obtained. The parameters for the growth are optimized and even structuring of the VACNTs is possible obtaining VACNTs with different heights in one synthesis step. This structuring is the used to construct a nano-microstructured artificial-hair-cell-type sensor as an example for a mechanical sensor which can measure three-dimensional forces by the changing contact resistance between neighboring CNT bundles of different heights. Because to the excellent electrical properties together with the highly-increased surface area due to the vertical alignment of VACNTs, they are compared to randomly oriented CNTs for microelectrode applications. In this, the advantage of vertical alignment becomes clear in the dramatic decrease in impedance and enormous increase in capacity. These microelectrodes are then tested for biological applications for which the compatibility and growth pattern of cortical neurons on VACNTs is studied. While CNTs represent one-dimensional systems, also two-dimensional materials related to carbon such as graphene oxide and reduced graphene oxide are studied and used for gas-adsorption as well as liquids absorbents in combination with bacterial cellulose in the form of aerogels. Finally, phosphorene as an example of a two-dimensional material closely related to graphene is synthesized. Phosphorene, although structurally similar to graphene, it has a band gap in contrast to graphene which makes it an interesting material field-effect transistor devices as shown in this work

Agency Theory and Internationalization: A Critical Assessment of Literature

This study consolidates the state of academic research using agency theory to explain the various phenomena’s in the multinational firm’s (MNCs) context. Based on the systematic review of the literature, the author finds that agency theory is used to examine the degree of internationalization, international diversification, born global internationalization, and governance issues in various modes of foreign entries. The author classifies the literature in three broad themes: corporate governance, firm ownership, and born global firms. Agency theory is also used to examine the impact of top management characteristics, board structure, ownership by domestic investors, foreign investors, business group firms, family ownership, and state ownership on the firm internationalization decisions. The study concludes with the research gaps and future research directions