Conference Papers
Permanent URI for this collectionhttps://idr.nitk.ac.in/handle/123456789/28506
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Item Towards evaluating resilience of SIP server under low rate DoS attack(2011) Kumar, A.; Santhi Thilagam, P.S.; Pais, A.R.; Sharma, V.; Sadalkar, K.Low rate Denial-of Service, DoS, attack recently emerged as the greatest threat to enterprise VoIP systems. Such attacks are difficult to detect and capable of discovering vulnerabilities in protocols with low rate traffic and it noticeably affects the performance of Session Initiation Protocol, SIP, communication. In this paper, we deeply analysis the resilience of SIP server against certain low rate DoS attacks. For this purpose we define performance metrics of SIP server under attack and non-attack scenarios. The performance degradation under attacks gives a measure of resilience of the SIP server. In order to generate normal SIP traffic and the attacks, we defined our own XML scenarios and implemented them using a popular open source tool known as SIPp. The system under evaluation was an open source SIP server. © 2011 Springer-Verlag.Item 3D Estimation and visualization of motion in a multicamera network for sports(2011) Kumar, A.; Chavan, P.S.; Sharatchandra, V.K.; Sumam David, S.S.; Kelly, P.; O’Connor, N.E.In this work, we develop image processing and computer vision techniques for visually tracking a tennis ball, in 3D, on a court instrumented with multiple low-cost IP cameras. The technique first obtains 2D ball tracking data from each camera view using 2D object tracking methods. Next, an automatic feature-based video synchronization method is applied. This technique uses the extracted 2D ball information from two or more camera views, plus camera calibration information. In order to find 3D trajectory, the temporal 3D locations of the ball is estimated using triangulation of correspondent 2D locations obtained from automatically synchronized videos. Furthermore, in order to improve the continuity of the tracked 3D ball during times when no two cameras have overlapping views of the ball location, we incorporate a physics-based trajectory model into the system. The resultant 3D ball tracks are then visualized in a virtual 3D graphical environment. Finally, we quantify the accuracy of our system in terms of reprojection error. © 2011 IEEE.Item Optimized low power low cost pulse oximeter for remote patient monitoring(IEEE Computer Society, 2013) Agrawal, N.; Agrawal, S.; Kumar, A.; Ramesh Kini, R.M.Pulsoximeter is a medical instrument for monitoring the blood oxygenation of a patient. This type of monitoring is especially useful for new born infants, during surgery and in determining Hypoxia. Blood oxygen content is an important indicator of human patient health and during anaesthesia. This aspect can be monitored by measuring the oxygen percentage in the blood timely and accurately with the help of our device. As our device is non invasive it proves out to be comfortable for the new born. Our slight modification to the standard approach that utilises pulse oximeter or Photoplethysmograph for this purpose, assures considerable decrease in current consumption thereby reducing overall power consumption which makes our device a low power device that can be used with much ease at places where power consumption is an issue. Patient's health parameters can be continuously monitored over a low power wireless network which aids in mobile monitoring. © 2013 IEEE.Item Comparative evaluation of algorithms for effective data leakage detection(2013) Kumar, A.; Goyal, A.; Kumar, A.; Chaudhary, N.K.; Kamath S․, S.S.Researchers have proposed several mechanisms to secure data from unauthorized use but there is very less work in the field of detecting and managing an authorized or trustworthy agent that has caused a data leak to some third party advertently or unknowingly. In this paper, we implement methods aimed at improving the odds of detecting such leakages when a distributer's sensitive data has been leaked by trustworthy agents and also to possibly identify the agent(s) that leaked the data. We also implement some data allocation strategies that can improve the probability of identifying leakages and can also be used to assess the likelihood of a leak at a particular agent assuming the fact that the data was not simply guessed by the third party where the leaked data set has been found. We also propose new allocation strategies that work on the basis of No-Wait model, i.e. agent does not need to wait for other agents' allocation and it is different from already proposed model that makes an agent wait for others. These methods do not rely on the alterations of the distributed data, but rather focus on minimizing the overlapping of the allocated data items to various agents, thus facilitating an exact determination of the guilty agent in a particular data leakage scenario. © 2013 IEEE.Item Performance evaluation of voltage stability index to assess steady state voltage collapse(Institute of Electrical and Electronics Engineers Inc., 2014) Prabhakar, P.; Kumar, A.The paper presents performance analysis of a comprehensive index to foresee voltage collapse at the weak load buses in the power system. A different approach for the assessment of voltage stability margins based on the P-Q-V curve technique and Thevenin's equivalent is proposed. A P-Q-V curve shows the periphery of the maximum real/reactive power and the minimum voltage magnitude in a three-dimensional diagram. Voltage stability region is the set of all feasible point below this curve. Thus the area of this region is an indicator of closeness to the voltage stability limit. As the index provides quantitative measurement in terms of the real and reactive power margins of a specified bus, it is more significant to identify weak nodes. Results on IEEE-14 bus system and IEEE-30 bus system are presented to illustrate the nature of the index AVSR and its effectiveness to predict voltage collapse. © 2014 IEEE.Item Multi-sink En-Route Filtering Mechanism for Wireless Sensor Networks(Springer Verlag service@springer.de, 2017) Kumar, A.; Pais, A.R.Wireless Sensor Networks (WSNs) are deployed in unattended environments and thus are prone to security compromises. Providing security and tamper resistant hardware to each node is also unrealistic. The compromised nodes can populate network with forged false reports which can cause false alarms and wrong decision making in networks. En-Route filtering is a popular method for filtering false reports in WSNs. Many such filtering techniques have been proposed for filtering false reports based on single sink. In this paper we propose a multi-sink en-route filtering mechanism, which reduces the overall energy consumption of the network. This is achieved by dividing the network into smaller networks and assigning a separate sink to each smaller network. This helps in reducing the hop count of genuine reports, saving lot of energy consumption. The proposed technique also decreases the key-exchange overhead maintaining the same filtering efficiency. The proposed technique also reduces the effect of selective forwarding attack in the network. The simulated results also support our claims and we are able to save up to 40% of energy consumption. © 2017, Springer Nature Singapore Pte Ltd.Item Smart multimode transmission for automobiles(American Society of Mechanical Engineers (ASME) infocentral@asme.org, 2017) Srinath, N.; Kumar, A.; Joladarashi, S.There are two basic types of transmissions- manual and automatic. While manual transmissions have greater transmission efficiency and better overall driving experience, it is difficult and not as easy to handle as automatic transmissions. Automatic transmissions make life a lot easier for the driver but are less efficient and laggard. So, the aim of this project is to take the best of both worlds and combine it in one, i.e. a transmission system that is capable of working as both a manual and an automatic transmission. For this, we plan to automate a regular manual transmission with a manual override option on both the clutch and the gearbox systems. Motors will be used to control the clutch and the changing of gears in the gearbox. In the manual mode, the motors will be operated by user input switches (clutch pedal and stick shift). In the automatic mode, the same motors will be controlled by a control algorithm based on various inputs like weight of the car, inclination, speed of the engine and the car etc. © 2017 ASME.Item Experimental studies on realization of underwater optical communication link(Institute of Electrical and Electronics Engineers Inc., 2017) Kumar, A.; Naik, R.P.; Shripathi Acharya, U.S.A comprehensive experimental setup for underwater optical communication (UWOC) is proposed in this paper. This UWOC real time setup provides an underwater communication link (using sea water) which is able to achieve reliable communication within a 3m long range. The minimum transmit power requirement for communication at a Bit Error Rate (BER) of 10-3 in the presence of turbulence (generated within the experimental setup) and stationary water has been determined. Two UWOC setups are implemented, first setup is designed by utilizing opaque PVC pipes and the second setup is designed by aquarium tank. These setups are used in conjunction with water jets and rotating plates (to bring about obstruction in the line of sight) to replicate conditions of underwater turbulence and blockage. This allows a realistic reconstruction of light wave propagation under the surface of the sea. Our proposed setup provides a platform for experimental studies on UWOC and convey the idea and it is helpful in the analysis of real time power budget required by the system. It provides a foundation for more comprehensive experimental platforms which will be designed to accurately mimic various disruptions that can be encountered with UWOC. The proposed UWOC helps in the development of constructive techniques that can mitigate the effects of the channel induced errors and ensure error free communication. © 2017 IEEE.Item Effect of wire electrode materials on die-corner accuracy for Wire Electrical Discharge Machining (WEDM) of Inconel 718(Elsevier Ltd, 2018) Kumar, A.; Abhishek, K.; Vivekananda, K.; MAITY, K.In present investigation to analyzed the effects of tool electrode on machinability of Inconel 718 using wire electrical discharge machining. An L16 orthogonal array has been used for experimentation by considering machine controllable factors (i.e. pulse on time, wire speed, flushing pressure and discharge current). The influence of the process parameters on the responses, such as, surface Roughness and corner error were studied. From the results, it has been observed that tool material has the significant nature on determining performance variables. It has been also observed that zinc coated brass wire have better performance on surface roughness and corner error than the uncoated brass wire. © 2017 Elsevier Ltd. All rights reserved.Item Optimisation of Machining Parameters using Grey Relation Analysis integrated with Harmony Search for Turning of AISI D2 Steel(Elsevier Ltd, 2018) Kumari, S.; Kumar, A.; Kumar Yadav, R.; Vivekananda, K.The objective of this study is to investigate the effects of different turning parameters like spindle speed (N), feed rate (f) and depth of cut (d) on different output performance parameters measures during dry turning of AISI D2 Steel using PVD coated carbide tool. An experiment has been conducted according to L9 orthogonal array in order to evaluate the turning performance characteristics like material removal rate (MRR) and surface roughness (Ra). An Effort was put to convert the multi responses into equivalent single response i.e. overall grey relation grade by using grey relational analysis. The present study also developed a mathematical model for overall grey relation grade in terms of the machining parameters. Here, improved version of the latest evolutionary algorithm such as harmony search (HS) has been implemented in order to evaluate the optimal machining condition. The results are also compared to genetic algorithm to validate the efficiency of aforesaid approach. © 2017 Elsevier Ltd. All rights reserved.