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Articles by S. Karthik
Total Records ( 33 ) for S. Karthik
  K.M. Maria John , Deepavenkatesan Venkatesan , S. Sandhiya , S. Karthik and Sampath Natarajan
  India has a diversity of medicinal plants. Most of them are used by the villagers against various diseases and are not revealed completely because of the secrecy maintained by them. Ormocarpum cochinchinense is found to be one among them which potentially shows good effect against bone fracture healing. The level of calcium in the plant is found to be one of the reasons for the bone healing effect. The scientific evidence of minerals present in the plant was important to prove the health effect of such medicinal plant. Since, the availability of O. cochinchinense is rare, an approach was made to study under in vitro condition. Callus induction was fast and reliable with Murashige and Skoog media containing 3 mg L-1 of kinetin and 1 mg L-1 of 2 4-D. The extract from leaves and callus was subjected to biomeneralization for calcite growth. The obtained calcite crystals were analysed with scanning electron microscope and the levels of calcium was quantified. Individual crystals were rod shaped and hexagonal in transactional view. When comparing the levels of minerals in the leaf and callus extract, it clearly indicated that the amount was high with leaf extract, but the variation was less. Results proved that the tissue culture of O. cochinchinense can be an alternative for biomeneralization of calcite crystals and also it can be used as a source for bone healing aid. The property of the plant in bone healing has to be ascertained by further experiments on animal models.
  S. Kannan , S. Karthik and V.P. Arunachalam
  Mobile Ad-hoc Networks (MANET) are self-organizing and self-configuring multihop wireless networks where the structure of the network changes dynamically. This is mainly due to the mobility of nodes. The nodes in the network not only acts as hosts but also as routers that route data to or from other nodes in network. In mobile ad-hoc networks, a routing procedure is always needed to find a path so as to forward the packets appropriately between the source and the destination. In a MANET, temporary link failures and route changes occur frequently. With the assumption that all packet losses are due to congestion, TCP performs poorly in such an environment. This study proposes a new mechanism called TASR, TCP-aware source routing which can improve TCP performance in wireless Ad-hoc networks. TASR adds a hold state to an existing routing protocol to reduce consecutive timeouts, retransmissions and out-of-ordered packets in TCP. In the simulation study, TASR achieves up to a 60% improvement in performance without requiring any TCP stacks in end systems to be modified.
  A. Gopi Saminathan and S. Karthik
  Data aggregation protocols are required in Wireless Sensor Networks (WSNs) to extend the network lifetime by reducing the energy consumption. The existing DAO-LEACH (Data Aggregation-Optimal LEACH) protocol for WSN is insecure and prone to false data injection. This is enhanced in terms of security and fault-tolerance based on Gracefully Degraded Data Aggregation (GDDA) to ensure the integrity of the aggregated data and Hybrid Layer User Authentication (HLUA) to ensure the confidentiality of the aggregated data. This data aggregation scheme rejects the false data from compromised and malfunctioning Sensor Nodes (SNs). HLUA consists of a combination of Secret Key Cryptography (SKC) Method such as MAC (Message Authentication Code) algorithm and Public Key Cryptography (PKC) Method such as Elliptic Curve Cryptography (ECC). MAC algorithm is used between the Cluster Heads (CHs) and SNs to fulfill lower power demand while ECC is applied for User Authentication (UA) between CHs and users. The enhanced DAO-LEACH protocol is resistant to security attacks such as replay attacks, node compromising attacks and impersonation attacks. It performs better in terms of energy consumption, number of alive nodes, End to End Delay (EED) and false data detection, compared to SCAR (Simple Cluster-based data Aggregation and Routing), ESPA (Energy-efficient Secure Path Algorithm), DKS-LEACH (Deterministic Key management based LEACH), SEDAN (Secure and Efficient Data Aggregation protocol for WSNs) and DAA (Data Aggregation and Authentication).
  R. Bharathiraja , S. Karthik and V.P. Arunachalam
  In Mobile Ad hoc Networks (MANETs), battery power is a limited resource and it is expected that battery technology is not likely to progress as fast as computing and communication technologies do. Hence, in order to lengthen the lifetime of batteries is an important issue which is supported by batteries only. But the existing power control techniques rarely consider the delay incurred in power estimation and connectivity of the network. Overhead problems are also caused by sending RTS packets. In order to solve the above problems, researchers propose to develop a power control MAC protocol for minimizing the power consumption and increasing the throughput in MANET. Initially, researchers assume that each node contains a neighbor set (NSET). Based upon the critical transmission range for connectivity, the nodes within the transmission range can be identified. Within the transmission range, the source node chooses the nodes with optimal initial transmission power value. These are stored in NSET to which the source can directly transmit the data with the selected optimal transmission power values. For the nodes beyond the transmission range, the power values of the intermediate nodes are also calculated and the source node sends data to the destination through nodes that has minimum transmission power value.
  G.M. Karthik , S. Karthik and Ramachandra V. Pujeri
  Since, extraction of frequent itemsets from transaction database is crucial to several data mining task such as association rule generation, so frequent itemset mining is one of the most important concepts in data mining. Frequent pattern mining has been widely used for discovering association and correlation among real data sets. However, discovering interesting correlation among frequent periodic patterns is more complicated and majority of them are unnecessary or uninformative. Researchers designed an algorithm that uses FP-tree for finding periodicity and correlation among multiple longest common substrings in time series data. Researchers introduce a parallel version of the algorithm called Frequent Correlated Periodic Pattern Mining algorithm which takes O(kN) for finding periodicity and tested on a coarse-grained multi-computer (BSP/CGM) Model with synthetic and real data sets. The experiment results show that algorithm is noise resilient, efficient and scalable than existing techniques.
  J. Shanthini and S. Karthik
  The grid computing is a flavor of distributed computing. It collects and coordinates resources across the administrative domain. The heterogeneous resources turns grid scheduling as challenging one as it has to deal resources with different resource behavior. So, the scheduler in grid environment has additional responsibilities than any other distributed environment scheduler. This research aims at minimizing the total tardiness of the schedule as it is directly proportionate to the cost of computation. A composite dispatching rule with heuristics to solve the grid scheduling problem is presented here. The first part of the study narrates about the composite dispatching rule I-ATC which is acombinationof Apparent Tardiness Cost (ATC) and Weighted Minimum Shortest Processing Time (WMSPT). I-ATC is an attempt to favor the early submitted jobs with along due date or with relatively low priority. These jobs may incur either early tardiness or lateness by the traditional dispatching rules. Later part of the study deals with the combination of I-ATC with Tabu search heuristics.
  R.M. Bhavadharini , S. Karthik and N. Karthikeyan
  Congestion in the network is a severe problem that affects the performance of MANET applications. When, a packet loss occurs in the wired medium, it clearly signs congestion in the network and suitable measures are taken to alleviate the effect of congestion. In a wireless environment, a packet can be lost for the factors such as wireless link error probability, link breakages, energy depletion, MAC contention fading and interference, etc. Due to various reasons contributing to the packet loss, Transmission Control Protocol (TCP) is unable to efficiently exploit the available network capacity in MANET. Across-layer congestion control algorithm with efficient Bandwidth Allocation and Dynamic Congestion Window Adaptation (CC-BADWA) is proposed in this study that uses TCP receiver’s prediction of bandwidth availability in the network and the receiver advertised window size back to the sender which then adjusts sender window. The timeout and the delayed acknowledgement can differently able the sender to predict the level of congestion in the network. When the acknowledgement is not received due to congestion in the network, the sender can estimate the transmission probability, adopt the dynamic congestion window size and transmit the packets. This improves the network throughput since, the sending rate is adjusted consistent to the currently prevailing network status. The bandwidth allocation uses the currently available bandwidth based on the present active connections and the route optimization proposed in this research selects the optimal path for data forwarding. The receiver’s timeliness helps to improve the network performance parameters throughput, end to end delay, packet delivery ratio of the existing method. The proposed algorithm is analyzed through ns 2 simulation tool.
  D. Prabakar , M. Marikkannan and S. Karthik
  The wireless sensor networks due to its invincible property finds its application in several areas. For all these applications, the energy utilization is the factor which determines the performance of the sensor networks. Routing of information and transmitting the same to the base station plays a vital role because the nodes are battery operated and the energy resources are scarce. The study proposes a novel protocol called Position Based Gossiping (PBG) for providing a solution for addressing the problems in gossiping technique. The proposed technique enhances the energy within the network and improves the lifetime of the network as compared to the conventional routing protocols. Moreover, the energy between the nodes are equalized which considerably enhances the lifetime of the network. As added the protocol minimizes the delay in transmission and loss of data packets.
  S. Raja Ranganathan , M. Marikkannan and S. Karthik
  In semantic web, the information flow obtained from different relations is certain and processing those data across the relations are not easy without proper understanding about the semantic mapping between them. It is a complex process to manually identify these mappings and it is not possible over the web. It is required to develop tools for supporting relation mapping for the success of the semantic web. A technique named sealant is designed for machine based learning for identifying the mappings. For two given catalogs, the percept in one relation is identified by sealant and it predicts the most common percepts in other catalogs. A probability based explanations for many resemblance measures are viewed using sealant which works well with all of them. Furthermore, the sealant employs different learning techniques each of which utilizes several information types either in the data occurrence or in the catalog framework of the relations. The matching precision can be enhanced by expanding the sealant for integrating sound understanding and domain restrictions into the matching process. The technique varies with its working ways using clearly explained resemblance perception and effective integration of several types of understanding. The sealant is expanded for identifying difficult mappings between the relations and explains the analysis for its effective utilization.
  R. Roopa Chandrika , N. Karthikeyan and S. Karthik
  Medical decision support system is a complex medical image analysis system that requires an efficient pattern classification tool that is easier to represent and to perform better classification of abnormalities present in medical images. Fuzzy Cognitive Map (FCM) is a simple, efficient cognitive tool used recently to model such complex and dynamic systems. FCM is integrated with medical decision support system that requires grading of suspicious tissues present in human body. FCM is used in this research to grade suspicious breast cancer cells with the texture properties extracted from digital mammograms. The map is constructed using the texture properties as its concepts and are interconnected based on the causal relationship among the concepts. The patterns or the features extracted from the digital mammogram are based on statistical measures suitable to distinguish between normal and abnormal tissues. GLCM (Gray Level Co-occurrence Matrix) and laws energy measures are statistical methods used in this research to obtain the textural features. The texture concepts used as input for the FCM tool have shown to classify the severity of abnormality present in digital mammograms better than the other classifiers that used training algorithms like neural network, decision trees, etc. The outcome of the automated reasoning of FCM is similar to the qualitative assessment tool used by the medical experts.
  C. Ram Kumar , S. Karthik and N. Karthikeyan
  Designing a sensor network as per the customer needs is the challenging task. While designing, we have to maintain some parameters like network life time, throughput, packet drop, congestion control, fairness and node energy. Congestion leads to the main issues in the network at both sender side and also in the receiver side. Congestion occurs due to more sensors, packet drop, receiving more packets than transmitting and buffer queue size. Here, we propose a fairness aware scheme with MRCCAP that shares the resource allocation, channel bandwidth. FACC protocol controls the congestion at base station which provides the support for QoS. Intermediate nodes are placed nearer to source and sink nodes to determine the flow rate, arrival time and queue size. Congestion avoidance algorithm deals with the ratio of the number of upstream nodes to the number of downstream nodes. In connection with gained weight buffer management with a probabilistic algorithm, it will provide efficient fairness and better network performance. The simulation results show that the proposed model provides better throughput, packet loss and network lifetime compared to the previous technique.
  M. Kavitha and S. Karthik
  Mobile Ad-hoc Network (MANET) is a network which allows mobile servers and clients to communicate in a dynamic Infrastructure. MANET is a fast and increasing region of study as it discovers and utilizes diversified applications, in which the information should be well structured for accessibility and data should be put together in the database. In such databases, the mobile peer stores and access the data functionality such as storage, manage and reports in the database. In this study, the challenges of data replicas in the mobile database are focused. Data replication mainly focuses on availability and reliability of data in the mobile nodes. Data replication concentrates on certain scenarios like frequency disconnection, node mobility, server network partition and power. In proposed method, a cluster based data replication technique for replicating data and to overcome the problems related to data management problems in MANET environment. The proposed approach has three phases; selfish node detection, formation of cluster and cluster head selection and finally, data distribution to the respective cluster head. By NS2 simulation, the performance of the proposed approach is observed to be efficient with improved data consistency with minimal overhead and delay.
  R. Roopa Chandrika, , N. Karthikeyan and S. Karthik
  Medical decision support system is a complex medical image analysis system that requires an efficient pattern classification tool that is easier to represent and to perform better classification of abnormalities present in medical images. Fuzzy Cognitive Map (FCM) is a simple, efficient cognitive tool used recently to model such complex and dynamic systems. FCM is integrated with medical decision support system that requires grading of suspicious tissues present in human body. FCM is used in this work to grade suspicious breast cancer cells with the texture properties extracted from digital mammograms. The map is constructed using the texture properties as its concepts and are interconnected based on the causal relationship among the concepts. The patterns or the features extracted from the digital mammogram are based on statistical measures suitable to distinguish between normal and abnormal tissues. GLCM (Gray Level Co-occurrence Matrix) and Laws energy measures are statistical methods used in this work to obtain the textural features. The texture concepts used as input for the FCM tool have shown to classify the severity of abnormality present in digital mammograms better than the other classifiers that used training algorithms like neural network, decision trees etc. The outcome of the automated reasoning of FCM is similar to the qualitative assessment tool used by the medical experts.
  I. Kala , N. Karthikeyan and S. Karthik
  In a disaster recovery scenario, there may be some static wireless nodes at special service providing locations such as a medical camps or helipads and the other mobile nodes such as mobile equipment carried by a rescue personal or any transport vehicle. This forms a Quasi MANET in which the mobile nodes periodically communicate to the static nodes with some critical priority. In Quasi MANET under consideration, there are some percentage of node which are not at all mobile throughout whole time of operation. This research work main scope is to design and implement a location based AODV routing model for Quasi MANET scenario and evaluate its performance with normal AODV routing protocol and other MANET routing protocols. Hence implemented a Region based Route Request Processing in AODV (RRRP_AODV) and compared its performance with normal AODV. The arrived result verifies the noteworthy progress in performance of RRRP_AODV.
  P. Ganesh Kumar , S. Karthik , R. Nidhya and R.M. Bhavadharini
  Real-road shortest-path finding algorithms involve large set of geographical data which include geo-tagged nodes and edges of the road network. Practical shortest path finding algorithms need minimized search-space for performing these computations by keeping these data in the computer’s conventional memory. The hierarchical pruning methods for minimizing the search-space to support real-road shortest algorithms are more suitable for connecting multiple cities and towns via highways. This study is to present a new suitable pruning method for intra-city shortest path finding, called elliptical pruning to bring the geo-tagged nodes and edges in to the memory for the subsequent shortest path finding process for the complex city road-transport networks.
  S. Kannan , T. Maragatham , S. Karthik and V.P. Arunachalam
  MANET has no clear line of defense so, it is accessible to both legitimate network users and malicious attackers. In the presence of malicious nodes, one of the main challenges in MANET is to design the robust security solution that can protect MANET from various routing attacks. Different mechanisms have been proposed using various cryptographic techniques to countermeasure the routing attacks against MANET. However, these mechanisms are not suitable for MANET resource constraints, i.e., limited bandwidth and battery power because they introduce heavy traffic load to exchange and verifying keys. In this study, the current security issues in MANET are investigated. Particularly, we have examined different routing attacks such as flooding, black hole, link spoofing attacks and some detection methods like profile-based detection, specification-based detection as well as existing solutions to protect MANET protocols.
  S. Kannan , S. Karthik and V.P. Arunachalam
  Mobile Ad-Hoc Network (MANET) is a collection of wireless mobile hosts forming a temporary network without the aid of any stand-alone infrastructure or centralized administration. Mobile ad-hoc networks are self-organizing and self-configuring multihop wireless networks where the structure of the network changes dynamically. This is mainly due to the mobility of nodes. The nodes in the network not only acts as hosts but also as routers that route data to or from other nodes in network. In mobile ad-hoc networks a routing procedure is always needed to find a path so as to forward the packets appropriately between the source and the destination. The main aim of any ad-hoc network routing protocol is to meet the challenges of the dynamically changing topology and establish a correct and an efficient communication path between any two nodes with minimum routing overhead and bandwidth consumption. The design problem of such a routing protocol is not simple since, an ad-hoc environment introduces new challenges that are not present in fixed networks. A number of routing protocols have been proposed for this purpose like Ad-Hoc On Demand Distance Vector (AODV), Dynamic Source Routing (DSR), Destination-Sequenced Distance Vector (DSDV). In this research, we study and compare the performance of the following three routing protocols AODV, DSR and DSDV.
  S. Kannan , T. Kalaikumaran , S. Karthik and V.P. Arunachalam
  A mobile ad-hoc network is a self configuring network connected by wireless links. No infrastructure or central administration is needed for these type of networks. Therefore, they are suitable only for temporary communication links. An important issue in computer network is to design the network in such a way to cope up with the speed required today. The task of routing the packets from a source to the particular destination in ad-hoc networks is hard because the network elements are mobile and there is no central control over the network elements. In any network, the data packets have to be routed to the destination with minimum loss, minimum delay and maximum packet delivery ratio. Therefore, there must be an efficient routing algorithm which satisfies all these quality of service requirements and it must also be robust and adaptive. The algorithm Multi Agent Ant Based Routing Algorithm is designed from the ACO framework, inspired by the behavior of biological ants. The algorithm consists of both reactive and proactive components. This technique increases node connectivity and decreases average end to end delay and increase packet delivery ratio. Since node connectivity increases, packet loss is reduced. The simulations are carried out by NS-2 and the results prove that Multi Agent Ant Based Routing Algorithm outperforms AntHocNet, AODV and DSR in terms of average end to end delay and packet delivery ratio.
  I. Kala , L.S. Jayashree and S. Karthik
  Topographic addressing of packets within mobile ad hoc networks enables modern applicability including hard perceptive-time agreement simulation in military training systems, geographic command and control functions in training and predicament communications and monetary messaging applications as well. The most extensible implementation of topographical addressing is via a Geocast protocol where nodes selectively rebroadcast packets based on provincial accord rules. Well-designed excommunication heuristics yield extensible topographic flooding that outplays surrogate geo addressing approaches. However, previous Geocast Routing implementations while effective, fall into two categories. Approaches based on flooding are inextensible due to the high load they achieve. Extensible approaches, on the other hand have difficulty in complex environments, lacking sufficient brilliance about the necessary directionality of packet flow. The present research defines a contemporary Geocast Routing heuristic, the Medial Range with Precedence (MR-P) Heuristic which both significantly improves on reliability of existing extensible Geocast Routings and yet also remains extensible as design complexity increases. This study describes the contemporary technique as well as an evaluation study comparing it to erstwhile approaches.
  S. Karthik , V.P. Arunachalam and T. Ravichandran
  Problem Statement: Denial of Service/Distributed Denial of Service (DoS/DDoS) attacks deny regular, internet services from being accessed by legitimate users, either by blocking the services completely, or by disturbing it completely, so as to cause customer baulking. Approach: Several traceback schemes were available to mitigate these attacks. Directional geographical traceback8 (DGT8), directional geographical trackback scheme, with 8 directions was one of them. Having a limited set of 8 directions, DGT8 may not work for routers with more than 8 interfaces. In this study, we had proposed Multi-DGT (DGT-16), a 16 directional geographical traceback scheme having all the advantages of DGT. The 16 directions, though not having exactly equal interface, had nearly equal measures and were identified using a novel scheme of Segment Direction Ratios (SDR). Results: The scheme of DGT16 SDR in directions D1-D16 in quadrant I-IV and DGT32 SDR in directions D1-D9 in quadrant I were examined. Conclusion: The implementation of DGT16, when a packet arrives at the victim, the geographical location of the attack router can be obtained from the data in the SDR subfields, regardless of the source IP address which may be incorrect or compromised.
  S. Karthik , S. Kannan , V.P. Arunachalam , T. Ravichandran and M.L. Valarmathi
  Denial of Service (DoS) attacks constitutes one of the major threats and among the hardest security problems in today's Internet. Of particular concern are Distributed Denial of Service (DDoS) attacks whose impact can be proportionally severe. With little or no advance warning, a DDoS attack can easily exhaust the computing and communication resources of its victim within a short period of time. Because of the seriousness of the problem many defense mechanisms have been proposed to combat these attacks. This study aims to provide an understanding of the existing attack methods, tools and defense mechanisms, so that a better understanding of DDoS attacks can be achieved. The goal of the study is to simulate an environment by extending NS2, setting attacking topology and traffic which can be used to evaluate and compare the methods of DDoS attacks and tools. Based on the simulation and evaluation results, more efficient and effective algorithms, techniques and procedures to combat these attacks may be developed.
  S. Kannan , T. Kalaikumaran , S. Karthik and V.P. Arunachalam
  Understanding and using the internet in worldwide is a challenging problem that is typically addressed by analyzing network traces. However, obtaining such traces presents its own set of challenges owing to either privacy concerns or to other operational difficulties. The key hypothesis of the research here is that most of the information needed to profile, the internet endpoints is already available around us on the web. We implement and deploy a Google-based profiling tool which accurately characterizes endpoint behaviour by collecting and strategically combining information freely available on the web. Unconstrained endpoint profiling approach is used to profile and classify the endpoints. The websites are classified and clustered based on the search hits which contain the hit text and URL. On querying, it matches the domain name and URL if it does not match then it verifies the key words. The key words in the web cache are clustered using Fuzzy C-means algorithm which enhances the speed of the search engine.
  S. Kannan , V.P. Arunachalam and S. Karthik
  Group communications are important in Mobile Ad hoc Networks (MANET). Multicast is an efficient method for implementing group communications. However, it is challenging to implement multicast packet forwarding over a dynamic topology. Researchers propose a novel Efficient Geographic Multicast Protocol (EGMP). A network wide zone based bi-directional tree is constructed to achieve more efficient multicast delivery. The position information is used to guide the zone structure building, multicast tree construction and multicast packet forwarding which efficiently reduces the overhead for route searching and tree structure maintenance. Several strategies have been proposed to further improve the efficiency of the protocol, for example introducing the concept of zone depth for building an optimal tree structure and integrating the location search of group members with the hierarchical group membership management. Finally, researchers design a scheme to handle empty zone problem faced by most routing protocols using a zone structure. The scalability and the efficiency of EGMP are evaluated through simulations. The simulation results demonstrate that EGMP has high packet delivery ratio and low control overhead and multicast group joining delay under all test scenarios and is scalable to both group size and network size. EGMP has significantly lower control overhead, data transmission overhead and multicast group joining delay.
  S. Karthik and S. Saravana Kuma
  This study research involves analyze and explore the study of the current state-of-the-art in parallel logic simulation including simultaneous simulation techniques. Functional verification, a tortuous and tedious task, refers to the verification of any logic design according to the specifications. It’s basically a cumbersome process due to the presence of an enormous number of test cases even for a simple logic design. Logic simulation is used to predict the behavior of digital circuits where the system components can vary from transistor level through the gate level to the behavioral level. Due to increased complexity, large designs, the time taken to test will also be long. To overcome this problem, parallel simulation was employed. Simulation based verification due to its ease in performing is widely used. As the name suggests it allows verifying the performance of various operations simultaneously, there by reducing the time to a considerable extent. So, this method is restored to achieve our goal. To verify our design, we chose a hardware platform named Zybo board (Zynq Z-7010-heterogeneous architecture). As the name suggests, it comprises of FPGA and a 650 MHz cortex-A9 ARM processor which expedites the testing process. We use Vivado tool for profiling, a process which helps one to know which portion of the function takes more time compared to other during the simulation. The portion which takes large time for simulation is port mapped to the FPGA while the rest is assigned to the processor.
  S. Balaji , S. Karthik and T.S. Balaji
  With increase in modernization day by day we expect all our work to be done in a simple way on its own with reduced human effort. Ultimately, it has led to advent of new technology called internet of things. IoT is an emerging technology which enables different devices to be interconnected between them and to communicate among them for various information exchange using internet. With world stepping into advanced communication technology new smart objects are getting evolved day by day with the applications of IoT. When IoT is implemented the main key role is played by a vital element called sensor. This study throws light on various sensors that are used in different application that makes use of IoT. This study also highlights various parameters of using sensors based on effectiveness, economic concern, efficiency, power consumption, availability, flexibility and compatibility.
  S. Kannan , Ishwarya , S. Karthik and V.P. Arunachalam
  In a mobile ad-hoc network, temporary link failures and route changes occur frequently. With the assumption that all packet losses are due to congestion, TCP performs poorly in such an environment. This study proposes a new mechanism called TASR, TCP-aware source routing which can improve TCP performance in wireless ad-hoc networks. TASR adds a hold state to an existing routing protocol to reduce consecutive timeouts, retransmissions and out-of-ordered packets in TCP. In the simulation study, TASR achieves up to a 60% improvement in performance without requiring any TCP stacks in end systems to be modified.
  S. Kannan , T. Kalaikumaran , S. Karthik and V.P. Arunachalam
  Routing problems in mobile ad-hoc networks have been receiving attention in the last few years. Most of the proposed routing protocols concentrate on finding and maintaining routes in the face of changing topology caused by mobility or other environmental changes. The power aware routing protocols and the topology control algorithms have been developed to address the issue of limited energy reserve of the nodes in ad-hoc networks. In this study, an algorithm has been designed and it has been enhanced with the AODV protocol for transmitting high density data over the ad-hoc network. This enhanced protocol is named as EL-AODV protocol. Enabling the high density data over, ad-hoc networks is more exigent as the links are highly error-prone and go down frequently. The challenge in data transmission over ad-hoc networks is due to the nomadic nature of the host and identifying a dynamic routing protocol that efficiently finds a stable route between mobile nodes. The simulation results show that the pro-posed scheme shows better performance when compared with existing protocol.
  S. Kannan , V.P. Arunachalam and S. Karthik
  In the context of wireless sensor networks, nodes have limited energy and forward messages of different importance. An algorithmic technique called band-based directional broadcast is used to control the direction of broadcasts that originate from the sensor nodes. A key challenge is how to gather the sensor data in a manner that is energy efficient with respect to the sensor nodes that serve as sources of the sensor data. In the research, an optimal selective forwarding scheme is introduced in order to save energy in wireless sensor networks. The goal is to direct each broadcast of sensor data toward the mobile sink, thus reducing costly forwarding of sensor data packets. The technique is studied by simulations that consider energy consumption and data deliverability.
  S. Kannan , T. Kalaikumaran , S. Karthik and V.P. Arunachalam
  MANET has no clear line of defense so, it is accessible to both legitimate network users and malicious attackers. In the presence of malicious nodes, one of the main challenges in MANET is to design the robust security solution that can protect MANET from various routing attacks. Different mechanisms have been proposed using various cryptographic techniques to countermeasure the routing attacks against MANET. However, these mechanisms are not suitable for MANET resource constraints, i.e., limited bandwidth and battery power because they introduce heavy traffic load to exchange and verifying keys. In this study, the current security issues in MANET are investigated. Particularly, the researchers have examined different routing attacks such as flooding, black hole, link spoofing attacks and some detection methods like profile-based detection specification-based detection as well as existing solutions to protect MANET protocols.
  S. Karthik , A. Kowshika and C. Maheswari
  Discovering and maintaining routes between nodes are one of the biggest challenges in MANETs the ultimate goal of the MANET community is to provide a set of standardized protocols that can be both robust and scalable. This study proposes routing protocols based on the heading direction angle + Number of hops, Number of hops + heading direction angle, the best heading direction angle route. The first one is designed to calculate the angle direction and when the angles are the same take the best hop count. The second one is designed to calculate the best hop count and when the hops counts are the same take the best angle direction. The last one is designed to calculate the average of all heading direction angles in the route and find the best route from the source to the destination. The researchers measure the performance of the proposed approach by comparing it with the well known On-Demand (reactive) routing protocol (AODV).
  S. Karthik , N. Gugha Priya , T. Maragatham , B. Chellaprabha and M. Marikannan
  The goal of steganography is to avoid drawing suspicion to the transmission of a hidden message. If suspicion is raised, steganography may fail. The success of steganography depends on the secrecy of the action. If steganography is detected, the system will fail but data security depends on the robustness of the applied algorithm. In this study, the secret message are compress and encrypt it by the receiver’s public key along with the stego key and embed both messages in a carrier using an embedding algorithm. The stego-image is the result we get by running the algorithm you select on the message (file to hide) and cover (image). It can be saved into BMP or PNG format. The reason that it can only be saved in these formats is because they are lossless, there is no information lost as part of the file formatting.
  S. Kannan , S. Karthik and V.P. Arunachalam
  Mobile Ad-hoc Networks (MANET) are self-organizing and self-configuring multihop wireless networks where the structure of the network changes dynamically. This is mainly due to the mobility of nodes. The nodes in the network not only acts as hosts but also as routers that route data to or from other nodes in network. In mobile ad-hoc networks a routing procedure is always needed to find a path so as to forward the packets appropriately between the source and the destination. The main aim of any ad-hoc network routing protocol is to meet the challenges of the dynamically changing topology and establish a correct and an efficient communication path between any two nodes with minimum routing overhead and bandwidth consumption. The design problem of such a routing protocol is not simple since an ad-hoc environment introduces new challenges that are not present in fixed networks. A number of routing protocols have been proposed for this purpose like Ad-Hoc On Demand Distance Vector (AODV), Dynamic Source Routing (DSR), Destination Sequenced Distance Vector (DSDV). In this study, we study and compare the performance of the following three routing protocols AODV, DSR and DSDV.
  S. Kannan , V.P. Arunachalam and S. Karthik
  This research investigates distributed clustering scheme and proposes an Ad hoc On demand Distance Vector (AODV) routing protocol for Delay-Tolerant Mobile Networks (DTMNs). The basic idea is to distributively group mobile nodes with similar mobility pattern into a cluster which can then interchangeably share their resources (such as buffer space) for overhead reduction and load balancing, aiming to achieve efficient and scalable routing in DTMN. An ad hoc network is self-organizing and adaptive. Networks are formed on the fly, devices can leave and join the network during its lifetime, devices can be mobile within the network, the network as a whole may be mobile and the network can be deformed on the fly. Devices in mobile ad hoc networks should be able to detect the presence of other devices and perform the necessary set-up to facilitate communications and the sharing of data and services. Due to the lack of continuous communications among mobile nodes and possible errors in the estimation of nodal contact probability, convergence and stability become major challenges in distributed clustering in DTMN. Extensive simulations are carried out to evaluate the end to end delay and overhead of the proposed Ad hoc On demand Distance Vector (AODV) routing protocol.
 
 
 
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