Earticle

False report injection attacks and false vote injection attacks can be perpetrated easily by malicious attackers on the application layer in a wireless sensor network. These attacks drain the lifetime of the sensor nodes and prevent the forwarding of legitimate reports in the sensor network. A probabilistic voting-based filtering scheme (PVFS) was proposed in order to drop these two types of attacks simultaneously in intermediate cluster heads. Before transmitting a report, the scheme selects verification nodes within the intermediate cluster nodes to detect false votes attached from compromised nodes. In this paper, we propose a method to improve the detection power and energy savings by using a blacklist in every cluster head. The blacklist stores each compromised node ID and false key. The performance of the proposed method against these attacks was evaluated and compared to that of PVFS. The simulation results reveal that the proposed method enhances the average energy consumption and security level of each cluster head as compared with PVFS.

Vertical Handoff (VHO) is a major concern for different heterogeneous networks. VHO can be user requested or based on some criteria already designed by the researcher of that particular algorithm. It’s about switching from one network to another while maintaining the session. Numerous algorithms have been given in this respect. In this paper a new implementable procedure has been introduced. It’s a mechanism, in which multiple users having access to different networks can execute the VHO, in such a manner that when the handoff takes place it do not interrupt any ongoing call or data session. A server and clients have been created. A call was established and it was maintained by Session Initiation Protocol during switching from one network to another. By employing a technique called IP Assignment VHO was carried out successfully. The proposed scenario has made implementation of VHO practically possible.

In this paper, we present three novel input buffer schemes for systems with network on chip. These proposed buffer schemes are based on a self-compacting buffer, and can provide larger available buffer space per physical channel for communicating applications. These schemes outperform existing approaches. DAMQshr has similar performance using only sixty three percent of the buffer size that is used in traditional implementation for NoCs. DAMQmin provides an excellent technique to optimize buffer management, and provides a good throughput when the network has a larger load. In addition, they also have better utilization of the available buffer space.

The mobile networks play a vital role in the information and communication technology. There are two kinds of mobility supported by mobile networks such as host mobility and network mobility. The enhancement of Quality of Service (QoS) in NEtwork MObility (NEMO) environment is more complex than host mobility environment. One of the complexities in NEMO environment is routing of packets. The routing algorithms play a significant role in enhancing QoS. This necessitates looking into the weaknesses of existing routing algorithms. Based on the weaknesses, we have already proposed a Delay-Sensitive Routing for NEMO (DSRNEMO) to enhance the QoS in NEMO environment with respect to delay parameter. The objectives of this paper are to derive a mathematical model for DSRNEMO and to simulate the operations of DSRNEMO. The outcome of the mathematical model and simulation results show that the DSRNEMO gives better results than the existing algorithm, NEMO. Ultimately, this paper contributes to enhance the QoS in mobile networks.

For the activeness and autonomy of a sensor network, a mobile agent's role that enables a code itself to move between sensor nodes or migrate to a server and carry out a given task is important. Since such a migration method of the mobile agent is a factor that affects the overall performance of the entire distributed system, it is necessary to find efficient migration methods of the mobile agent within the sensor network and to collect and store data related to various components (server, sink and sensor node) of the sensor network, thereby providing consistent naming services. For this, in this paper, we design an improved MetaTable that is divided into MetaData where information on the sensor data server is stored and SubMetaData where various types of information on sink nodes and data on sensor nodes connected with the sink nodes is stored. Also, we propose the efficient method of naming service on the sensor network by using the proposed MetaTable. The migration of mobile agent depends on the information of MetaData and SubMetaData referred to, and the reliability of the migration information is determined by mutual cooperation between a naming agent and each sensor server. And, we implement the migration method of mobile agent by using the naming service via meta_data generation method, migration list and priority. For the verification of validity and guarantee of applicability of the proposed method, we performed experiments on the migrations of the mobile agent and active rule execution through the mutual relations between agents by using meta_data on the components of the sensor network.

Quality of broadband connectivity over a residential power line is dependent on its topology; which is very different from twisted pair copper used in telephony. In this paper methods to estimate the topology of a power line are investigated. A two step procedure comprising of a set of correlation time domain Reflectometry (CTDR) measurements based on Single Ended Loop Testing (SELT) and an initial topology estimate as a first step, followed by a comparison with frequency domain Reflectometry (FDR) measurement as a second step to finally ascertain the power line topology. A set of codes with complementary autocorrelation property is used for probing the line. The number of bridge taps (BTs) in a power line is large and spaced closely; hence multiple applications of CTDR from different sockets are carried out to understand tap positions close to the measuring socket. An analysis of the measurements from multiple CTDR applications is then used to generate a first estimate of the complete power line topology. In the second step a FDR signature of the loop is computed and compared with the frequency domain Reflectometry (FDR) measurement in a mean squared sense to validate the findings. The CTDR and FDR use existing functional blocks of any DSL modem and do not need any additional equipment for measurement. This method is tested for a wide range of power line topologies with multiple bridge taps. The transfer characteristic of the estimated power line loop topology is derived using transmission matrix method and the channel capacity estimated.

Considering the rapid development of Internet of Things, this paper tries to solve its integrated management problem. The aim of this paper is then to introduce new-generation network management standardization that is NETCONF and propose the use of RESTful Web Services from the viewpoint of lightweight requirements for integrated management of Internet of Things. Using the proposed approach, this paper discusses the definitions of management operations based on NETCONF over HTTP for integrated management of Internet of Things. In the end of this paper, two typical integrated management scenarios for Internet of Things are provided, in order to validate the feasibility of the proposed approach.

The streaming service over conventional HTTP has received only one kind of screen quality image which is provided by server. The contents which were provided by the streaming service provider to the general users have been only high definition image. Also, the contents business units who used to establish existing streaming service can provide various streaming services through web modulation. In conventional streaming service, simple method of one content is transmitted to client was used, whereas streaming technology without blockage suiting to network interference and communication environment at real time using dynamic adaptive streaming over HTTP was implemented in this study In this study, it was also focused on the validation of streaming service which conventionally used to provide with one original image by developing and testing the images adaptively played with BITRATE suiting to network status through converting original image into BITRATE of several screen quality to provide streaming service without blockage even under limited network environment.

Mobility prediction algorithm is the significant aspect to improve QoS (Quality of Service) for heterogeneous wireless networks because it decreases handoff latency and preserves resources in arriving cells for users. Since existing mobility prediction algorithms based on GPS (Global Positioning System) often suffer from low prediction accuracy for complex and irregular trajectory, this paper combines support vector regression with local prediction to propose a novel mobility prediction algorithms based on local support vector regression (LSVR) to overcome above deficiency. Simulation results show that LSVR algorithm achieves high prediction accuracy for a size of historical data in three typical mobile scenes.

Power control is a burning issue in modern wireless communication systems. Specially, in systems based on Code Division Multiple Access (CDMA) technology used in Universal Mobile Telecommunication System (UMTS), power control is adopted for maximizing the overall capacity of wireless system and battery life of mobiles terminals. A number of adaptive methods for power control in UMTS for different outdoor environments were reported in literature, but the focus on power control for indoor environments remained negligible. So this paper aims to perform a comparative analysis of above mentioned power control techniques for different indoor propagation models. Performance evaluation was carried out on the basis of overall spectral efficiency (SE) and power control error (PCE).

LEACH series protocols are low energy consumption adaptive clustering routing protocols in wireless sensor networks which were firstly proposed by MIT scholars. Considering the disadvantages of the TDMA mechanism which has been used in LEACH series protocols, such as long time delay and high energy consumption, an improved routing protocol based on OVSF code in clustered sensor networks is proposed. Facilitated by its orthogonality and incoherence, the transmission can be realized based on the demands of the node, but not the time slot, during which the member node has to transmit data to the cluster heads. The simulation results show that the proposed OVSF code based routing protocol greatly reduces delay and energy consumption compared with TDMA based protocols.