Performance Analysis of Path Loss Models at 1.8 GHz in an Indoor/Outdoor Environment to Verify Network Capacity and Coverage

Wireless Personal Communications - Cloud is an environment where the resources are outsourced as service to the cloud consumers based on their demand. The cloud providers follows pay as you go...     

Security-Performance Tradeoffs in a Class of Wireless Network Scenarios

There has been an extensive and widespread deployment of wireless local area networks (WLANs) for information access. The transmission, being of a broadcast nature, is vulnerable to security threats and hence, the aspect of security provisioning in these networks has assumed an important dimension. The security of the transmitted data over a wireless channel aims at protecting the data from unauthorized access. The objective is achieved by providing advanced security mechanisms. Implementing strong security mechanisms however, affects the throughput performance and increases the complexity of the communication system. In this paper, we investigate the security performance of a WLAN based on IEEE 802.11b/g/n standards on an experimental testbed in congested and uncongested networks in a single and multi-client environment. Experimental results are obtained for a layered security model encompassing nine security protocols in terms of throughput, response time, and encryption overhead. The performance impact of transmission control protocol and user datagram protocol traffic streams on secure wireless networks has also been studied. Through numerical results obtained from the testbed, we have presented quantitative and realistic findings for both security mechanisms as well as network performance. The tradeoff between the strength of the security protocol and the associated performance is analyzed through computer simulation results. The present real time analysis enables the network designers to make intelligent choices about the implementation of security features and the perceived network performance for a given application scenario.     

Optimization of the Security-Performance Tradeoff in RC4 Encryption Algorithm

Wireless Personal Communications - In this paper, we have investigated different vulnerabilities in RC4 and its enhanced variants to overcome the security attacks. It is established that in spite...     

Impact of L2 Triggering Time on Handover Performance for 4G Wireless Networks

4G wireless networks are based on All-IP architecture integrating cellular networks, Wireless local area networks, Worldwide Interoperability for Microwave Access, Wireless ad hoc networks, and Wireless Personal Area Networks etc. This makes seamless handover an important issue for users roaming among these networks. Anticipation of future events based on layer 2 (L2) trigger information is the basic principle of fast handover. It incurs higher signaling costs compared with the other protocols like Mobile IPv6 and Hierarchical Mobile IPv6. L2 trigger is based on fluctuating wireless channel states. Therefore, the handover anticipation using L2 trigger may sometimes be incorrect. Unnecessary buffer space is used for providing a smooth handover in the case of incorrect anticipation. Therefore, it is very important to analyze overhead costs and compare the performance of IP based handover protocols. This paper investigates the impact of L2 triggering time on the signaling cost, packet delivery cost, total overhead cost, and buffer space. Results show that Session to mobility ratio, L2 trigger time and number of subnets are determining parameters for optimizing handover performance.     

Data-driven handover optimization in small cell networks

Wireless Networks - Since the advent of 1G through 5G networks, telecommunication industry has gone through phenomenal transformation in the way we communicate, we work, and we socialize. In dense...     

Lightweight Cryptography: A Solution to Secure IoT

In Internet of Things (IoT), the massive connectivity of devices and enormous data on the air have made information susceptible to different type of attacks. Cryptographic algorithms are used to provide confidentiality and maintain the integrity of the information. But small size, limited computational capability, limited memory, and power resources of the devices make it difficult to use the resource intensive traditional cryptographic algorithms for information security. In this scenario it becomes impertinent to develop lightweight security schemes for IoT. A thorough study on the lightweight cryptography as a solution to the security problem of resource-constrained devices in IoT has been presented in this work. This paper is a comprehensive attempt to provide an in-depth and state of the art survey of available lightweight cryptographic primitives till 2019. In this paper 21 lightweight block ciphers, 19 lightweight stream ciphers, 9 lightweight hash functions and 5 variants of elliptic curve cryptography (ECC) has been discussed i.e. in total 54 LWC primitives are compared in their respective classes. The comparison of the ciphers has been carried out in terms of chip area, energy and power, hardware and software efficiency, throughput, latency and figure of merit (FoM). Based on the findings it can be observed that AES and ECC are the most suitable for used lightweight cryptographic primitives. Several open research problems in the field of lightweight cryptography have also been identified.

     

Network Selection Based on Weight Estimation of QoS Parameters in Heterogeneous Wireless Multimedia Networks

Network selection in a heterogeneous wireless environment is a major challenge to ensue seamless mobility across different radio air interfaces. To provide the desired quality of service for a given application in a multimedia environment, different parameters, including delay, bandwidth, packet loss and cost per byte, play an important role in network selection. In this paper, we present a novel algorithm for optimal network selection. A heterogeneous environment consisting of four networks, UMTS, WLAN, GPRS and WiMAX has been considered. We propose a network selection algorithm in which weight estimation for the representative set of the network attributes is computed using entropy and technique for order preference by similarity to ideal solution approach. The numerical results show that the proposed model can be effectively implemented to select the desired network in a heterogeneous environment employing triple-play services.     

WiMAX Network for Capacity and Coverage Assessment

This article represents the system performance and its operation stability of a fixed worldwide interoperability for microwave access network operating with point to multipoint technology. It provides broadband access in fixed locations for mixed environments in Greater Noida, UP, India. The Field measurement for its capacity and coverage are recorded simultaneously to optimize a network by raising customer premises equipment (CPE) antenna height. This process is not going to alter any technical parameters of a network. CPE antenna is a directional antenna facing towards base station to achieve optimum LOS reception. The net changes in RSS 10–17 dBm, DTR 512–1.8 Mbps, path loss exponent 0.5–0.9 and standard deviation of 1.2–2.3 were observed by raising CPE antenna height of 2–5 m above the prescribed height. The path loss exponents for different environments are obtained using least squares method based on measured data by MatLab statistics tool. Standard deviations of signal strength variability with distance are derived. Real coverage of a network is presented based upon path loss exponent and standard deviation. Our result suggest that, raising the height of CPE antenna can reduce transmitted power, there for reducing overall maintenance cost and system interference in future.     

A New Empirical Formula for Handover Rate in Microcellular Systems

In this paper, we propose a new empirical formula for handover rate as a function of base stations separation, standard deviation of shadow fading, path loss exponent, averaging distance, and correlation distance. The handover initiation algorithm is based on averaged signal strength measurements using relative signal strength with hysteresis margin approach. We generate the data through computer simulations for the average number of handovers referred to as handover rate, for the practical range of path loss exponent and standard deviation of shadow fading. The proposed formula provides for a practical design tool to optimize the handover initiation performance under varied propagation environments.     

An improved handover algorithm based on signal strength plus distance for interoperability in mobile cellular networks

In future generation mobile cellular systems, position location of mobile terminal is expected to be available. In this paper, we propose an initiation algorithm for intersystem handover based on the combination of position location of mobile terminal and the absolute signal strength thresholds. Global System for Mobile communication (GSM) and Universal Mobile Telecommunication Systems (UMTS) networks are considered for interworking. The proposed algorithm reduces the handover rate by around 50% and thus improves the network resource efficiency as compared to that based on signal strength thresholds only.