Vertical Handover In Heterogeneous Networks Research Articles

Vertical handover in heterogeneous networks using WDWWO algorithm with NN

ABSTRACT In heterogeneous networks, Vertical Handover (VH) plays a vital consequence of customer mobility as they have a high impact on networking performance like delay, throughput and call block probability. Even in the presence of various existing works, VH management exhibit certain drawbacks like method complexity, difficult network modelling and inaccurate handover. Thus, a hybrid methodology is proposed in this work which can provide accurate VH and considerable reduction in working complexity. Here, a combination of Deep Residual Neural (DRN) and Wind-Driven Water Wave Optimisation (WDWWO) is introduced to perform VH. Accurate prediction of Received Signal Strength (RSS) is a difficult task for mobile users while moving from one network to another. In order to tackle this situation, DRN is used with WDWWO based weight optimisation, hence the name Optimised DRN (ODRN). Almost every networking parameters like bandwidth, delay, throughput, velocity, BER, SNR, energy consumption, monetary cost and data traffic are included in ODRN modelling. The proposed work is implemented in NS2 platform and resultant performances like energy consumption, RSS, throughput, packet delivery ratio, packet loss, handover failure rate, algorithm convergence and latency are compared with conventional methods of D-TOPSIS, FIS-ENN and F-AHP.

Vertical Handover Analysis for Randomly Deployed Small Cells in Heterogeneous Networks

In this paper, we analyze vertical handovers in heterogeneous networks. Vertical handovers are an important ramification of user mobility in a heterogeneous wireless network since they directly impact network performance, such as throughput, packet delay, or call blocking probability. However, the study of vertical handovers faces many difficulties when it comes to analysis, including network modeling which is extremely complicated due to topology diversity. To tackle such analytic challenges, we propose a stochastic geometric analysis scheme on user mobility and small cell networks, in order to capture the impacts of different topologies. We derive a theoretical expression for the expected number of handovers that occur and a corresponding approximation. Our analysis shows that the number of vertical handovers is determined as a concave function of small cell radius r when given the small cell density. Via simulations our analysis is verified in various wireless environments.

Improving Modified Grey Relational Method for Vertical Handover in Heterogeneous Networks

With the advent of next-generation wireless network technologies, vertical handover has become indispensable to keep the mobile user always best connected (ABC) in a heterogeneous environment, especially the significant number of multimedia applications that require good quality of service (QoS) for users. To handle this issue, an improvement of modified Grey Relational Analysis (MGRA) to select the Always-Suitable-Connection (ASC) network has been proposed. Then, Fuzzy analytic hierarchy process (FAHP) method has been used to determine the weight of criteria. In order to validate our contribution, the proposed method called E-MGRA has been applied to obtain the ranking of suitable network. Finally, a simulation has been presented to demonstrate the performances of our developed approach to reduce the number of handovers compared to the classical method.

VIKOR MADM Based Optimization Method For Vertical Handover In Heterogeneous Networks

Optimum network selection is one of the major issues for vertical handover in heterogeneous networks so as to provide requisite quality of service (QoS) to the user. In this context, multiple attribute decision-making algorithms provide a promising solution. Normalization process used can play a vital role in selecting the most appropriate network during the handover process.In this work, vector normalized preferred performance based (V-VPP) normalization technique is proposed and applied to MADM based VIKOR algorithm. Performance of the proposed technique is analyzed extensively by varying QoS parameters and weighting methods for different traffic classes in a heterogeneous network The results obtained are compared with the available MAX, MAX-MIN and Vector normalization.The proposed method is also compared with the popular MADM algorithms. Performance of proposed method is quite optimistic in terms of lesser number of handovers, ranking abnormality, selection of appropriate network though with slight increase in handover latency in comparison to the available normalization methods.

WOA-NN: a decision algorithm for vertical handover in heterogeneous networks

The heterogeneous network of a 4th generation not always support better communication and mobility between the Wireless Access Networks. Hence, the vertical handoff is highly necessitated. This paper establishes vertical handover, which is context-aware in a heterogeneous environment with WiMax and WiFi. Successful handover results with the better determination of handover points. So, an Artificial Neural Network-based network model to understand the network characteristics is firstly developed. Under simulated environment, the Received Signal Strength (RSS) of the heterogeneous network is observed to construct the training library. The trained network predicts RSS for resolving the handover points in the heterogeneous network. To ensure precise learning of the neural network about the RSS network characteristics, a renowned Whale Optimization Algorithm (WOA) is developed. The performance of WOA-NN model is compared with the conventional Levenberg–Marquardt-Neural Network, Fire Fly-Neural Network, Particle Swarm Optimization-Neural Network and Grey Wolf Optimization-Neural Network through throughput, handover, predicted RSS and Mean Absolute Error analyses. The predicted RSS of the proposed WOA-NN-based network model seems nearly closer to the actual model, attaining effective handoff.

ARM-FPGA-based platform for reconfigurable wireless communication systems using partial reconfiguration

Today, wireless devices generally feature multiple radio access technologies (LTE, WIFI, WIMAX,...) to handle a rich variety of standards or technologies.These devices should be intelligent and autonomous enough in order to either reach a given level of performance or automatically select the best available wireless technology according to standards availability. On the hardware side, system on chip (SoC) devices integrate processors and field-programmable gate array (FPGA) logic fabrics on the same chip with fast inter-connection. This allows designing software/hardware systems and implementing new techniques and methodologies that greatly improve the performance of communication systems. In these devices, Dynamic partial reconfiguration (DPR) constitutes a well-known technique for reconfiguring only a specific area within the FPGA while other parts continue to operate independently. To evaluate when it is advantageous to perform DPR, adaptive techniques have been proposed. They consist in reconfiguring parts of the system automatically according to specific parameters. In this paper, an intelligent wireless communication system aiming at implementing an adaptive OFDM-based transmitter and performing a vertical handover in heterogeneous networks is presented. An unified physical layer for WIFI-WIMAX networks is also proposed. The system was implemented and tested on a ZedBoard which features a Xilinx Zynq-7000-SoC. The performance of the system is described, and simulation results are presented in order to validate the proposed architecture.

Vertical handover decision algorithm in heterogeneous wireless networks

With the recent progress in the area of cellular communication the issue of inter cells handover without dropping an ongoing connection with the base station has arisen. In this paper, the focus is on the performance of vertical handover. Various proposed interconnection architectures for vertical handover in heterogeneous networks were studied. Two different algorithms to make the decision on when and to which network perform a handover were considered. In the first of them the decision is based on the received signal strength (RSS). In the second one a fuzzy logic system that uses RSS, bandwidth, battery power and packet loss as the input parameters is proposed. The simulation results show that the algorithm based on fuzzy logic leads to a reduction of the number of handovers and a minimisation of the power consumption as compared to the first algorithm used here and the existing algorithms.

Simulation of Performance Execution Procedure to Improve Seamless Vertical Handover in Heterogeneous Networks

One challenge of wireless networks integration is the ubiquitous wireless access abilities which provide the seamless handover for any moving communication device between different types of technologies (3GPP and non-3GPP) such as Global System for Mobile Communication (GSM), Wireless Fidelity (Wi-Fi), Worldwide Interoperability for Microwave Access (WiMAX), Universal Mobile Telecommunications System (UMTS) and Long Term Evolution (LTE). This challenge is important as Mobile Users (MUs) are becoming increasingly demanding for services regardless of technological complexities associated with it. To fulfill these requirements for seamless Vertical Handover (VHO) two main interworking architectures have been proposed by European Telecommunication Standards Institute (ETSI) for integration between different types of technologies; namely, loose and tight coupling. On the other hand, Media Independent Handover IEEE 802.21 (MIH) is a framework which has been proposed by IEEE Group to provide seamless VHO between the aforementioned technologies by utilizing these interworking architectures to facilitate and complement their works. The paper presents the design and the simulation of a Mobile IPv4 (MIPv4) based procedure for loose coupling architecture with MIH to optimize performance in heterogeneous wireless networks. The simulation results show that the proposed procedure provides seamless VHO with minimal latency and zero packet loss ratio.

Soft Multi-Criteria Decision Algorithm for Vertical Handover in Heterogeneous Networks

Choosing or switching between heterogeneous networks according to the highest performance in terms of quality of service is largely inefficient in vertical handover. In fact a service may have unstable performance and require highly frequent vertical handover procedures. In this paper we consider the impact of statistical fluctuations of performance parameters (decision under risk) and propose a soft algorithm that exploits the statistical knowledge in order to reduce outage probability.

Soft handover mechanism based on RTP parallel transmission for mobile IPTV services

Mobile Internet Protocol Television (IPTV) provides users with multimedia content through wireless access technologies whenever they want and wherever they are. However, vertical handover in heterogeneous networks results in long interruption time and large packet loss rate, which poses a challenge for seamless mobile IPTV service. The existing solutions that make use of the heterogeneous access networks to transmit multimedia content have two drawbacks: high bandwidth consumption of the wireless networks and lots of packets loss when a user resides in the overlapped area of the boundary. To solve these issues, we propose a new soft handover mechanism, based on the IPTV server and the consumer electronic devices. The proposed Parallel Soft Handover (PSH) divides the Real-time Transport Protocol (RTP) packets according to the packet loss rates, and exploits different networks efficiently by using parallel transmission. Moreover, the selective retransmission for RTP packets is introduced to reduce the packet loss. Simulation results demonstrate that the PSH can reduce the packet loss rate, as well as obtain a more efficient use of the wireless bandwidth.

SAM: Secure Access of Media Independent Information Service with User Anonymity

Seamless handover across different access technologies is very important in the future wireless networks. To optimize vertical handover in heterogeneous networks, IEEE 802.21 standard defines Media Independent Handover (MIH) services. The MIH services can be a new target to attackers, which will be the main concern for equipment vendors and service providers. In this paper, we focus specifically on security of Media Independent Information Service (MIIS) and present a new access authentication scheme with user anonymity for MIIS. The protocol can be used to establish a secure channel between the mobile node and the information server. Security and performance of the protocol are also analyzed in this paper.

A receiver-based vertical handover mechanism for TCP congestion control

We propose and evaluate a vertical handover mechanism for TCP, based on receiver bandwidth delay product (BDP) measurement and congestion control using the receiver's advertised window. It addresses the negative impact of abrupt changes in link capacity and latency on TCP performance during make-before-break vertical handover in heterogeneous networks, enabling TCP to seamlessly adapt to new conditions. It resolves the problem of buffer overflow in a low capacity network on handover from a high capacity network, and the under-utilisation problem on handover in the reverse direction. All modifications are restricted to the mobile device, and the proposed technique is fully interoperable with existing TCP and mobile IP infrastructure. It maintains end-to-end semantics, supports IP security, and can be easily deployed