Handover Approaches Research Articles

Handover algorithm based on Bayesian-optimized LSTM and multi-attribute decision making for heterogeneous networks

Heterogeneous networks (HetNets) which can satisfy the diverse requirements of future terminal tasks through providing different network access services for terminals, have emerged as a vital technology for the development of next-generation networks. However, frequent access to different networks often leads to high handover delay and handover failure, resulting in a degradation of user experience. Therefore, maintaining seamless network connectivity has become a challenging problem for applications with high real-time and reliability requirements in HetNets. To address this problem, we propose a handover algorithm based on Bayesian-optimized Long Short-Term Memory (BO-LSTM) and multiple attribute decision making (HO-BLM) to reduce handover latency and failure, ensuring seamless network connectivity. To reduce handover delay, we designed a handover decision prediction algorithm based on BO-LSTM to trigger handover in advance by predicting the network state of users in the future. Additionally, we propose a preselection mechanism based on current network status to further reduce the calculation delay. Moreover, a multi-attribute decision making (MADM)-based selection approach is designed to select the best alternative network for a specific user, where the utility value of the best alternative network is calculated by weighing the users’ preferences for network parameters of different business types and the actual status of the candidate networks. Simulation results show that the proposed algorithm decreases the handover failure by up to 42.1% and the handover delay by up to 68% compared with traditional handover approaches.

Survey on Handover Techniques for Heterogeneous Mobile Networks

This paper presents an overview of existing techniques of Handover in Heterogeneous Mobile Networks. It gives an overview of the mobility management processes and mainly focuses on decision-making approaches. The literature has reported many problems with seamless support for mobility management techniques. Failures in the Handover operation are caused by frequent disconnections and ineffective seamless Handovers. Therefore, to provide customers with an acceptable Quality of Service, Heterogeneous Mobile Networks must have an effective mobility management system that allows many wireless networks to collaborate. A single parameter, two or more extra factors, or a mix of both are used by several mobile controlled Handovers to assess the policy choice. In this paper, We have covered many Handover approaches, as well as advancements that have been achieved throughout time. Almost all of the Handover Techniques over the previous ten years have been covered. Based on the many Advantages and Limitations, we have tabulated all the Handover procedures. The paper will be beneficial to emerging specialists in the sector.

5G handover issues and techniques for vehicular communications

<span lang="EN-US">Vehicular communication is gaining popularity, and seamless handover is critical to maintaining a stable and uninterrupted network connection between vehicles and roadside units. This paper investigates the advancements in handover approaches in vehicular networks, with a specific focus on 5G technology. Vehicular Ad-hoc Networks (VANETs) face challenges due to high mobility, dynamic network topology, and frequent information exchange. The paper discusses handover issues in 5G VANET environments, such as too-late and too-early handovers, wrong handover decisions, and unnecessary handovers. It also explores key performance indicators (KPIs) used in handover evaluation. The advancements in handover approaches presented in this paper pave the way for enhanced connectivity and communication management in 5G VANETs, contributing to the development of safer and more efficient intelligent transportation systems.</span>

User-Centric Cooperative Transmissions-Enabled Handover for Ultra-Dense Networks

The user-centric cooperative transmission provides a compelling way to alleviate frequent handovers caused by an ever-increasing number of randomly deployed base stations (BSs) in ultra-dense networks (UDNs). This paper proposes a new user-centric cooperative transmissions-based handover scheme, i.e., the group-cell handover (GCHO) scheme, with the aim of reducing the handover rate in UDNs. In the proposed scheme, the boundary of the cooperating cluster depends on the distance among the user equipment (UE) and cooperating BSs. The new scheme captures the dynamicity and irregularity of the cooperating cluster topology resulting from randomly distributed BSs. Based on stochastic-geometry tools where BSs locations are modeled as the Poison point process (PPP), we derive an analytical expression of the handover rate for the UE with an arbitrary movement trajectory. Furthermore, a GCHO skipping (GCHO-S) scheme is proposed to minimize the handover cost, i.e., the percentage of time wasted in handover signaling in user-centric cooperative transmissions scenarios. The numerical results show that the GCHO scheme decreases the handover rate by 42.3% and 72.7% compared with the traditional single BS association and fixed-region cooperative network topology handover approaches, respectively. Moreover, under the same group-cell size and constant velocity, the GCHO-S scheme diminishes the handover cost by 50% against the GCHO scheme.

Analytical Review and Study on Various Vertical Handover Management Technologies in 5G Heterogeneous Network

In recent mobile networks, due to the huge number of subscribers, the traffic may occur rapidly; therefore, it is complex to guarantee the accurate operation of the network. On the other hand, the Fifth generation (5G) network plays a vital role in the handover mechanism. Handover management is a prominent issue in 5G heterogeneous networks. Therefore, the Handover approach relocates the connection between the user equipment and the consequent terminal from one network to another. Furthermore, the handover approaches manage each active connection for the user equipment. This survey offers an extensive analysis of 50 research papers based on existing handover approaches in the 5G heterogeneous network. Finally, existing methods considering conventional vertical handover management strategies are elaborated to improve devising effective vertical handover management strategies. Moreover, the possible future research directions in attaining efficient vertical handover management in a 5G heterogeneous network are elaborated.

Evaluation of a Paper-Based Checklist versus an Electronic Handover Tool Based on the Situation Background Assessment Recommendation (SBAR) Concept in Patients after Surgery for Congenital Heart Disease.

(1) Background: we compare a new SBAR based electronic handover tool versus a paper-based checklist for handover in a pediatric intensive care unit (PICU). (2) Methods: this is a randomized, observational study of 40 electronic vs. 40 paper checklist handovers after pediatric cardiac surgery, with a 48 items checklist for comparison of reporting frequencies and notification of disturbances and noise. PICU staff satisfaction was evaluated by a 12-item questionnaire. (3) Results: in 14 out of 40 cases, there were problems with data processing (incomplete or no data processing). Some item groups (e.g., hemodynamics) were consistently reported at higher frequencies than other groups. Items not specifically asked for did not get reported. Some items, automatically processed in the SBAR handover page, did not get reported. Many handovers suffered a noisy and distracting atmosphere. There was no difference in staff satisfaction between the two handover approaches. Nurses were highly unsatisfied with the general approach by which the handover was performed. (4) Conclusions: human error appears to be a main factor for unreliable data processing. Software is still too complicated, and multitasking is a stressful and error prone event. Handover is a complex task with many factors required for a successful completion.

A quality improvement project to improve handover in the integrated assessment liaison team

BackgroundEfficient handovers are integral to patient care. Challenges to handover for liaison psychiatry included high patient and staff turnover and varied handover approaches across the multidisciplinary team (MDT).MethodMDT focus groups and questionnaires explored change ideas. PDSA cycles were used to design a structured handover.We aimed to:Reduce handover time to 30 minutes.Improve communication using the SBAR tool.Implement a multidisciplinary teaching schedule in the time saved.Daily measures:Handover timingTeam Satisfaction (Individuals ranked handover as ‘good’, ‘average’, or ‘poor’)Weekly measures:Semi-qualitative questionnaires triangulated areas for improvement.Emails, posters and team meetings provided team feedback regarding QI progress.ResultA structured twice-daily handover format incorporating SBAR, allocated handover coordinators and documentation was created. Weekly MDT teaching sessions were developed.Over 4 weeks, ‘good’ handover ratings increased from 22% to 65%; ‘poor’ ratings decreased from 25% to 8%. Mean handover time decreased from 37 minutes to 28.5.The team viewed SBAR as a positive efficiency-promoting tool. MDT teaching improved team communication and confidence. Documentation is an area to improve.ConclusionStructured handover has promoted efficiency and effective information-sharing amongst the liaison psychiatry team.Interdisciplinary teaching can promote inclusive team feeling and encourage confidence across the MDT.

A new handover protocol between old age admission and rehab wards

AimsEfficient handovers are integral to patient care. Challenges to handover for wards include high patient turnover and varied handover approaches between wards, as well as admissions out of hours. Patients on Old Age Wards often have multiple comorbidities and can deteriorate rapidly without coordinated care. Our focus was on improving handover of patients transferred between the Old Age Admissions Ward and Rehabilitation Ward. We aimed to create a ward handover protocol to improve compliance with documenting a pretransfer plan and ensure there was an 80% compliance with completing this plan within 3 months.MethodAn MDT discussion took place in order to explore change ideas. Questionnaires were filled out post implementation of protocol. A handover proforma was designed to capture important patient data and continuing plans. A PDSA cycle was designed to deliver a structured handover.Per patient measures were collected including: whether a handover took place, recording of current medical and psychiatric issues, documentation of plan and was the plan put into action or reviewed.MDT feedback was collected on satisfaction with the protocol and handover process using open questions and Likert scale.ResultPrior to the establishment of the proforma there was no verbal or written handover between wards. In 28% of cases prior to the intervention, blood results were checked and medication reviews took place within the timeframe written in the patient's notes. A proforma was initiated and used for 93% of patient handovers between wards. Blood results were checked according to the planned timeframe in 86% of cases. Where the handover proforma took place, 100% of patients had a medications review. Qualitative detail revealed that key patient appointments such as MRI Brain scans and important plans such as fluid restriction limits were missed before implementing the protocol. Aftewards complex patient plans were recorded and implemented accordingly.Questionnaire feedback was positive and MDT found the proforma to be helpful and to improve patient safety.ConclusionThe team viewed the new handover pathway as a positive patient safety tool. Compliance with completing the protocol in the longer term and maintaining change is an area for ongoing improvement.

The effectiveness of “I PASS The BATON” model in improving nursing handover at a university hospital in Vietnam

Nursing handover is an important process in hospital care where information and responsibilities are transferred from one nurse to another to ensure continuity of care and safety of patients. However, evidence of the effectiveness of using standardized nursing handover approaches, particularly in resource-limited countries, is scarce. This study was conducted in order to evaluate the change in handover practice through the “I PASS the BATON” model in a university hospital in Vietnam and identify factors contributing to the effectiveness of this model. We provided handover training for nurses in the Emergency Department using the “I PASS the BATON” model and evaluated their application right after the course and one month after the course. The consistency of the handover skill among participating nurses remained high one month after applying the model in the routine care at the hospital. Overall, the mean score achieved after training was high and remained unchanged after one month. However, significant and marginally significant improvement was found in some components one month after the course including the Action and Timing. In contrast, the Next component decreased over time. Evaluation of nurses’ perceptions about the model were assessed using the Health Belief Model which revealed that perceived susceptibility and seriousness were at the moderate level and significantly decreased after one month. In contrast, perceived benefits and barriers were at a high level and remained unchanged after one month. The “I PASS the BATON” model was effective in improving nurses’ handover skills and practices.

Efficient Handover Approach in 5G Mobile Networks

Femtocell technology has improved cellular coverage and capacity allowing the provision of rich and interactive communication services in current mobile networks. However, this technology suffers from several drawbacks including; increased interference and packet loss, frequent handovers, and high energy consumption. This paper presents a new handover management approach to overcome performance limitations linked to handover taking place at dense femtocell environments. RSSI of Base Station (BS), mobile user’s movement direction, and BS available capacity are factors used in this work to improve handover decision while sustaining perceived network performance. In addition, in order to reduce the complexity and delay of handover process, the proposed approach has redefined handover major phases including; preparation, decision and execution phases. A densely deployed simulated environment representing heterogeneous 4G and 5G architecture was implemented to evaluate the proposed approach. The simulation environment consists of three paths, each path represents a different network and mobility condition including BS distribution, obstacles, UE movement direction and distance. Results confirmed that the proposed handover approach reported an improved performance in terms of handover delay and number of unnecessary handovers. The average number of handovers occurred during all simulation scenarios was 3, also the average handover delay achieved was (55.15 ms). The number of handovers were decreased 30% and handover delay was reduced more than 10 ms comparing to conventional handover approaches such RSS-based. Hence, an improved adoption of handover management into femotocell environment.

Handover analysis of openflow-based mobile networks with distributed control plane

A centralized controller approach in Software-Defined Networking (SDN) creates problems related to scalability and performance degradation. These problems are the main reason for introducing an architecture of logically distributed controllers. Ensuring the continuity of a user's ongoing session and reducing the interruption time during a handover, is one of the major challenges in today's modern mobile networks. In this paper, we propose a novel analytical approach to model the delay introduced by the handover-related OpenFlow signaling messages in SDN networks using multiple controllers. The analytical model is verified using extensive simulations. The results show that high probability of Packet-in messages causes rapid degradation of network performance. Similarly, by increasing the number of controllers, the number of synchronization messages increases, thus impacting the packet service time. Our findings can facilitate the design of delay-constrained handover approaches in a mobile network with a target system throughput.

Vertical Handover Study on 4G Category Vs 5G Category for 3GPP Generation Mobile Systems and Non-3GPP Wireless Networks

Nowadays, wireless communication technologies have become an integral part of people’s daily life and businesses all over the world. Due to the rapid increase in the number of the Mobile Users (MUs) who demand the service of communicating via wireless access networks, the wireless communication technologies have evolved from the first generation to the fifth generation. The Next Generation Wireless Systems (NGWSs) consists of heterogeneous wireless access networks of 3GPP generation mobile Systems (e.g., UMTS, LTE) and non-3GPP wireless networks (e.g., WiFi, WiMAX), where MUs can access these technologies and services using a single device. This paper presents a study for Vertical Handover (VHO) approaches of 3GPP and non-3GPP proposed in the literature and classifies them into two categories for which their characteristics are discussed.

Efficient Management and Fast Handovers in Software Defined Wireless Networks Using UAVs

Compared to traditional networking, SDN has better controllability and visibility for network components, which enable better management by using the common controller. In this article, the standard architecture of SDN is enhanced to utilize UAVs as on-demand forwarding switches. The proposed approach can achieve efficient management and fast handovers by decreasing the handover latency, E2E delay, and signaling overheads. The illustrated scenarios will help in understanding the impact of existing handover approaches in the next generation wireless networks, especially the upcoming 5G, which includes small cells, UAVs, UEs, and so on. The simulation study shows that scenarios with both UAVs and small cells perform better than scenarios with only small cells. The results in this article show that the proposed SDNbased handover scenarios perform better than the existing 4G-LTE handover for UAVs.

Energy-Efficient Vertical Handover Parameters, Classification and Solutions over Wireless Heterogeneous Networks: A Comprehensive Survey

In the last few decades, the popularity of wireless networks has been growing dramatically for both home and business networking. Nowadays, smart mobile devices equipped with various wireless networking interfaces are used to access the Internet, communicate, socialize and handle short or long-term businesses. As these devices rely on their limited batteries, energy-efficiency has become one of the major issues in both academia and industry. Due to terminal mobility, the variety of radio access technologies and the necessity of connecting to the Internet anytime and anywhere, energy-efficient handover process within the wireless heterogeneous networks has sparked remarkable attention in recent years. In this context, this paper first addresses the impact of specific information (local, network-assisted, QoS-related, user preferences, etc.) received remotely or locally on the energy efficiency as well as the impact of vertical handover phases, and methods. It presents energy-centric state-of-the-art vertical handover approaches and their impact on energy efficiency. The paper also discusses the recommendations on possible energy gains at different stages of the vertical handover process.

Multi-Attribute Decision Making Handover Algorithm for Wireless Body Area Networks

In this paper, we tackle the Wireless Body area Network (WBAN) handover issue where a mobile patient has to select at any time the best access technology according to multiple criteria. We particularly focus on the decision schemes and investigate the Multi-Attribute Decision Making (MADM) methods. The fundamental objective of the MADM methods is to determine among a finite set of alternatives the optimal one. Therefore, we propose a Multi-Attribute Decision Making Handover Algorithm (MADMHA) which helps patient’s mobile terminal to dynamically select the best network by providing a ranking order between the list of available candidates. It is a seamless handover approach that guarantees continuous connectivity with respect to the QoS requirements of the WBAN generated traffic types, network history and user preference. Simulation results prove the efficiency of our proposed approach versus the Received Signal Strength Indicator (RSSI) and Data Rate (DR) based handover approaches. Indeed, compared to these latters, MADMHA significantly reduces the packet overhead and the number of handover, while limiting the packet loss ratio.

Enabling vehicular mobility in city-wide IEEE 802.11 networks through predictive handovers

The increasing number of IEEE 802.11 networks deployed worldwide gives mobile users the possibility of experiencing high-speed wireless access on the move. Moreover, the high density of these deployments in urban areas make IEEE 802.11 a suitable access technology for moving vehicles. However, in order to provide a seamless access to vehicles, the transition between Access Points (APs) must be quick and reliable. The main bottleneck of existing handover mechanisms is the long AP scanning process, which only provides a snapshot of the available networks at a given location, impacting the handover decision on moving vehicles. To overcome this limitation, we propose coper, a context-based predictive handover mechanism that considers vehicle's trajectory, road topology, and network deployment information to decide the best handover location and candidate access points. We validate with real experiments in a city-wide 802.11 network and show that coper can provide better average signal strength, data rate, and connected time than other existing handover approaches.

Regressive Prediction Approach to Vertical Handover in Fourth Generation Wireless Networks

The over increasing demand for deployment of wireless access networks has made wireless mobile devices to face so many challenges in choosing the best suitable network from a set of available access networks. Some of the weighty issues in 4G wireless networks are fastness and seamlessness in handover process. This paper therefore, proposes a handover technique based on movement prediction in wireless mobile (WiMAX and LTE-A) environment. The technique enables the system to predict signal quality between the UE and Radio Base Stations (RBS)/Access Points (APs) in two different networks. Prediction is achieved by employing the Markov Decision Process Model (MDPM) where the movement of the UE is dynamically estimated and averaged to keep track of the signal strength of mobile users. With the help of the prediction, layer-3 handover activities are able to occur prior to layer-2 handover, and therefore, total handover latency can be reduced. The performances of various handover approaches influenced by different metrics (mobility velocities) were evaluated. The results presented demonstrate good accuracy the proposed method was able to achieve in predicting the next signal level by reducing the total handover latency.

Vertical Handover Solutions Over LTE-Advanced Wireless Networks: An Overview

The convergence of multitude radio access networks forming a cluster of seamless heterogeneous wireless environment has made the wireless communication industry meet the paradigm of always best connected, where various mobile devices are able to access numerous types of applications and services. However, achieving such landmarks could not be possible without difficulties which this paper tries to highlight some of the technical challenges underlying seamless vertical handover. It provides a general overview of the mobility management process including a brief on multi-homing mobility protocol and focuses on vertical handover decision making techniques, hi ghlighting some radio interface standar and analysed some handover approaches. The paper proposes fast intelligent inter-layer network selection as a new handover approach to select the best network among the candidate networks, where Quality of Service, handover delay and improved data bit rates are set to be achieved.

Intra-Mobility Support Solutions for Healthcare Wireless Sensor Networks–Handover Issues

At present, several solutions are available for monitoring patient health using body sensors. In hospitals, healthcare wireless sensor networks (HWSNs) offer support to access these sensors to allow for continuous patient monitoring. To improve the quality-of-life of the hospitalized patients, it is important to let them walk around the monitored area. This ability brings several challenges to HWSNs with mobility support. Because of the crucial importance of the sensed parameters, the HWSNs must be in continuous communication with the body sensors. The connection between body sensors and a HWSN is performed through an access point. Indoor communications are limited in terms of signal propagation and, therefore, several access points to cover large areas are deployed. To maintain the sensors' accessibility, these should frequently change their point of attachment by performing a mechanism known as a handover. Handover mechanisms are able to support the intra-mobility of sensors in networks within the same domain. This paper surveys the most recent intra-mobility solutions with special focus on handover approaches that can be used in HWSNs. An in depth review of the related literature is performed in order to present the state of the art on this paper, to discuss the available solutions, and to point out open issues for further research.

An Optimized Mechanism for Adaptive and Dynamic Policy Based Handover in Clustered Manet

On-going revolution in ever-improving wireless communication enforces the necessity of a self configuring, rapidly deployable and infrastructure less network. MANET is such an autonomous wireless network that meets the requirements. At the same time MANET’s random behavior and absence of any central intelligence to gather unambiguous knowledge about user contexts complexes QoS maintenance and hampers proper utilization of network resources resulting into unnecessary handovers. In past, few policy driven handover approaches have been proposed for MANET but none of them explores a comprehensive policy design. Therefore in this paper we propose an adaptive and optimized policy based handover mechanism which is based on explicitly designed policies like load balancing, service discovery and next hop selection .Efficient procedures for these policies are also explored .This work predicts the high time of handover need on the basis of application specific needs of individual freely roaming mobile nodes, avoiding unnecessary handovers and provides efficient handover procedure with optimized resource consumption, reduced latency and interruption time.