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Modeling and Analysis of Handover Algorithms
Abstract
Handover between various networks or cells of the same network is an important problem faced by mobile nodes. With so many handover algorithms available, how to evaluate and select them become critical. A mathematical model for wrong decision probability and handover probability is given in this paper such that they can be used as criteria to evaluate handover algorithms. Explicit expressions for these two parameters are vigorously studied via a general bandwidth based handover algorithm. A WDP predication based handover algorithm is also proposed to improve the handover performance.
... Handoff algorithms based on the RSS does not meet the requirement of upper layer applications where traffic is more and sensitive with time so handoff is implemented based on the bandwidth as the main parameter. Handoff algorithm based on bandwidth for two and three heterogeneous wireless networks are available in the literature [10], [11]. In this paper, Probability of handoff analysis is done for multiple HetNets (two, three, four and five) based on handover algorithm by considering bandwidth as 20MHz which is suitable for evaluating the performance of current wireless HetNets such as integration of LTE and WiMAX, LTE to Wi-Fi etc. From the results, the handover probability comparative analysis is carried out for multiple (two, three, four and five) HetNets. ...
... The analytical model of handover for two wireless networks as shown in Figure. 1 (a) is explained by C. Chi, et.al. [10]. Consider, the probability of handover for three networks i.e. ...
... Table 3. Probability of handover (PH) vs bandwidth (B) for constant threshold (Gth)=9,10,11 at traffic load ( )=8 ...
p>The need of wireless services increasing day by day due to the advancements in the field of wireless technology towards 5G for instant transferring the mails, messages and video calling without any interruption. In LTE and 5G wireless networks, major task is to provide seamless connection anywhere, anytime when the user may roam among Heterogeneous Wireless Networks (HetNets). To achieve proper mobility management among HetNets, handoff or hadover is required. Handover Probability is one of the metric to estimate the handover performance, which is a probability of Mobile Node to handover the present connection from the current base station to another base station or enode B. In this paper, handoff probability analysis is done for multiple HetNets based on Handover Algorithm. To estimate this algorithm, bandwidth is considered as one of the key parameter. A comparative analysis of handover probability for two, three, four and five HetNets has been performed. The results can demonstrate that the variation of handover probability with respect to traffic load, threshold and bandwidth. It is observed that, as the number of wireless networks increases handover probability slightly increases with traffic load. These results are more significant to estimate further wrong decision handovers based on that Quality of Service (QoS) is evaluated in practical HetNets such as integration of LTE, Wi-Fi and WiMAX etc. </p
... If the number free channels become less than 10 at the time transfer, then the decision was incorrect and it is called as unsuccessful handover. In other words, the criterion on which the handover has happened is no longer true when the actual handover too place, resulting in unsuccessful handover.The successful and unsuccessful handover probabilities are computed for a 2 node wireless network based on the bandwidth [3]. The basic definition of the successful and unsuccessful handovers, description of the nomenclatures etc, can be found in the ref [3]. ...
... In other words, the criterion on which the handover has happened is no longer true when the actual handover too place, resulting in unsuccessful handover.The successful and unsuccessful handover probabilities are computed for a 2 node wireless network based on the bandwidth [3]. The basic definition of the successful and unsuccessful handovers, description of the nomenclatures etc, can be found in the ref [3]. Akhila et.al extended the 2 node wireless network model to 3 node network model for bandwidth and received signal strength criteria [4][5][6]. ...
... The above models did not derive the approach to arrive at the parameters to achieve highest successful handover rates. Also the models in [2][3][4][5][6][7][8] did not focus on a WPAN kind of applications where one has to chose models having varying number of nodes.In this work, an attempt is made to address the issues of variable number or access points available in a WPAN for the handover to take place. Also, a generalized probability model has been developing to compute the probabilities in a WPAN environment. ...
... The disadvantage of these algorithms is lack of robust analytical model in the structure. This gap in the measurement of performance of algorithms necessitated the concept of the Wrong decision probability model [6]. This model measures the number of incorrect decisions made by the handover algorithms irrespective of the kind of decision criteria used for the handover. ...
... In this work, an improvement is made to the wrong decision model developed in ref [6]. Four different states of the mobile node [21] are considered in this work. ...
... The models proposed by Chi et. al [6] have only two network nodes with just one state, i.e. cooperative state of mobile node. ...
... The Real-Time Maude model provides an expressive tool to perform reachability analysis and the checking of temporal logic in WSN systems. On the other hand, the modeling and analysis of hand-off algorithms for cellular communication network are constructed by employing various modeling formalisms [5,8]. The modeling of fast hand-off algorithms for microcellular network is derived by using the local averaging method [5]. ...
... The performance metrics of the fast hand-off algorithms and the necessary conditions of cellular structures are formulated by using the model construction. In another approach, the modeling technique is employed to evaluate the hand-off algorithms for cellular network [8]. In this case, the model is constructed based on the estimation of Wrong Decision Probability (WDP) and the hand-off probability [8]. ...
... In another approach, the modeling technique is employed to evaluate the hand-off algorithms for cellular network [8]. In this case, the model is constructed based on the estimation of Wrong Decision Probability (WDP) and the hand-off probability [8]. In the image processing systems, the modeling and analysis of signals are performed by designing the sliding window algorithms. ...
In general, the modeling and analysis of algorithmic systems involve discrete structural elements. However, the modeling and analysis of recursive algorithmic systems can be done in the form of differential equation following control theoretic approaches. In this paper, the modeling and analysis of generalized algorithmic systems are proposed based on heuristics along with z-domain formulation in order to determine the stability of the systems. The recursive algorithmic systems are analyzed in the form of differential equation for asymptotic analysis. The biplane structure is employed for determining the boundary of the recursions, stability and, oscillatory behaviour. This paper illustrates that biplane structural model can compute the convergence of complex recursive algorithmic systems through periodic perturbation.
... Handover probability modeling is gaining popularity and vertical handover analytical methods based on handover probability are explained in [8][9]. Wrong decision probability modeling for vertical handover decision is presented in [10]. In ref [10] authors adopted the wrong decision probability as a metric for vertical handover decision based on network parameters and one such metric used in this case was bandwidth. ...
... Wrong decision probability modeling for vertical handover decision is presented in [10]. In ref [10] authors adopted the wrong decision probability as a metric for vertical handover decision based on network parameters and one such metric used in this case was bandwidth. Wrong decision probability is also assumed as a performance metric for the proposed algorithms. ...
... Handover ProbabilityFig.10 shows the improvement (reduction) in the wrong decision probability by changing the network model from 2 node network to 3 node network. ...
In this work, probability equations are derived for the five node networks and the probabilities are computed for unnecessary handover, missing handover and wrong decisions. Wrong decision probability is the summation of unnecessary and missing handover probabilities. Also, the handover probability is computed for the bandwidths up to 20. The modeling is based on the five state Morkov chain model. Simulations are carried out for the different decision times from D=1 to D=5 ms. The simulation results for the five node network model is compared with the two node and three node network models.
... Available bandwidth for a mobile terminal is the main criterion in this group [2,6,16]. In some algorithms, both bandwidth and RSS information are used in the decision process [3,17]. ...
... However these algorithms may also introduce ping-pong effect. To reduce the unnecessary handovers a Wrong Decision Probability (WDP) prediction based algorithm [2] is proposed. In this method the probability of unnecessary and missing hanovers is combined and WDP is calculated. ...
... ii) At the point when a data transmission reservation is carried out or when a channel is accessible, a handoff appeal can be completed. [7], [8]. ...
... Chi, C., Cai, X., Hao, R., & Liu, F., [8] Proposed a VHD algorithm based on the wrong decision probability (WDP). The WDP is computed by consolidating the likelihood of unnecessary and missing handovers. ...
... In[13]authors concluded that unnecessary handover (UHO) leads to ping-pong effect and brings in low network throughput, longer handoff delay and high dropping probability. In[14], authors used WDP model to evaluate the VHO decision, based on BW as performance metric using two network model. WDP was calculated based on UHP and MHP metric. ...
... Definitions for these four states can be found in ref.[20][21][22]. The five node network model proposed by[14,18]has all the nodes in cooperative state and is referred to as single state model and is referred to as four state model in[20][21][22], considering the other three states. ...
... In case of group mobility (e.g., a group of passengers equipped with mobile terminals on board a bus or train) whereby a group of mobile terminals enter into the service area of a heterogeneous network, the selection (by each mobile terminal) of a suitable RAT is a crucial decision. Such RAT selection is not supposed to be done in a random way, but rather on the basis of certain criteria such as radio signal strength (RSS), quality of service (QoS) parameters [1,2], quality of experience (QoE) criteria [3,4], individual consideration and contextual information [5], handoff cost in the uncertainty of QoS parameters [6], and signal to interference plus noise ratio (SINR) parameter [7]. However, most state of the art RAT selection mechanisms and schemes do not consider the impact introduced by decisions of other mobile terminals. ...
... Each mobile user is a player that has to pick one system network among the two available networks. 2 , a i,3 : : : , a i,m g i2N : is the set of strategies of each player i. In our scenario, each player i has two strategies: ...
Traditional vertical handover schemes postulate that vertical handovers (VHOs) of users come on an individual basis. This enables users to know previously the decision already made by other users, and then the choice will be accordingly made. However, in case of group mobility, almost all VHO decisions of all users, in a given group (e.g., passengers on board a bus or a train equipped with smart phones or laptops), will be made at the same time. This concept is called group vertical handover (GVHO). When all VHO decisions of a large number of users are made at the same time, the system performance may degrade and network congestion may occur. In this paper, we propose two fully decentralized algorithms for network access selection, and that is based on the concept of congestion game to resolve the problem of network congestion in group mobility scenarios. Two learning algorithms, dubbed Sastry Algorithm and Q-Learning Algorithm, are envisioned. Each one of these algorithms helps mobile users in a group to reach the nash equilibrium in a stochastic environment. The nash equilibrium represents a fair and efficient solution according to which each mobile user is connected to a single network and has no intention to change his decision to improve his throughput. This shall help resolve the problem of network congestion caused by GVHO. Simulation results validate the proposed algorithms and show their efficiency in achieving convergence, even at a slower pace. To achieve fast convergence, we also propose a heuristic method inspired from simulated annealing and incorporated in a hybrid learning algorithm to speed up convergence time and maintain efficient solutions. The simulation results also show the adaptability of our hybrid algorithm with decreasing step size-simulated annealing (DSS-SA) for high mobility group scenario. Copyright © 2015 John Wiley & Sons, Ltd.
... E-mail: yyao@stevens.edu the received signal strength [1], bandwidth [3]. Some other studies consider a combination of several factors as one criterion. ...
... Received signal strength (RSS) based criteria [1] [2] effectively reflects the distance information between the user and the network access point, which is important for mobile equipments to keep seamless connections. Authors in [3] and [4] adopt the available bandwidth as the main criterion for network selection. Overall load among heterogeneous wireless networks can also be a criterion in [5]. ...
We focus on the network selection problem in heterogeneous wireless networks. Many traditional approaches select the best network according to quality of service (QoS) related
criteria, which neglects diverse user demands. We aim to select networks maximizing the quality of experience (QoE) of users. When the availability and dynamics of network state information are considered, most of the existing approaches can not make effective selection decisions since they are vulnerable to the uncertainty in network state information. To address this issue, we introduce the idea of online learning for network selection. In this paper, we formulate the network selection problem as a continuous time multi-armed bandit (CT-MAB) problem. A traffic-aware online network selection algorithm (ONES) is designed to match typical traffic types of users with respective optimal networks in terms of QoE. Moreover, we found that the correlation among multiple traffic network selections can be exploited to improve the learning capability. This motivates us to
propose another two more efficient algorithms: decoupled online network selection algorithm (D-ONES) and virtual multiplexing ONES (VM-ONES). Simulation results demonstrate that our online network selection algorithms attain around 10% gain
in QoE reward rate over non learning-based algorithms and learning based algorithms without QoE considerations.
... To reduce the unnecessary handovers a Wrong Decision Probability (WDP) prediction based algorithm [123] is proposed. In this method, the probability of unnecessary and missing handovers is combined and WDP is calculated. ...
The thesis topic is a part of the global interest in wireless vehicular networks. Over the past decade, the number of road accidents has increased quickly with the growth of the automotive sector. Statistics have demonstrated that the high number of accidents on the road is primarily due to the high traffic density and the lack of information about other drivers' decisions. Recent studies have shown the importance of vehicular communications, which allow the exchange of real-time traffic safety information between vehicles and thus contribute to accidents avoidance.Through vehicular communication, known as vehicle-to-everything (V2X), which includes vehicle-to-vehicle (V2V) and vehicle-to-infrastructure, vehicles can exchange road safety and traffic management messages with low latency. Platoon formation is considered an interactive option that can improve V2X communication and ensure more safety. The vehicle platoon is defined as a group of vehicles following each other, moving in a straight line with a very short inter-vehicle space. Several vehicle platoon formation strategies have been defined in order to manage the platoon's lifetime and stability. However, none of these strategies has taken into account traffic congestion and speed constraints.The first objective of our work is to propose a new platoon formation algorithm called speed platoon splitting (SPS) where vehicles are grouped according to their destination (the leading vehicle has the farthest destination and the latest vehicle has the nearest destination). The main purpose of SPS is to target alleviating congestion by using a ticket pool and classify platoons according to their velocity in two different lanes. Performance analysis shows that SPS provides platoon stability and reduces highway congestion.V2X communications can be achieved via radio frequency (RF) technologies, especially the 802.11p standard. However, due to the accelerated growth in the number of devices, this technology suffers from several problems such as high latency and channel congestion. An alternative communication solution is provided by visible light communication (VLC). VLC is the usage of visible light as a wireless data transmission technique. VLC reduces complexity and cost, enables high precision positioning and increases network scalability and security.The second objective of this thesis tackles the performance of VLC in V2V among the platoon members. For this purpose, we considered two mathematical models validated by simulations for two different scenarios (we have taken an M/M/1 and an M/GI/1 queues for the first and the second scenarios respectively). The performance evaluations present a detailed study of the VLC in the presence of disruptive vehicles and they are used to derive computations of the Quality of Service parameters. The main conclusion drawn is that VLC technology is considered an efficient technique but it is affected by disruptive vehicles.The third objective of the thesis focuses on proposing a mechanism for vertical handover (VHO) between VLC and RF technologies. This objective is composed of two parts, the first one is based on the threshold value to make a vertical handover decision or by using machine learning techniques. The second part is to choose the appropriate technology after VHO using the utility function or the cooperative game.Throughout the thesis, the performance evaluation of the VLC is based on mathematical modelling. Moreover, the simulation is performed to validate this mathematical modelling.
... Hence, these algorithms use machine learning techniques to formulate the VHD process [37] [38]. Artificial neural network is also used where a comprehensive set of input-desired output patterns are available [34] [39]. A real-time learning processes may also be applied which can analyze and modify their own structure to improve the efficiency. ...
Internet of Things (IoT) is ubiquitous, including objects or devices communicating through heterogenous wireless networks. One of the major challenges in mobile IoT is an efficient vertical handover decision (VHD) technique between heterogenous networks for seamless connectivity with constrained resources. The conventional VHD approach is mainly based on received signal strength (RSS). The approach is inefficient for vertical handover, since it always selects the target network with the strongest signal without taking into consideration of factors such as quality of service (QoS), cost, delay, etc. In this paper, we present a hybrid approach by integrating the multi-criteria based VHD (MCVHD) technique and an algorithm based on fuzzy logic for efficient VHD among Wi-Fi, Radio and Satellite networks. The MCVHD provides a lightweight solution that aims to achieving seamless connectivity for mobile IoT Edge Gateway over a set of heterogeneous networks. The proposed solution is evaluated in real time using a testbed containing real IoT devices. Further, the testbed is integrated with lightweight and efficient software techniques, e.g., microservices, containers, broker, and Edge/Cloud techniques. The experimental results show that the proposed approach is suitable for an IoT environment and it outperforms the conventional RSS Quality based VHD by minimizing handover failures, unnecessary handovers, handover time and cost of service.
... The Signal Strong First (SSF) is the most widely used traditional approach, which performs the selection by comparing the RSSI of the current network with available adjacent networks [1]. Other approaches based on a single criterion use the available bandwidth [7], load in the network [8], or Signal to Interference Noise Ratio (SINR) [9] to select the network. As these approaches only use one criterion, they ignore important information, leading to throughput drops, unnecessary handovers, and even service disruption [6,10,11]. ...
Network selection plays a pivotal role in ensuring efficient handover management. Some existing approaches for network selection may use one criterion, such as RSSI (Received Signal Strength Indicator) or SINR (Signal to Interference Noise Ratio). However, these approaches are reactive and may lead to incorrect decisions due to the limited information. Other multi-criteria-based approaches use techniques, such as statistical mathematics, heuristics methods, and neural networks, to optimize the network selection. However, these approaches have shortcomings related to their computational complexity and the unnecessary and frequent handovers. This paper introduces NetSel-RF, a multi-criteria model, based on supervised learning, for network selection in WiFi networks. Here, we describe the created dataset, the data preparation and the evaluation of diverse supervised learning techniques (Random Forest, Support Vector Machine, Adaptive Random Forest, Hoeffding Adaptive Tree, and Hoedding Tree techniques). Our evaluation results show that Random Forest outperforms other algorithms in terms of its accuracy and Matthews correlation coefficient. Additionally, NetSel-RF performs better than the Signal Strong First approach and behaves similarly to the Analytic Hierarchy Process-Technique for Order Preferences by Similarity to the Ideal Solution (AHP-TOPSIS) approach in terms of the number of handovers and throughput drops. Unlike the latter, NetSel-RF is proactive and therefore is more efficient regarding Quality of Services (QoS) and Quality of Experience (QoE) since the end-devices perform the handover before the network link quality degrades.
... An effort is made in this research work to determine the total unsuccessful probability considering both unnecessary handover probability and blocking probability for a three-network system. The literature for the methods to estimate the unnecessary handover can be found from [21]- [23]. ...
In this paper, a novel method to estimate the unsuccessful probability
is proposed by combining the unnecessary probability and the blocking
probability. The Unnecessary probability is the probability when the
mobile node is unnecessarily handed over and the blocking probability
is the one when the network is not able to assign the channel to the
mobile now. A new design of new channel assignment method for
cognitive radio system is presented. The first fit method and the random
assignment methods are also implemented for the cognitive radio
application as a baseline. The PU and SU call blocking are modeled for
all the three methods. It is shown that advantages of first fit method
and the random assignment methods are combined into the new
method, namely, selective assignment method. Simulation are
conducted for the various network parameters like number of channels,
number of links, load on each link, percentage of the PU versus SU
calls etc. It is shown that selective assignment method yields better
results than that of the first fit method and the random assignment
methods. Finally, the blocking probabilities are combined with the
unnecessary handover probabilities of a three-node network to
determine the unsuccessful handover probabilities of the first fit,
random assignment and selective assignment methods.
... In [10] proposed WDP(Wrong Decision Probability) handover algorithm examines the unnecessary handover probability and missing handover probability. The performance of the traditional bandwidth-based algorithm is also studied and compared with WDP. ...
... It is achieved by switching between technologies when current connected network does not serve requirement. There are various vertical handoff techniques received signal strength based scheme [18], bandwidth based [19] , cost based [20] and combination based. ...
... It is achieved by switching between technologies when current connected network does not serve requirement. There are various vertical handoff techniques received signal strength based scheme [18], bandwidth based [19] , cost based [20] and combination based. ...
Development in wireless technology is mainly
because of constraint of bandwidth and coverage issues .The
concept of all time connected i.e. the possibility of being
connected everywhere any time was born with the
development of Vertical Handoff (VHO) between networks.
An efficient e-health system uses multiple technologies
together to provide better health care delivery. This paper
gives the overview of the different technologies used and the
VHO techniques used for an effective and efficient e-health
application implementation.
... The paradigm of 4G networks are designed to provide superior performance in terms of quality of service, data transmission speed , reduced latency, high security , support integrated services and also to provide higher bandwidth , higher data rate and low authentication overhead with seamless connectivity. 1 The 4G networks are envisioned towards convergence / integration of various access radio access networks. 4G is referred as MAGIC-Mobile Multimedia, Anytime anywhere, Global mobility support, Integrated wireless solution and Customized personal service. ...
Handover is the key procedure in wireless networks to provide required qual ity of service to the users during mobility Handover. As the current scenario of wireless communication comprises of heterogeneity in architecture, application and radio access technologies concentrating on vertical handover becomes important to provide continuous communication and ubiquitous coverage .This paper provides comprehensive survey of the vertical handover, decision technique and parameter used for making proper handover in horizontal and vertical handover . The recent handover schemes are discussed and classified which varies based on concepts and the adopted schemes. A Fuzzy based decision making algorithm is proposed to made the handover decision more appropriate and to avoid loss of communication and provide better performance.
... Along with RSS, the available bandwidth for a station should also be considered in the process of handoff decision. The works [19,[23][24][25] and [26] uses both bandwidth and RSS information for handoff decision. In [27], the estimated life time and available bandwidth are combined with RSS which satisfies the application requirements and user mobility. ...
In the past few years, the deployment of WLAN proliferated throughout the world due to easy installation, low cost and higher bandwidth. The latest IEEE 802.11 standard (802.11n) offers the maximum data rate of about 600 Mbps which makes it an accepted benchmark for deploying WLANs. One of the disadvantages in WLAN is its small coverage which is not suitable for mobiles with high velocity. The alternate network technology for WLAN with almost equal bandwidth and QoS support with wider coverage area is WiMAX, which is one of the rapidly growing technologies across the world. Hence, the integration of WiMAX and WLAN is considered to be a sound approach in 4G. In this paper, we present handoff and integration related issues in WiMAX/WLAN overlay networks, numerical methods for calculating network conditions of both WiMAX and WLAN networks and impact on 802.11n clients by legacy 802.11a/b/g clients. Also, we propose QoS based proactive handoff algorithms for WiMAX/WLAN overlay networks which performs both vertical and horizontal handoffs based on the network condition, acceptable packet delay, required bandwidth and client type. Simulation results demonstrate that the proposed handoff algorithm enhances the QoS significantly.
... RSS based algorithms b) Bandwidth based algorithms: Available bandwidth for a mobile terminal is the main criterion in this group[8][9][10]. In some algorithms, both bandwidth and RSS information are used in the decision process[7]. ...
Nowadays the development of heterogeneous network becomes a paramount necessity; current computing and communication devices are omnipresent and operate in a heterogeneous environment. The users have the privilege to stay connected to the Internet by using mobile terminals equipped with multiple networking interfaces. Thus, the users have the ability to use the services of their choice at anytime and anywhere. These processes of switching between different wireless technologies (Wireless LAN, WiMax, Cellular, UMTS, and LTE etc.) are referred to as Vertical Handovers/Handoffs. The main objective of this contribution is to provide an overview of the state of the art concerning the basics of the handover, its classifications, its desirable characteristics and the analysis of Vertical Handover decision (VHD) algorithms.
... RSS based algorithms b) Bandwidth based algorithms: Available bandwidth for a mobile terminal is the main criterion in this group[8][9][10]. In some algorithms, both bandwidth and RSS information are used in the decision process[7]. ...
Nowadays the development of heterogeneous
network becomes a paramount necessity; current computing and
communication devices are omnipresent and operate in a
heterogeneous environment. The users have the privilege to stay
connected to the Internet by using mobile terminals equipped
with multiple networking interfaces. Thus, the users have the
ability to use the services of their choice at anytime and
anywhere. These processes of switching between different
wireless technologies (Wireless LAN, WiMax, Cellular, UMTS,
and LTE etc.) are referred to as Vertical Handovers/Handoffs.
... The prediction hit rate in all scenarios varies from 47% -20% since it decreases with the increase of neighboring base stations. Finally, Chi et al. [7] suggested two criteria, the wrong decision probability (WDP) and the handover probability (HP), for evaluating handoff schemes and provided mathematical modeling for both measures. ...
Abstract—The recent advances in wireless communications require integration of multiple network technologies in order to satisfy the increasing demand of mobile users. Mobility in such a heterogeneous environment entails that users keep moving between the coverage regions of different networks, which means that a non-trivial vertical handoff scheme is required in order to maintain a seamless transition from one network technology to another. A good vertical handoff scheme must provide the users with the best possible connection while keeping connection dropping probability to the minimum. In this paper, we propose a handoff scheme which employs the Markov model to predict the users’ future locations in order to make better handoff decisions with reduced connection dropping probability and number of unnecessary handoffs. Through simulation, the proposed scheme is compared with the SINR-based scheme, which was shown to outperform other vertical handoff schemes. The experiments show that the proposed scheme achieves significant improvements over the SINR-based scheme that can reach 51% in terms of the number of failed handoffs and 44% in terms of the number of handoffs.
... So probability of handoff computed from RSSs is chosen as criterion for processing handoff from current BS to neighboring BS. The paper [6] gave a mathematical model for Wrong Decision Probability (WDP) and handoff probability (HP) which is used as criteria for the evaluation of handoff algorithm. For better performance WDP predication based handoff algorithm is also proposed as it reduces wrong decisions. ...
... Finally, Chi et al. [17] proposed an analytical model for vertical handoff that uses the distance to the AP as well as Wrong Decision Probability (WDP) and the Handover Probability (HP). This vertical handoff scheme assumes that there are two networks with overlapping coverage areas. ...
In heterogenous wireless networks, as the users move across the coverage regions of possibly-different wireless networks, they will have to switch between them. The procedure followed to determine when and how a mobile user should switch between networks of different types is known as the vertical handoff scheme. Several vertical handoff schemes have been proposed in the literature, but few of them employ the geographical nature of this problem like we do in this paper. The scheme we propose here takes the user's direction of movement into account when choosing the most suitable candidate for the handoff. When compared with existing schemes, our proposed scheme shows significant reductions in the number of lost connections and the number of unnecessary handoffs.
... Finally, Chi et al. [17] proposed an analytical model for vertical handoff that uses the distance to the AP as well as Wrong Decision Probability (WDP) and the Handover Probability (HP). This vertical handoff scheme assumes that there are two networks with overlapping coverage areas. ...
In heterogenous wireless networks, as the users move across the coverage regions of possibly-different wireless networks, they will have to switch between them. The procedure followed to determine when and how a mobile user should switch between networks of different types is known as the vertical handoff scheme. Several vertical handoff schemes have been proposed in the literature, but few of them employ the geographical nature of this problem like we do in this paper. The scheme we propose here takes the user's direction of movement into account when choosing the most suitable candidate for the handoff. When compared with existing schemes, our proposed scheme shows significant reductions in the number of lost connections and the number of unnecessary handoffs.
... When all mobiles enter to the area of multi-access network at the same time a crucial issue to be dealt with is the selection of the suitable network while taking into consideration the decision taken by other mobiles, that is to say, how to select the best network that can fulfill user requirement without creating performance degradation. The selection of network is not done haphazardly; it is done on the basis of certain criteria such as RSS, QoS parameters [1,2] and individual consideration and information [3]. They do not consider the impact introduced by other mobile's decision. ...
The traditional vertical handover schemes postulate that vertical handover of each user comes on an individual basis. This enables the users to know previously the decision already made by other users, and then the choice will be made accordingly. However, in the case of a group vertical handover, almost all the VHO decisions-which will certainly choose the best network, will be made at the same time which will lead to system performance degradation or network congestion. In this paper, we propose a totally decentralized algorithm for network selection which based on the Congestion Game to resolve the problem of network congestion in GVHO. Therefore, the proposed algorithm named Fully Decentralized Nash Learning Algorithm with incomplete information is a prediction done by each mobile in the group that helps them to reach the Nash equilibrium. Simulation results validate the algorithm and show its robustness under two scenarios. In the first one, we examine the algorithm with a fixed number of mobiles in group to evaluate the mixed strategy and the average perceived throughput of mobiles in WIMAX and HSDPA on the basis of iteration. In the second one, we examine the algorithm with different number of mobiles in group for testing the average number of iterations needed to reach the Nash equilibrium. We also compare it with the traditional vertical handover algorithm.
... Now, our mechanism responsible for minimized packet loss is started by the PELER (Step 5). This threshold can be determined by handover decision algorithms that rely on Received Signal Strength (RSS) and other link layer parameters [11]. Once the L2 handover is performed, the MN initiates a L3 handover through the MIPv6 registration process (Step 6). ...
... But it may introduce excessive handoffs with the variation of the SINR. This excessive handoffs is reduced by a VHD heuristic based on the Wrong Decision Probability (WDP) prediction [8]. The WDP is calculated by combining the probability of unnecessary and missing handoffs. ...
Next generation wireless communications will integrate multiple wireless access networks. Vertical handoff plays an important role in heterogeneous networks. In this paper, a prediction based vertical handoff decision algorithm has been proposed based on mobility. A Hidden Markov Model (HMM) predictor has been utilized in this algorithm that can accurately estimate the next location to be visited by a mobile user, given a current and historical movement information. Each Base station (BS) calculates a combined weight value based on current Network Load , Received Signal Strength (RSS) and Power consumption of using the network access device. The home BS then selects an optimum attachment point for the Mobile station (MS) to perform handover, based on the sorted weight values. The effectiveness of the proposed algorithm has been verified by carrying out simulations. The results show that the proposed algorithm achieves 78.5% reduction in packet loss compared to Dynamic Decision Model (DDM). The increase in throughput is about 62.5 % compared to DDM.
... A VHD heuristic [9] based on the Wrong Decision Probability (WDP) prediction. The WDP is calculated by combining the probability of unnecessary handovers and the missing handovers. ...
Next-generation wireless networks are the promising network to provide Always Best connected network. Mobility management is the primary issue in next generation networks. Mobility management comprises of location and handoff management. When mobile user roams in the next generation networks vertical handoff is the main issue. Vertical handoff decision process can be handled by many researchers in the recent years. Vertical handoff process can split in to three phases such as handoff initiation, handoff decision and handoff execution. Initially vertical handoff initiation and decision are taken with respect to the received signal strength (RSS). Many such algorithm experiences the probability of unnecessary handover and handoff failure. In this paper we proposed fuzzy normalized Handoff initiation algorithm (FUN_HoI) module which considers the combination of different input criteria along with RSS to initiate handoff in time to reduce unnecessary handover and handoff failure probability. The special function of FUN_HoI is to take fuzzy normalization of all input criteria after fed in to the Fuzzy inference system (FIS). An importance of fuzzy normalization is to filter unsuitable candidate networks and thus improves the efficiency of an algorithm. The proposed method is compared with the existing algorithm such as RSS based and Bandwidth based algorithm. The comparative study reveals that the proposed method consumes higher delay but reduced handover probability and unnecessary handoff.
... The effectiveness of their technique has been evaluated in terms of number of vertical handovers only, and no network parameter has been investigated. In [14] Chi et al. propose a technique for limitation of the ping-pong effect, by exploiting the estimation of the Wrong Decision Probability, i.e. the probability that an unnecessary handover is initiated, and then executed. A similar concept has been assumed in [45], where the Wrong Decision Probability calculus is based on a linear correlation between goodput performances measured at different time samples. ...
... Another important issue of next-generation wireless network design is the integration of heterogeneous wireless networks, including wireless local area networks (WLANs) and cellular networks such as 3GPP-LTE and WiMAX. In dealing with heterogeneous wireless networks, there are two different approaches, namely network selection and multi-homing: Network selection chooses the most appropriate access network among all available alternatives [3], [4], whereas multi-homing simultaneously accesses to multiple wireless network interfaces [5]. Multi-homing has advantages in mobility support, load balancing, and high data rate provision. ...
In this paper, we present a resource allocation algorithm for energy consumption minimization in multi-homed wireless networks, simultaneously connecting to different wireless interfaces. Specifically, we first formulate a general problem related to minimization of energy consumption while satisfying minimum rate requirements. Then, we solve the problem by relaxing integer value constraints and applying Lagrangian Lagrangian dualityduality. For a given set of dual variables, we derive optimal resource allocation policies by using an efficient dual update method. Numerical results reveal that the optimal allocation algorithm outperforms the existing resource allocation algorithms for homogeneous networks in terms of the energy consumption reduction as well as energy efficiency of the overall network.
... While some authors only use RSS as an input parameter for the handoff decision process [10,21], others combine the use of RSS with bandwidth information [22][23][24]. Using cost functions has been proposed earlier [14][15][16]. ...
The increasing demand for real-time multimedia streaming from mobile users makes important deployment of network selection in wireless networks. Coexistence of various wireless access networks and ability of mobile terminals to switch between them make an optimal selection of serving mobile
networks for groups of mobile clients a challenging problem. Since scalability can easily become a bottleneck in large-scale networks, we study the decision-making process and selection of the data that needs to be exchanged between different network components. In this paper, we present two decentralized solutions to this problem that we compare and evaluate in the OMNet++ simulation environment.
... Thus, [7] shows a comprehensive survey of the VH decision algorithms designed to provide the required QoS to a wide range of applications. These algorithms are categorized into four groups based on the decision criteria used (received signal strength [8][9][10], bandwidth [11][12][13], cost function [14][15][16], or combination [17][18][19]). Also, [20] exposes an overview of VH decision algorithms, grouping them as traditional, functionbased, user-centric, multiple attributes decision making, fuzzy logic and neural networks, and context-aware algorithms. ...
One of the most important aspects of the modern communications deals with the access to wireless networks by mobile devices, looking for a good quality of service under the user’s preferences. Nevertheless, a mobile terminal can discover more than one network of different technology along its trajectory in heterogeneous scenarios, being capable of connecting to other wireless access points according to their quality of service values. This is the case of the vertical handoff decision phase, present in many sceneries such as 3G-LTE access networks. In this context, an efficient resource management of the different networks (a good selection of weights for their quality of service parameters) constitutes an optimization problem, where several heuristic methods using simple rules try to find the best available network. Nevertheless, the characteristics of the current mobile devices advise to use fast and efficient algorithms to provide solutions near to real-time. These constraints have moved us to develop intelligent algorithms that avoid the slow and massive computations associated with direct search techniques, so reducing the computation time. In this paper we propose an evolutionary algorithm capable of computing rapidly in embedded processors, improving the performance of other algorithms designed in order to solve this optimization problem.
One of the biggest challenges in wireless networks of new generation (NGWS : Next Generation Wireless Network) is the vertical handover (VHO) during the user's mobility between the different types of technologies (3GPP and non-3GPP) such as e.g 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). As a result, telecoms operators must develop an interoperability strategy for these different types of existing networks in order to get the best connection anywhere and anytime, without disrupting ongoing sessions. We propose a new optimized VHO approach based on VHO approaches studied in the literature and considering the research issues and insight that emerged in our investigations. The proposed approach shows better performance (packet loss, latency and ensuring the continuity of the communication session during handover) compared to what is found in the literature. It consists of a procedure consisting of three-phase: (Handover Initiation, handover decision and handover execution) and a decision algorithm to select the best network among those available in the handover decision phase. The proposed method is based on IEEE 802.21(MIH), a loose coupling architecture and Mobile Internet Protocol Version 4 (MIPv4) which provides an early buffer for new data packets to minimize packet loss and VHO latency. The proposed decision algorithm consists of two VHO selection functions (ANSFi, ANSFa) and a priority list of different radio access technologies (RAT). We consider two main types of VHO: imperative VHO case due to the power of the radio signal (RSS) power drops, in this case applied ANSFi selection function or alternative VHO case based on user preferences (e.g., high data throughput, low cost) applied the ANSFa election function to give a list of priority RAT based on ANSFi or ANSFa to minimize VHO connection failure and gives priority to mandatory sessions plus alternate sessions. The analysis results of the simulation show that our proposed approach outperforms other conventional approaches in terms of reducing vertical handover latency reduction and packet loss, ensuring continuity of the communication session during the handover.
Ensuring reliable and stable communication during the movements of mobile users is one of the key issues in mobile networks. In the recent years, several studies have been conducted to address the issues related to Handover (HO) self-optimization in Heterogeneous Networks (HetNets) for Fourth Generation (4G) and Fifth Generation (5G) mobile networks. Various solutions have been developed to determine or estimating the optimum and ideal settings of Handover Control Parameters (HCPs), such as Time-To-Trigger (TTT) and Handover Margin (HOM). However, the complexity, high requirements, and the upcoming structure of ultra-dense HetNets require more advanced HO self-optimization techniques for future implementation. This paper studies HO self-optimization techniques that may implemented in the next-generation mobile HetNets by reviewing state-of-the-art algorithms. The solutions discussed in this survey are more focus on Mobility Robustness Optimization (MRO), which is a significant self-optimization function in 4G and 5G mobile networks. The applied solutions will preserve the continuous connection between the User Equipment (UE) and eNBs during UE mobility, thereby enhancing connection quality. The various algorithms and techniques applied to HO have revealed different outcomes. This paper discusses the pros and cons of these techniques, and further examines HO self-optimization challenges and solutions. New future directions for the implementation of HO self-optimization are also identified. This survey will contribute to the understanding of the issues related to mobility management, particularly in relation to the self-optimization of HO control parameters in future mobile HetNets.
Heterogeneous networks are designed to offload or route some of data traffics of mobile networks through other co-located wireless access networks. This technique apparently increases the capacity of mobile network. In such networks, a vertical handover process plays an important role in providing seamless and uninterrupted connectivity as well as the required level of quality-of-service along with a wide coverage for all mobile nodes. Traditional vertical handover algorithms that are based on single criterion (eg, received signal strength) are not performing well in terms of excess handover rates, ping-pong effects, handover delays, handover cost, etc. This research presents an efficient multicriteria-based vertical handover decision-making algorithm for heterogeneous networks. This algorithm uses a two-step execution procedure, the first step evaluates whether the handover is needed or not before initiating a handover process, if needed, then a set of feasible solutions are generated for the vertical handover problem formulated as a multi-objective optimization problem with two objective functions such as quality factor of networks and handover processing cost. In the second step, an optimal solution (ie, an appropriate access network) for handover is obtained using a hybrid approach of fuzzy analytic hierarchy process (FAHP) and technique for order preference by similarity to ideal solution (TOPSIS). Our simulation study shows that the proposed algorithm performs well as compared to some other existing algorithms (ie, single-criterion based, multicriteria with AHP, multicriteria with TOPSIS, and multicriteria with both AHP and TOPSIS) in terms of performance metrics such as handover rate, delay, cost, and energy consumption.
Because of the low throughput and the high packet error rate in wireless communications, the network traffic often converges at access points (APs), which take a role of connecting wired and wireless communication interfaces, and APs are usually bottleneck points in wireless networks. In heterogeneous networks, various networks are around mobile devices. Furthermore, today's mobile devices have various wireless network capabilities. Thus, mobile devices should be able to understand network situations autonomously and use a wide range of network options in heterogeneous networks. However, since current mobile devices cannot know the connected AP's network condition, they continue to use the AP, which provides poor-quality networks even though there are other available APs and networks nearby. To resolve the aforementioned problems, we propose MAPS, the low-power AP monitoring scheme for handover decision triggering in heterogeneous networks. Using MAPS, a mobile device can trigger a handover decision properly through predicting the connected AP's network condition accurately without any cooperation from other devices. Furthermore, MAPS does not require any modification on existing network systems, and the mobile device can use MAPS with simple application installation. Through diverse simulations, actual experiments, and power consumption analysis, we validate that MAPS can detect the busy AP effectively and is suitable for mobile devices because of low power consumption.
Heterogeneous networks allow mobile nodes to take advantage of best radio facilities for their coexisting connections. Vertical handover (VHO) between them is required to perform Always Best Connected (ABC). VHO is one of the most challenging research issues for wireless networks. The traditional decision making schemes cannot meet the VHO requirements of mobile networks, and the performance may degrade severely due to the unique characteristics of mobile networking. Therefore, optimized handover management schemes, developed specifically for heterogeneous wireless networks are required. In order achieve an optimum VHO decision, this paper propose a solution to the tough VHO decision problem through a novel approach based on multiple classifiers application. Our aim is to survey recent development of this field and to present the prospective of utilizing statistical classifiers to handle the challenging VHO requirement. The architecture design of the proposed approach is presented. Various components that constitute the road map toward development of the multi-classifier based VHO scheme are discussed.
There are some corrections to the text on the following pages:
1. In page 371, instead of LMP, it should be AS:
When MH moves out of the service area of the current AS, L2 and/or L3 handover should be executed initially.
2. In page 373, instead of MMH, it should be MH.
Inter-Subnet Handover - When a MH moves from one subnet to another, within the same GW, an IP handover takes place. This is known as L3 Handover. IPv6 protocol stack in MH is notified by a local event that triggers IP handover.
3. In page 376 and 377, the unit of velocity is ‘m/s’ instead of ‘ms’.
Velocity of the mobile node is varied from 2 m/s to 40 m/s and the packet loss rate is observed during L2 and L3 handover.
Velocity of the mobile node is varied from 2 m/s to 40 m/s and the handover latency is observed during layer 2 and layer 3 handover.
Mobility management enables the Mobile Terminal to switch between networks for better resource management and is still a hot research topic. Handoff management is one such challenge for maintaining active connections for roaming mobile terminals, as they change their network point of attachment. In heterogeneous networks, it is critical to evaluate and select the best algorithm out of the different algorithms, available for vertical handoff. Wrong decision probability (WDP) is one of the performances metric which is used to measure the efficiency of handover algorithms in providing such seamless service. In this work, probability equations are derived for five network models and probabilities are computed for unnecessary handover, missing handover and wrong decisions. The handoff algorithm for the five network model is designed to evaluate the performance of algorithms designed based on combination of received signal strength and bandwidth using Wrong Decision Probability model. Presentation of analytical and simulation results is made to validate the vertical handover and is compared with the results of handoff algorithm for the five network model designed considering bandwidth alone.
With the rapid development of wireless sensor techniques and wireless communication techniques in recent years, Wireless Sensor Networks (WSN) has achieved significant improvements. Sensor nodes deployment can be static or dynamic. The support of the mobility becomes one of the important issues in WSN. The problem caused by frequent topology changes is to find a tradeoff between reliability and energy efficiency. Inspired by wireless networks Radio Resource Management (RRM), we introduce handover management strategies to solve the problem. In this research, we therefore deliver some novel WSN based handover techniques under various conditions. (5 pages)
A self-organizing network (SON) is effectively realized by means of specific SON mechanisms , which relate to particular SON use cases , these being defined by the Third-Generation Partnership Project (3GPP) and Next Generation Mobile Networks (NGMN). Typically, are grouped into self-configuration, self-optimization, and self-healing functions. Focusing on self-optimization, therein aim at maintaining relevant key performance indicators (KPIs) above/below a specific target by actuating over an appropriate set of input parameters to achieve predefined network objectives. Typically, this problem is represented by several control loops where controllable input parameters are dynamically adjusted according to output measurable metrics and their corresponding target requirements. From an implementation viewpoint, the concept of a single SON “black box,” integrating multiple , is very appealing. However, this approach may threaten the control that network operators (NOPs) have over their own network. As a result, a coordinated framework involving stand-alone is proposed. Here, a SON controller may be implemented responding to strategies, deciding at a given time which actions have higher priority with respect to others. In the context of a heterogeneous network (Het- et) scenario, we propose and develop a simplified framework where stand-alone react to either overshot or undershot KPI events by deciding to either increase or decrease corresponding influential parameter(s). By inspecting the arising interactions and possible conflicts between several , we provide, for a specific evaluation scenario, a heuristic strategy-based solution for SON coordination, which may eventually trade off high-level NOP goals.
We propose a new framework, based on signal quality, for performance evaluation and comparison between existing handoff algorithms. It includes new call quality measures and an off-line cluster-based computationally-simple heuristic algorithm to find a near optimal handoff sequence used as a benchmark. We then compare existing handoff algorithms and identify the trade-off between signal quality and number of handoffs.
For the same long-term loss ratio, different loss patterns lead to different application-level Quality of Service (QoS) perceived by the users (short-term QoS). While basic packet loss measures like the mean loss rate are widely used in the literature, much less work has been devoted to capturing a more detailed characterization of the loss process. In this paper, we provide means for a comprehensive characterization of loss processes by employing a model that captures loss burstiness and distances between loss bursts. Model parameters can be approximated based on run-lengths of received/lost packets. We show how the model serves as a framework in which packet loss metrics existing in the literature can be described as model parameters and thus integrated into the loss process characterization. Variations of the model with diferent complexity are introduced, including the well-known Gilbert model as a special case. Finally we show how our loss characterization can be used by applying it to actual Internet loss traces.
Abstract The convergence of heterogeneous wireless access technologies has been envisioned to characterize the next generation wireless networks. In such converged systems, the seamless and efficient handoff between different access technologies (vertical handoff) is essential and remains a challenging problem. The heterogeneous,co-existence of access technologies with largely different characteristics results in handoff asymmetry,that differs from the traditional intra-network handoff (horizontal handoff) problem. In the case where one network is preferred, the vertical handoff decision should be carefully executed, based on the wireless channel state, network layer
Roaming across heterogeneous wireless networks such as wireless wide area network (WWAN) and wireless local area network (WLAN) poses considerable challenges, as it is usually difficult to maintain the existing connections and guarantee the necessary quality-of-service. This paper proposes a novel seamless and proactive end-to-end mobility management system, which can maintain the connections based on the end-to-end principle by incorporating an intelligent network status detection mechanism. The proposed system consists of two components, connection manager (CM) and virtual connectivity (VC). The CM, by using novel media access control-layer and physical-layer sensing techniques, can obtain accurate network condition, while at the same time reducing the unnecessary handoff and ping-pong effect. The VC can make mobility transparent to applications without additional network-layer infrastructure support using a local connection translation, and can handle mobility well in the network address translator and simultaneous movement cases using a subscription/notification service. The proposed system enjoys several unique advantages: 1) capable of reacting to roaming events proactively and accurately; 2) maintaining the connection's continuity with small handoff delay; and 3) being a unified end-to-end approach for both IPv4 and IPv6 networks. We have built a prototype system and performed experiments to demonstrate the advantages of the proposed system.
This paper evaluates the internetwork handover performance in a
GSM and satellite integrated mobile communication system. The
performance evaluation is based on an analytical model developed for
internetwork handover. The handover performance parameters considered
are the handover position, unnecessary handover probability, and
call-dropping probability. Handover initiation is based on the signal
level and distance measurement. The results are compared with those of
the GSM handover performance. The analysis shows that the performance
achieved in internetwork handover can be similar to those of the GSM
handover with the considered handover initiation scheme