Handover in Mobile Wireless Communication Network - A Review <s> III. <s> The next generation in mobility management will enable different mobile networks to interoperate with each other to ensure terminal and personal mobility and global portability of network services. However, in order to ensure global mobility, the deployment and integration of both satellite and terrestrial components are necessary. This article is focused on issues related to mobility management in a future mobile communications system, in a scenario where a multisegment access network is integrated into an IP core network by exploiting the principles of Mobile IP. In particular, attention is given to the requirements for location, address, and handover management. In a heterogeneous environment, the need to perform handover between access networks imposes particular constraints on the type of information available to the terminal and network. In this case, consideration will need to be given to parameters other than radio characteristics, such as achievable quality of service and user preference. This article proposes a new approach to handover management by applying the fuzzy logic concept to a heterogeneous environment. The article concludes with a presentation of mobility management signaling protocols. <s> BIB001 </s> Handover in Mobile Wireless Communication Network - A Review <s> III. <s> In the next generation heterogeneous wireless networks, a user with a multi-interface terminal may have a network access from different service providers using various technologies. It is believed that handover decision is based on multiple criteria as well as user preference. Various approaches have been proposed to solve the handover decision problem, but the choice of decision method appears to be arbitrary and some of the methods even give disputable results. In this paper, a new handover criteria is introduced along with a new handover decision strategy. In addition, handover decision is identified us a fuzzy multiple attribute decision making (MADM) problem, and fuzzy logic is applied to deal with the imprecise information of some criteria and user preference. After a systematic analysis of various fuzzy MADM methods, a feasible approach is presented. In the end, examples are provided illustrating the proposed methods and the sensitivity of the methods is also analysed. <s> BIB002 </s> Handover in Mobile Wireless Communication Network - A Review <s> III. <s> This paper addresses a movement-aware vertical (MAV) handover algorithm between WLAN and Mobile WiMAX for seamless ubiquitous access. An MAV handover algorithm is proposed in this paper to exploit movement pattern for avoiding unnecessary handovers in the integrated WLAN and Mobile WiMAX networks. If a mobile station (MS)'s velocity is high and its movement pattern is irregular, unnecessary handovers likely occur more frequently. Therefore, the MS velocity and moving pattern are important factors for the handover decision procedure. To avoid unnecessary handovers, the MAV handover algorithm adjusts the dwell time adaptively and predicts the residual time in the cell of target base station (BS). Consequently, the adaptive dwell timer of MAV handover algorithm allows an MS a better connection as long as possible. Our simulation results show that the reduction of unnecessary handovers by leads to significant throughput improvements. <s> BIB003 </s> Handover in Mobile Wireless Communication Network - A Review <s> III. <s> One of the major design issues in heterogeneous wireless networks is the support of vertical handoff. Vertical handoff occurs when a mobile terminal switches from one network to another (e.g., from WLAN to CDMA 1timesRTT). The objective of this paper is to determine the conditions under which vertical handoff should be performed. The problem is formulated as a Markov decision process. A link reward function and a signaling cost function are introduced to capture the tradeoff between the network resources utilized by the connection and the signaling and processing load incurred on the network. A stationary deterministic policy is obtained when the connection termination time is geometrically distributed. Numerical results show good performance of our proposed scheme over two other vertical handoff decision algorithms, namely: SAW (simple additive weighting) and GRA (grey relational analysis). <s> BIB004 </s> Handover in Mobile Wireless Communication Network - A Review <s> III. <s> In this paper we introduce and examine via simulations, a Markov decision process (MDP) based approach for vertical handover decision-making. We consider here the case of a heterogeneous network environment where both the legacy WLAN and the novel line-of-sight (LOS)- dependent 60 GHz radio systems are deployed to support indoor high quality multi-media applications. The MDP decision approach takes into account multiple factors such as user preference, network situation, device capability and effects of environment. We show its ability to effectively make handover decision in uncertain situations. The method and results herein are applicable, in general, to any other situation where such a decision is to be made. <s> BIB005 </s> Handover in Mobile Wireless Communication Network - A Review <s> III. <s> There are currently a large variety of wireless access networks, including the emerging vehicular ad hoc networks (VANETs). A large variety of applications utilizing these networks will demand features such as real-time, high-availability, and even instantaneous high-bandwidth in some cases. Therefore, it is imperative for network service providers to make the best possible use of the combined resources of available heterogeneous networks (wireless area networks (WLANs), Universal Mobile Telecommunications Systems, VANETs, Worldwide Interoperability for Microwave Access (WiMAX), etc.) for connection support. When connections need to migrate between heterogeneous networks for performance and high-availability reasons, seamless vertical handoff (VHO) is a necessary first step. In the near future, vehicular and other mobile applications will be expected to have seamless VHO between heterogeneous access networks. With regard to VHO performance, there is a critical need to develop algorithms for connection management and optimal resource allocation for seamless mobility. In this paper, we develop a VHO decision algorithm that enables a wireless access network to not only balance the overall load among all attachment points (e.g., base stations and access points) but also maximize the collective battery lifetime of mobile nodes (MNs). In addition, when ad hoc mode is applied to 3/4G wireless data networks, VANETs, and IEEE 802.11 WLANs for a more seamless integration of heterogeneous wireless networks, we devise a route-selection algorithm for forwarding data packets to the most appropriate attachment point to maximize collective battery lifetime and maintain load balancing. Results based on a detailed performance evaluation study are also presented here to demonstrate the efficacy of the proposed algorithms. <s> BIB006 </s> Handover in Mobile Wireless Communication Network - A Review <s> III. <s> Designing of heterogeneous wireless environment involves several internetworking issues, such as seamless handoff or roaming, mobility management, security and accounting problem etc. One of the major issues in next- generation heterogeneous networks is the issue of vertical handoff for guaranteeing service continuity and quality of service. This paper reports on the design and implementation of multi-criteria vertical handoff decision algorithms in heterogeneous wireless environment. A neural network model has been used to process multi-criteria vertical handoff decision metrics. <s> BIB007 </s> Handover in Mobile Wireless Communication Network - A Review <s> III. <s> To attain a flawless real-time data transfer over a communication channel of Industrial Wireless Sensor Networks (IWSNs) is a difficult issue. The reason is that data transmission reliability degrades remarkably due to the dynamically changing network topology. Although TDMA-based protocols are widely used for real-time data transmission in IWSNs, they are not suitable for dynamically changing network topology. Therefore, we analyze the communication behavior of real-time multimedia data transmission and try to find out some performance enhancing factors. Then, we propose a slotted-sense scheduling scheme in which a big time slot is shared among the nodes at same tree-level. A sharable slot not only assures the time constraint but also improves the reliability of multimedia data greatly. Moreover, the block data transmission technique with an adaptive acknowledgement is proposed to optimize the size of a sharable slot. Finally, the experimental results show that our approach outperforms other standard MAC protocols for real-time multimedia data transmission in IWSNs. <s> BIB008
REVIEW OF SOME LITERATURE In  , a fuzzy rule based algorithm which is QoS aware that uses bandwidth, E2E delay, jitter and BER as fuzzy inference system (FIS) inputs for handover decision making was proposed. The algorithm was simulated using Conversational, Streaming, Background traffic classes and Interactive. The algorithm gives better QoS performance where delay is less desirable. In BIB006 , a vertical handover decision algorithm was proposed. It maximizes the overall MS battery lifetime and the algorithm also aim at traffic load balancing across the networks. This algorithm, according to BIB008 , VHD function can be provided for a region covering one or more AP/BS when implemented in a multiple VHD Controller (VHDC) available in the networks. In  , proposed a Received Signal Strength (RSS) based algorithm called ALIVE-HO (adaptive lifetime-based vertical handover) for decision making. With this algorithm, RSS was used to estimate wireless network coverage and selects the best network in it. The algorithm also employed MT velocity to reduce unnecessary handovers, and the effect of Ping-Pong but the HO Probability is directly proportional to distance from the access point. The algorithm proved better than traditional handover algorithm on the scale of the number of handovers. For vertical handover decision, QoS parameters and handover metrics are needed to be considered  . In  , proposed a handover decision mechanism by formulating an optimization problem. A cost function was assigned to each candidate network. The choice depends on the lowest cost value. The criteria of cost function are handover delay, available bandwidth and power requirement. Each criterion is assigned with appropriate weight factor based on its important. In  proposed a utility based algorithm called Active Application Oriented (AOO) vertical handover decision mechanism. The quality of service parameters required for the applications is considered in the algorithm. Utility function is assigned to every associated candidate network and the highest utility value network is selected. The weighted sum of various normalized QoS parameters is called utilization function.  proposed an algorithm which detects decay in signal using neural networks-based approach to make HO decision. In BIB001 , Chan et al. proposed a multi-segment mobility management, which is based on packet through the concept of fuzzy logic and Mobile IP. W. Zhang in BIB002 proposes a VHD decision which is formulated using "fuzzy-based multiple attribute decisionmaking (MADM) problem". Fuzzy logic is employed to handle the imprecision in the formation of some attributes of the networks and the user's preferences. In BIB005 , a "Markov decision process (MDP)" is proposed for VHO decision making. The approach considered many parameters like network conditions, user preference and device capability. A lot of VHD algorithms have been developed and many of which employed Fuzzy logic theory which has shown greater advantage over traditional (single parameter based) algorithm which has no database to store rule bases. Mali 2017  proposed a Fuzzy Based VHD Controller for Future Networks targeted on network selection during handover processes. The author considered more than fifteen (15) parameters and divided the handover process into six systems (A -F). System A provides available networks report at mobile device periodically and their respective QoS parameters. System B at the base station receives these parameters and feed it to the next stage. System C retrieve the data from the stack if system B and feed system D to set the fuzzy rules. E is called knowledge base module and the decision is taking by F. The method solved the problem of latency and reduces the call drop rate. Meanwhile, there is need to integrate more and more parameter into the controller for more accuracy. In  ,DebabrataSarddar et al proposed a GPS based handover technique for handover probability enhancement in NGWS (Next Generation Wireless System). The authors used GPS to determine the direction of the velocity of the MT (Mobile Terminal) and thereby ensured efficient handoff. The efficiency of this work is dependent on if at different time interval the angles are stored in memory and compared for a specific time interval means for perfectness we required huge data with huge memory capacity. In BIB003 ,Wonjun Lee et al proposed a handover algorithm based on mobile user movement MAV (Movement Aware Vertical handover). It uses patterns of movement to avoid handovers between WLAN and Mobile WiMAX networks when it is not necessary. In the MAV, the dwell time adaptively changes and the targeted base station (BS) predicts the residual time. MAV provides better connection to MS as long as possible. The work is effective to handover Ping-Pong effect through dwell time, but it required to cover the detection technique of actual cell boundary also consider coverage based mechanism for efficient handover. In  , Dong Ma et al also proposed a QoS-based VHO algorithm for WLAN and WiMAX which uses bandwidth estimation algorithm. This scheme evaluates the overlay networks real-time status to makes a handover decision. The deficiency of the proposed algorithm was that handover process will be initiated by unaccepted signal strength which will produce unsatisfied QoS parameters. For effective QoS handover, there is need for latest parameter in order to maintain QoS like network cost, load balancing and so on. In  ,P.Vetrivelan and P.Narayanasamy, a "seamless media independent resilience triggering (SMIRT) framework" for HetNets (Wi-Fi, WI-MAX and LTE) is proposed which employed soft-handover mechanism. A seamless roaming is provided through the MIR-HO framework with user's exclusion in a HetNet by the proposed method. One of the key factors of resource utilisation efficiency is call admission control (CAC). This is being performed during either new call or handover communication. In this, when the BW (bandwidth) is not sufficient for call admission, the bandwidth will be adaptively allocated to accommodate the call. But, there is need for effective and unique algorithm which will cover every issue and take an effective decision within a short time also unnecessary handover situation is not considered. In  , Wang et al proposed policy-enabled handover algorithm. The users set some rules which determine the best network based on the network parameters (dynamic and statics) thereby present the cost function. This algorithm is not capable to handle sophisticated configuration. In BIB004 ,E.Stevens,Wong proposed VHD algorithm for heterogeneous network by using duration of connection and load signaling to perform vertical handover. The algorithm uses MDP to maximize total reward of connection expected. The algorithm reduces the number of VHO expected when compared with methods like simple additive weighting (SAW) method and GRA (grey relational analysis). In  ,Dvir et al HO algorithm for HetNet is proposed. A decision function is based on host velocity, battery status, current load on the network and so on as related to the available network. The new systemwise-entity is defined when UE moved to the overlapping region. Then,, the technology selection is carried out by the entity to optimize the system performance. In this we required to cover the parameters which detect the false situation also along with all latest parameter. In BIB007 ,Chandralekha et al proposed a best wireless network selection theory which is based on the preferences set by the UE. The network with a reasonable performance rate is selected. The selection must be done carefully because it is the selected network performance rate is used as input to NN so that the performance rate might be high. In  , Goyal et al proposed a VHO model which is dynamic across HetNet. The algorithm selects the best network using RSS, velocity of a mobile node and statics factors. The algorithm has three phases which are: the priority (used for the removal of ineligible network), normal (used for accommodating user predefined preference) and decision (used to select the best network). The network interface and base station parameters are monitored by HMC (handover Management Centre), analyze it and make HO decisions.