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Top1. Introduction
Reducing the interruption in handover is the main handover prediction advantages. Redundant handovers numbers (unnecessary handovers) can be reduced when designing an expert and a proper handover prediction. While mobile stations (MS’s) moving nearby the edge of cell borders, it may switch between two adjacent stations continuously, this is called the ping-pong impact which is the fundamental reason behind redundant handover (Becvar & Mach, 2013). Delay in handover is a vital problem in wireless and mobile networks connections. Considerable attempts have been made by researchers to design an appropriate solution to reduce handover delays. Hysteresis Margin (HM) (Yusof et al., 2013) and Time-To-Trigger (TTT) (Khan & Han, 2014) are examples of techniques which can be used for limiting the redundant handovers (Bao et al., 2011; Luo 2013).
Handover process is divided into two types; horizontal and vertical handover. Handover is termed as horizontal when the MS moved between two stations with the same network form. Otherwise, the handover is called vertical as illustrated in Figure 1. The process of managing the vertical handover in an efficient and a perfect way is considered a strong challenge. Therefore, current handover procedures need to be enhanced to avoid the non-noticeable conflicts, to ensure a stable connection when the MS moves between different networks, and to reduce the number of redundant handovers (Grech, 2017).
There are differences between WLANs and mobile networks, in terms of several protocols stacks, mobility tools, network access structures, QoS and so on. Hence, conventional interconnecting between these types of networks is not straight forward, even though both are IP-based structures. I-WLAN (3GPP 2017) is considered the primary strategy described basically for the integration of WLAN networks. It is proposed with 3GPP mobile structure. This structure describes the misunderstanding between both networks with data, access protocols, control behaviors and authentication procedure.
Therefore, designing a prediction scheme is a vital task, which is utilized to predict the desired handover station before handover occurs. Executing the handover procedure more smoothly and efficiently and guarantying the continuous connectivity through handover are considered the most benefit of handover prediction scheme (Hosny et al., 2019). There are many handover decision methodologies which have been proposed lately for both horizontal and vertical handover for different mobile networks, for example: Long Term Evolution (LTE) (Han & Wu, 2010) and 3G (Javed et al., 2011) as examples of horizontal handover. Handover between 3rd Generation Partnership Project 3GPP and Wireless Local Area Networks (WLANs) (Qamar et al., 2017), LTE and the Worldwide Interoperability for Microwave Access (WiMAX) (Miyim et al., 2012) are examples of vertical handover.