81 research outputs found

    IP-Based Mobility Management and Handover Latency Measurement in heterogeneous environments

    Get PDF
    One serious concern in the ubiquitous networks is the seamless vertical handover management between different wireless technologies. To meet this challenge, many standardization organizations proposed different protocols at different layers of the protocol stack. The Internet Engineering Task Force (IETF) has different groups working on mobility at IP level in order to enhance mobile IPv4 and mobile IPv6 with different variants: HMIPv6 (Hierarchical Mobile IPv6), FMIPv6 (Fast Mobile IPv6) and PMIPv6 (Proxy Mobile IPv6) for seamless handover. Moreover, the IEEE 802.21 standard provides another framework for seamless handover. The 3GPP standard provides the Access Network and Selection Function (ANDSF) to support seamless handover between 3GPP – non 3GPP networks like Wi-Fi, considered as untrusted, and WIMAX considered as trusted networks. In this paper, we present an in-depth analysis of seamless vertical handover protocols and a handover latency comparison of the main mobility management approaches in the literature. The comparison shows the advantages and drawbacks of every mechanism in order to facilitate the adoption of the convenient one for vertical handover within Next Generation Network (NGN) environments. Keywords: Seamless vertical handover, mobility management protocols, IEEE 802.21 MIH, handover latenc

    Motorized cart

    Get PDF
    Motorized cart is known as an effective tool and timeless that help people carry heavy loads. For farmers, it has an especially vital tool for moving goods. Oil palm farmers typically uses the wheelbarrow to move the oil palm fruit (Figure 10.1). However, there is a lack of equipment that should be further enhanced in capabilities. Motorized carts that seek to add automation to wheelbarrow as it is to help people save manpower while using it. At present, oil palm plantation industry is among the largest in Malaysia. However, in an effort to increase the prestige of the industry to a higher level there are challenges to be faced. Shortage of workers willing to work the farm for harvesting oil palm has given pain to manage oil palm plantations. Many have complained about the difficulty of hiring foreign workers and a high cost. Although there are tools that can be used to collect or transfer the proceeds of oil palm fruits such as carts available. However, these tools still have the disadvantage that requires high manpower to operate. Moreover, it is not suitable for all land surfaces and limited cargo space. Workload and manpower dependence has an impact on farmers' income

    Handover management in mobile WiMAX using adaptive cross-layer technique

    Get PDF
    The protocol type and the base station (BS) technology are the main communication media between the Vehicle to Infrastructure (V2I) communication in vehicular networks. During high speed vehicle movement, the best communication would be with a seamless handover (HO) delay in terms of lower packet loss and throughput. Many studies have focused on how to reduce the HO delay during lower speeds of the vehicle with data link (L2) and network (L3) layers protocol. However, this research studied the Transport Layer (L4) protocol mobile Stream Control Transmission Protocol (mSCTP) used as an optimal protocol in collaboration with the Location Manager (LM) and Domain Name Server (DNS). In addition, the BS technology that performs smooth HO employing an adaptive algorithm in L2 to perform the HO according to current vehicle speed was also included in the research. The methods derived from the combination of L4 and the BS technology methods produced an Adaptive Cross-Layer (ACL) design which is a mobility oriented handover management scheme that adapts the HO procedure among the protocol layers. The optimization has a better performance during HO as it is reduces scanning delay and diversity level as well as support transparent mobility among layers in terms of low packet loss and higher throughput. All of these metrics are capable of offering maximum flexibility and efficiency while allowing applications to refine the behaviour of the HO procedure. Besides that, evaluations were performed in various scenarios including different vehicle speeds and background traffic. The performance evaluation of the proposed ACL had approximately 30% improvement making it better than the other handover solutions

    Interworking Architectures in Heterogeneous Wireless Networks: An Algorithmic Overview

    Get PDF
    The scarce availability of spectrum and the proliferation of smartphones, social networking applications, online gaming etc., mobile network operators (MNOs) are faced with an exponential growth in packet switched data requirements on their networks. Haven invested in legacy systems (such as HSPA, WCDMA, WiMAX, Cdma2000, LTE, etc.) that have hitherto withstood the current and imminent data usage demand, future and projected usage surpass the capabilities of the evolution of these individual technologies. Hence, a more critical, cost-effective and flexible approach to provide ubiquitous coverage for the user using available spectrum is of high demand. Heterogeneous Networks make use of these legacy systems by allowing users to connect to the best network available and most importantly seamlessly handover active sessions amidst them. This paper presents a survey of interworking architectures between IMT 2000 candidate networks that employ the use of IEFT protocols such as MIP, mSCTP, HIP, MOBIKE, IKEV2 and SIP etc. to bring about this much needed capacity

    The seamless vertical handover between (universal mobile telecommunications system) UMTS and (wireless local area network) WLAN by using hybrid scheme of Bi-mSCTP in mobile IP

    Get PDF
    Nowadays many different types of networks communicate among themselves to form heterogeneous wireless networks (HWN). Seamless vertical handover (VHO) between a Universal Mobile Telecommunications System (UMTS) and a Wireless Local Area Network (WLAN) is necessary to provide continuous internet access for mobile node (MN) as roaming across these networks is to be without interruption. To support the seamless VHO and smooth mobility in the HWN, a network layer protocol mobile IP (MIP) is exploited. MIP has several attendant issues such as hybrid routing, registration delay, data session disruption during VHO, and packet overhead. These issues occur when the data packets of the MIP are sent from a foreign agent (FA) to a home agent (HA) via a tunnel when a MN moves to a new network which will cause a triangle routing. In this paper, we propose a hybrid scheme of mobile stream control transmission protocol (mSCTP) with a bicasting mechanism or so- called Bi-mSCTP under the MIP to overcome the abovementioned triangle routing. When an MN is in the area of VHO, the proposed scheme relies on the generated mSCTP signals to allocate a new care-of- address (CoA) to the corresponding node (CN) dynamically before the link layer handover. At the same time, it inserts a bicasting flag inside the address configuration (ASCONF) data chunk to inform the CN to start the transmission over both WLAN and UMTS links. The system performances were analyzed by using the NS-2 simulation tool. The results showed that the hybrid scheme introduces approximately 1.02 and 2.64 seconds reduction in delay performance over both mSCTP and MIP schemes respectively. It also reduces the packet loss rate by more than 21.7 and 45% compared to mSCTP and MIP respectively

    Intégration et gestion de mobilité de bout en bout dans les réseaux mobiles de prochaine génération

    Get PDF
    Résumé - Pendant les dix dernières années, l'utilisation des systèmes de communication sans fil est devenue de plus en plus populaire tant chez les entreprises que chez les particuliers. Cette nouvelle tendance du marché est due, en grande partie, à la performance grandissante des réseaux mobiles qui concurrencent davantage les réseaux filaires en termes de bande passante, de coût et de couverture. Toutefois, cette catégorie de solutions sans fil est conçue pour des services spécifiques et utilise des technologies très variées. De plus, les usagers sont de plus en plus mobiles et requièrent des applications sensibles au délai (voix, multimédia, etc.). Dans ce nouveau contexte de mobilité, la prochaine génération des réseaux sans fil (4G) s'annonce comme l'ultime solution visant à satisfaire les exigences des usagers tout en tirant profit de la complémentarité des services offerts par les systèmes mobiles existants. Pour ce faire, la principale vocation de la future génération (4G) consiste en l'intégration et la convergence des technologies sans fil existantes et celles à venir. Cette intégration passe obligatoirement par l'utilisation du protocole IP (Internet Protocol) qui permet de cacher l'hétérogénéité des systèmes intégrés puisqu'il demeure l'unique couche commune à toutes les plateformes mobiles. Plusieurs solutions d'intégration ont été proposées dans la littérature. Celles-ci concernent des architectures d'intégration et des mécanismes de gestion de mobilité. Cependant, les approches proposées ne font pas l'unanimité et souffrent de plusieurs handicaps liés, en particulier, à l'interopérabilité et la garantie des relèves sans coupures.----------ABSTRACT During the last few years, the use of wireless systems is becoming more and more popular. This tendency can be explained by the fact that mobile technologies are gaining in performance in terms of bandwidth, coverage and cost compared to the traditional wired solutions. However, each mobile network is tailored for a specific type of services and users. Moreover, end users are expected to become more and more mobile and show an increasing interest to real-time applications. In these circumstances, the next generation of mobile networks (4G) appears to be the ultimate solution that will satisfy mobile user demands and take benefit of the existing wireless systems. Indeed, the future generation consists of integrating, in an intelligent manner, the existing/future wireless systems in a way that users can obtain their services via the best available network. This integration passes through the use of the Internet Protocol (IP) that will hide the heterogeneity pertaining to the integrated networks. To deal with this very important task, several solutions are available in the literature. The proposed approaches cover some basic topics such as interworking architecture and mobility management. Nevertheless, these proposals suffer from drawbacks relevant to the guarantee of QoS through heterogeneous technologies

    Enhancement of packet reordering in a mobile stream control transmission protocol for a heterogeneous wireless network vertical handover

    Get PDF
    Future wireless access networks will be heterogeneous wireless network (HWN) environment which consists of various wireless technologies including universal mobile telecommunications system (UMTS) networks and wireless local area networks (WLAN). They are used together through vertical handover (VHO) to ensure global mobility and service continuity. The mobile stream control transmission protocol (mSCTP) layer supports dynamic association reconfiguration. This protocol allows mSCTP endpoints to dynamically add, change and delete IP addresses when the mobile node (MN) is switched between HWNs. During a mSCTP handover, the endpoints of the mSCTP are required to change the primary link from an old link to a UMTS into a new link to a WLAN. However, due to the disparity between UMTS/WLAN bandwidth, a packet reordering problem will occur when the MN of the mSCTP leaves to a new network. This packet reordering problem can then causes additional drawbacks such as impossibility of growing an mSCTP congestion window, unnecessary fast retransmissions, actual packet losses, and reduced efficiency of the receiving mSCTP. In this paper, we propose a packet reordering model (PRM) that is inserted inside the MN, and works as a special buffer of a large capacity with one input and one output port to receive all transmission sequence numbers (TSNs). It then forwards all incoming data chunks to the MN/WLAN networks after the VHO. The performance of the system is simulated and analyzed using NS-2 simulation tool. The simulation results show that the suggested model enhances the performance throughput and the congestion window of the conventional mSCTP through VHO by handling the packet reordering problem. In other words, the average performance throughout of the proposed PRM scheme is 181.48 Kbps or 16% increment compared to conventional mSCTP at 165.54 Kbps
    corecore