12 research outputs found

    Cooperative-hierarchical based edge-computing approach for resources allocation of distributed mobile and IoT applications

    Get PDF
    Using mobile and Internet of Things (IoT) applications is becoming very popular and obtained researchers’ interest and commercial investment, in order to fulfill future vision and the requirements for smart cities. These applications have common demands such as fast response, distributed nature, and awareness of service location. However, these requirements’ nature cannot be satisfied by central systems services that reside in the clouds. Therefore, edge computing paradigm has emerged to satisfy such demands, by providing an extension for cloud resources at the network edge, and consequently, they become closer to end-user devices. In this paper, exploiting edge resources is studied; therefore, a cooperative-hierarchical approach for executing the pre-partitioned applications’ modules between edges resources is proposed, in order to reduce traffic between the network core and the cloud, where this proposed approach has a polynomial-time complexity. Furthermore, edge computing increases the efficiency of providing services, and improves end-user experience. To validate our proposed cooperative-hierarchical approach for modules placement between edge nodes’ resources, iFogSim toolkit is used. The obtained simulation results show that the proposed approach reduces network’s load and the total delay compared to a baseline approach for modules’ placement, moreover, it increases the network’s overall throughput

    Dinamička distribucija sigurnosnih ključeva i koalicijski protokol IP adresa za mobilne ad hoc mreže

    Get PDF
    In mobile adhoc networks (MANETs) a tree-based dynamic address auto-configuration protocol (T-DAAP) is one of the best protocols designed for address assignment as far as the network throughput and packet delays are concerned. Moreover, MANET security is an important factor for many applications given that any node can listen to the channel and overhear the packets being transmitted. In this paper, we merge the address assignment with the security key delivery into one protocol, such that a node in the MANET is configured with IP address and security key simultaneously. To the best of our knowledge, no single protocol provides concurrent assignment of IP addresses and security keys for MANET nodes. The proposed method, which is based on T-DAAP, shows significant enhancements in the required control packets needed for assigning network nodes IP addresses and security keys, MAC layer packets, total end-to-end delay, and channel throughput over those obtained when using separate protocols. Additionally, it provides not only efficient security keys to the nodes from the first moment they join the network, but also secure delivery of the address and security key to all participating nodes. It is noteworthy to mention that providing a complete security model for MANET to detect and countermeasure network security threats and attacks is beyond the scope of our proposed protocol.Kod mobilnih ad hoc mreža (MANET) dinamički protokol za autokonfiguraciju adresa baziran na stablu (T-DAAP) je jedan od najboljih protokola dizajniranih za dodjelu adresa iz perspektive propusnosti mreže i i kašnjenja paketa. štoviše, sigurnost MANET-a je važan faktor za mnoge aplikacije s obzirom da bilo koji čvor može osluškivati kanal i slučajno čuti pakete koji se šalju. U ovom radu, dodjela adresa i dostava sigurnosnih ključeva spojeni su u jedan protokol tako da je čvor u MANET-u konfiguriran simultano s IP adresom i sigurnosnim ključem. Prema saznanjima autora, niti jedan postojeći protokol ne pruža istovremeno dodjeljivanje IP adrese i sigurnosnog ključa za MANET čvorove. Predložena metoda, koja se bazira na T-DAAP-u, pokazuje značajna poboljšanja u odnosu na metode koje koriste odvojene porotokole, kod traženih kontrolnih paketa koji su potrebni za dodjeljivanje IP adresa i sigurnosnih ključeva čvorovima mreže, MAC paketa, ukupnog end-to-end kašnjenja i propusnosti kanala. Dodatno pruža ne samo efikasne sigurnosne ključeve čvorovima od trenutka kad se priključe mreži, nego i sigurno dostavljanje adrese i sigurnosnog ključa svim čvorovima koji sudjeluju u mreži. Važno je spomenuti da je pružanje cjelokupnog sigurnosnog modela za MANET koji detektira dodatno i protumjere prijetnjama i napadima na sigurnost mreže izvan dosega predloženog protokola

    The Role of Media and Islamic Criminal Legislation in Reducing Crime (From the perspective of students of the University of Jordan)

    Get PDF
    The study aimed to know the role of the media and its various styles, as well as the role of Islamic criminal legislation in reducing crime and identifying the obstacles that limit the effectiveness of the media in the prevention of crime. A random sample of 600 students was selected at different university levels at the University of Jordan, as well as personal background factors (independent variables): sex, place of residence, specialty, so that eleven different positions were identified, asking the respondents to determine their opinion on their respective trends. Keywords: Role, Media, Islamic Criminal Legislation, Crime DOI: 10.7176/JPCR/44-05 Publication date: September 30th 201

    A performance simulation for route maintenance in wireless ad hoc networks

    No full text
    A routing protocol in ad hoc wireless networks must take special consideration to link failure and route maintenance in order that the network services will not be interrupted. To decrease the link failure, Anticipated Route Maintenance Protocol (ARM) has been proposed. However, the detailed performance for this protocol has not been evaluated. In this paper, we have compared the performance of two protocols, standard Dynamic Source Routing Protocol (DSR) and a combination of DSR and ARM. The simulation results show how ARM improves the functionality of DSR by preventing the links in the route from breaking. Packets delivery ratio could be increased using ARM maintenance and achieved approximately 100% improvement. The simulations clarify also how ARM shows a noticeable improvement in dropped packets and links stability over DSR, even though there is more traffic and channel overhead in ARM. Copyright 2004 ACM

    Black hole attack in mobile ad hoc networks

    No full text
    The black hole problem is one of the security attacks that occur in mobile ad hoc networks (MANETs). We present two possible solutions. The first is to find more than one route to the destination. The second is to exploit the packet sequence number included in any packet header. Computer simulation shows that compared to the original ad hoc on-demand distance vector (AODV) routing scheme, the second solution can verify 75% to 98% of the route to the destination depending on the pause times at a minimum cost of the delay in the networks. Copyright 2004 ACM

    Performance Analysis of Dual-Hop AF Cognitive Relay Networks with Best Selection and Interference Constraints

    No full text
    In this paper, a dual-hop underlay cognitive relay network (CRN) with a best-relay selection (BRS) scheme under spectrum-sharing constraints from the primary user (PU) is investigated. The system model in this work consists of one PU, one secondary user (SU) and a few SU relays. Both users exchange the information using a half-duplex mode through amplify-and-forward (AF) SU relays. Moreover, all channels are modelled using the Nakagami-m fading model. In this work, the outage probabilities (OPs) are derived for the proposed system model under several scenarios to investigate the network performance under interference power constraint Ip at the PU receiver. In addition, the impacts of the number of relays and the channel fading severity parameters are investigated as well. Furthermore, the system performance is investigated for several PU locations. The various numerical results are verified using a Monte Carlo simulation. Overall, the obtained results show that several factors such as the number of relays, channel fading severity parameters and PU location have a major impact on the outage performance of the SU. The simulation and analytical results are perfectly matched, confirming the accuracy of the analytical derivations

    ARM: Anticipated route maintenance scheme in location-aided mobile ad hoc networks

    No full text
    Mobile ad hoc networks (MANET) are composed of moving wireless hosts which, within range of each other, form wireless networks. For communication to occur between hosts that are not within each other\u27s range, routes involving intermediate nodes must be established; however, since the hosts may be in motion, a host that was part of a route may move away from its upstream and downstream partners, thus breaking the route. In this paper, we propose anticipated route maintenance (ARM) protocol with two extensions to route discovery based routing scheme: Extend the route when nodes on a link move apart from each other and they have common neighbor that can be inserted in the path, and shrink route when a node discovers that one of its neighbor which is not the next hop is also on the same route several hops later on. By utilizing only local geographic information (now a part of some route finding algorithms), a host can anticipate its neighbor\u27s departure and, if other hosts are available, choose a host to bridge the gap, keeping the path connected. We present a distributed algorithm that anticipates route failure and performs preventative route maintenance using location information to increase a route lifespan. The benefits are that this reduces the need to find new routes (which is very expensive) and prevents interruptions in service. As the density of nodes increases, the chance to successfully utilize our route maintenance approach increases, and so does the savings. We have compared the performance of two protocols, pure dynamic source routing (DSR) protocol and DSR with ARM. The simulation results show how ARM improves the functionality of DSR by preventing the links in the route from breaking. Packets delivery ratio could be increased using ARM and achieved approximately 100% improvement. The simulations clarify also how ARM shows a noticeable improvement in dropped packets and links stability over DSR, even though there is more traffic and channel overhead in ARM

    The clinical value of peripheral immune cell counts in pancreatic cancer.

    No full text
    BackgroundElevated neutrophil-lymphocyte ratio (NLR) is linked to poor overall survival (OS) in pancreatic cancer. We aim to investigate the association of the various hematologic markers, in particular NLR among others, with distant metastases, a common feature in pancreatic cancer.MethodsClinical data from 355 pancreatic cancer patients managed at King Hussein Cancer Center (Amman-Jordan) have been reviewed. We examined the relationship between absolute neutrophil count (ANC), absolute lymphocyte count (ALC), absolute eosinophilic count (AEC), absolute monocytic count (AMC), NLR, monocyte to lymphocyte ratio (MLR) and platelet to lymphocyte ratio (PLR) with the presence of baseline distant metastases and OS. Receiver Operating Characteristic (ROC) curve analysis was plotted to identify the NLR optimum cutoff value indicative of its association with distant metastases.ResultsOn univariate and multivariate analyses patients whom on presentation had high NLR (≥3.3) showed more baseline distant metastases compared to patients with low NLR (ConclusionThis study presents additional evidence of the association of some of the hematologic markers; in particular ANC, NLR, AMC, and MLR, with baseline distant metastases and poor outcome in pancreatic cancer. Whether these immune phenomena can help in identifying patients at higher risk for the subsequent development of distant metastases is unknown
    corecore