فهرست مقالات Ad hoc Networks

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  1 - Improvement of the mechanism of congestion avoidance in mobile networks
  Maryam Bagheri Bita Amirshahi Mehdi Khalili
  Mobile ad hoc network congestion control is a significant problem. Standard mechanism for congestion control (TCP), the ability to run certain features of a wireless network, several mutations are not common. In particular, the enormous changes in the network topology a چکیده کامل

  Mobile ad hoc network congestion control is a significant problem. Standard mechanism for congestion control (TCP), the ability to run certain features of a wireless network, several mutations are not common. In particular, the enormous changes in the network topology and the joint nature of the wireless network. It also creates significant challenges in mobile ad hoc networks (MANET), density is one of the most important limitations that disrupts the function of the entire network, after multi-path routing can load balance in relation to the single-path routing in ad hoc networks better, so the traffic division multiple routs congestion is reduced. This study is a multi-path load balancing and congestion control based on the speed of rate control mechanism to avoid congestion in the network provides communication flows. Given such a speed control method that is consistent is that the destination node copy speed is estimated at intermediate nodes and its reflection in the In the forward direction confirmation to the sender sends a packet, therefore the rate quickly estimate The results of the simulation has been set to demonstrate that a given method better package delivery speed and expanded capacity and density to be effective checks congestion control method is better than The result traditional. پرونده مقاله
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  2 - A Survey on Routing Protocols in Vehicular Ad hoc Network
  Elham Bozorgzadeh hamid barati Ali Barati
  Vehicular ad hoc networks (VANETs) are a subclass of mobile ad hoc networks (MANETs) that have inherited some of this type of network's features. Due to road accidents, these networks are a promising technology to increase passengers' comfort and safety and increase roa چکیده کامل

  Vehicular ad hoc networks (VANETs) are a subclass of mobile ad hoc networks (MANETs) that have inherited some of this type of network's features. Due to road accidents, these networks are a promising technology to increase passengers' comfort and safety and increase road safety and provide traffic information. In vehicular ad hoc networks, it is challenging to design an efficient routing protocol for data routing in vehicles due to rapid topology changes and frequent disconnections. Applications in these fields require efficient routing protocols. The design of a routing protocol must be done both in terms of useful information dissemination and under the information dissemination environment's actual conditions. In this paper, we overview the existing VANET routing protocols; As there are different routing protocols in VANET, we need to do detailed research on various routing protocols and their strengths/weaknesses. The routing protocols essentially concentrate on delay, packet delivery magnitude relation, information measure utilization, and plenty of alternative factors. However, there are challenges to select a routing protocol to a dynamic topology and special characteristics of VANETs. VANET is extremely advantageous because it helps in up the road safety through reducing the amount of accidents by warning drivers regarding the danger before they really face it and different facilities to comfort drivers. پرونده مقاله
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  3 - A fault tolerance routing protocol considering defined reliability and energy consumption in wireless sensor networks
  Hamid Hassan Kashi Amir Masoud Rahamni Mehdi Hoseinzadeh Vahid Sadatpour
  In wireless sensor networks, optimal consumptionof energy and having maximum life time are important factors. In this article attempt has been made to send the data packets with particular reliability from the beginning based on AODV protocol. In this way two new fields چکیده کامل

  In wireless sensor networks, optimal consumptionof energy and having maximum life time are important factors. In this article attempt has been made to send the data packets with particular reliability from the beginning based on AODV protocol. In this way two new fields add to the routing packets and during routing and discovering of new routes, the lowest remained energy of nodes and route traffic based on the number of discarded packages, will store in this field as two variables. These two variables will be considered during choosing a suitable route for sending the data to that message which should be answered by sink. The efficiency of this protocol is based on the fact that, at the route request, it finds the routes with high energy and low traffic through which data are sent(information is sent).So data packets reach the destination with a higher probability and also the balance of energy consumption is considered in the network. From the energy point of view, not using weak nodes routes leads to not having off nodes at the end of the process. This fact affects balancing of energy consumption and reducing the variance of the energy remainder proportional to AODV model. Not using high traffic routes leads to reducing collision and sending fewer signaling packets; more data packets with lower delay reach the destination. In the case of high congestion, for meeting the desired reliability, which is among the main goals there may be more sending signaling packets, delay and collision. But this happens with sending more packets and a guaranteed reliability. پرونده مقاله
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  4 - A Fuzzy Realistic Mobility Model for Ad hoc Networks
  Alireza Amirshahi Mahmoud Fathy Morteza Romoozi Mohammad Assarian
  Realistic mobility models can demonstrate more precise evaluation results because their parameters are closer to the reality. In this paper a realistic Fuzzy Mobility Model has been proposed. This model has rules which are changeable depending on nodes and environmental چکیده کامل

  Realistic mobility models can demonstrate more precise evaluation results because their parameters are closer to the reality. In this paper a realistic Fuzzy Mobility Model has been proposed. This model has rules which are changeable depending on nodes and environmental conditions. It seems that this model is more complete than other mobility models.After simulation, it was found out that not only considering nodes movement as being imprecise (fuzzy) has a positive effects on most of ad hoc network parameters, but also, more importantly as they are closer to the real world condition, they can have a more positive effect on the implementation of ad hoc network protocols. پرونده مقاله
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  5 - A New Intrusion Detection System to deal with Black Hole Attacks in Mobile Ad Hoc Networks
  Maryam Fathi Ahmadsaraei Abolfazl Toroghi Haghighat
  By extending wireless networks and because of their different nature, some attacks appear in these networks which did not exist in wired networks. Security is a serious challenge for actual implementation in wireless networks. Due to lack of the fixed infrastructure and چکیده کامل

  By extending wireless networks and because of their different nature, some attacks appear in these networks which did not exist in wired networks. Security is a serious challenge for actual implementation in wireless networks. Due to lack of the fixed infrastructure and also because of security holes in routing protocols in mobile ad hoc networks, these networks are not protected against attacks. For example in black hole attack, an attacker catches packets and throw them away, instead of forwarding them to their destinations. By using wireless intrusion detection systems, wireless networks can be protected. In this study, we introduce a new intrusion detection system to encounter black hole attack. This system is based on a combination of anomaly based intrusion detection (ABID) and specification based intrusion detection (SBID), we also use a new intrusion response. The analysis of simulation results (with NS-2) show that our method is success by using three measures: throughput, packet loss rate and packet delivery rate in comparing with ABID and SBID. پرونده مقاله
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  6 - A Survey of Solutions to Protect Against All Types of Attacks in Mobile Ad Hoc Networks
  Maryam Fathi Ahmadsaraei Abolfazl Toroghi Haghighat
  In recent years mobile networks have expanded dramatically, compared with other wireless networks. Routing protocols in these networks are designed with the assumption that there is no attacker node, so routing protocols are vulnerable to various attacks in these networ چکیده کامل

  In recent years mobile networks have expanded dramatically, compared with other wireless networks. Routing protocols in these networks are designed with the assumption that there is no attacker node, so routing protocols are vulnerable to various attacks in these networks. In this paper, we review the network layer attacks and then we simulate the impact of black hole attack on ad hoc on demand distance vector routing protocol with NS-2 simulation. Then we review all kinds of intrusion detection systems (IDS) in large and small mobile ad hoc networks. We simulate these networks when they are under single black hole attack and with the existence of IDS byNS-2 simulator software. Finally, we compared the results according to throughput, packet loss ratio and packet delivery rate with each other. پرونده مقاله
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  7 - یک رویکرد مقاوم و هوشمند برای پخش پیام در شبکه‌های موردی بین خودرو یی برای موارد اضطراری
  محمدصادق اژدری علی براتی حمید براتی
  شبکه‌های موردی بین خودرویی با هدف ایجاد ایمنی و راحتی برای رانندگان و مسافران ایجاد شده است. در این شبکه‌ها، تغییرات زیاد توپولوژی، چالش‌های زیادی را برای تحویل کارآمد داده‌ها ایجاد می‌کند. روش انتشار داده می‌تواند نیازهای پخش پیام اضطراری را برآورده کند. انتشار داده‌ها چکیده کامل

  شبکه‌های موردی بین خودرویی با هدف ایجاد ایمنی و راحتی برای رانندگان و مسافران ایجاد شده است. در این شبکه‌ها، تغییرات زیاد توپولوژی، چالش‌های زیادی را برای تحویل کارآمد داده‌ها ایجاد می‌کند. روش انتشار داده می‌تواند نیازهای پخش پیام اضطراری را برآورده کند. انتشار داده‌ها در این شبکه‌ها کاری پیچیده و مهم است زیرا تغییر زیاد سرعت ماشین‌ها، احتمال وجود شکاف‌های ارتباطی را بالا می‌برد. در این شبکه‌ها تحویل سریع و تضمینی بالای بسته‌ها دارای اهمیت بسیاری است. در این مقاله روشی پیشنهاد شده که در آن کانال ارتباطات برد کوتاه اختصاصی (DSRC) با سه نوع اولویت متفاوت برای پیام‌های ایمنی تقسیم ‌می‌گردد. جهت انتشار پیام برای هر کلاس یک گیرنده پویا تعریف می‌گردد، برای جلوگیری از انتشارات افزونه و استفاده بهینه از پهنای باند، شرط مابین بودن گره مبدأ و گره انتشار دهنده در نظر گرفته شده است. روش پیشنهادی به هیچ‌گونه سخت‌افزار یا کنترل کننده مرکزی نیاز ندارد. به منظور تحلیل میزان کارایی، روش پیشنهادی را با روش‌های تقسیم‌بندی و پخش برنامه‌ریزی‌شده تطبیقی (ASPBT) و پروتکل انتشار داده‌های انطباقی (AddP) مقایسه شده است. نتایج ارزیابی تحلیلی و شبیه‌سازی نشان می‌دهد که در روش پیشنهادی تاخیر در مقایسه با روش‌های ASPBT و AddP به ترتیب 5 درصد و 14 درصد کاهش یافته است. نرخ تحویل بسته در مقایسه با روش‌های AddP و ASPBT به ترتیب 37 درصد و 83/0 درصد بهبود یافته است. همچنین نرخ تصادم روش پیشنهادی 4 درصد و 11 درصد در مقایسه با روش‌های ASPBT و AddP بهبود یافته است. پرونده مقاله
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  8 - یک پروتکل مسیریابی مطمئن برای شبکه‌های خودرویی بی سیم
  محسن معدنی سید احمد معتمدی مصطفی محمدی
  ایجاد ارتباط مخابراتی بین خودروها و همچنین بین خودرو و تجهیزات کنار جاده‌ای، موسوم به شبکه‌های خودرویی بدون سازماندهی (VANET)، در سالهای اخیر به شدت مورد توجه قرار گرفته است. این شبکه‌ها به دلیل ویژگی دینامیک بودن و تغییرات سریع ساختار شبکه تا حدی شبیه شبکه‌های متحرک بد چکیده کامل

  ایجاد ارتباط مخابراتی بین خودروها و همچنین بین خودرو و تجهیزات کنار جاده‌ای، موسوم به شبکه‌های خودرویی بدون سازماندهی (VANET)، در سالهای اخیر به شدت مورد توجه قرار گرفته است. این شبکه‌ها به دلیل ویژگی دینامیک بودن و تغییرات سریع ساختار شبکه تا حدی شبیه شبکه‌های متحرک بدون سازماندهی (MANET) می‌باشند. تحرک سریع گره‌ها و همچنین محدودیتهای منابع شبکه، مسیریابی را به یکی از مشکلترین مباحث مطرح در VANET نموده است. بنابراین ارائه یک الگوریتم مسیریابی پایدار و مطمئن برای VANET، یکی از گامهای اساسی تحقق مخابرات خودرویی می‌باشد. در این مقاله، یک پروتکل مسیریابی دوگامه مبتنی بر الگوریتم AODV برای شبکه‌های خودرویی ارائه شده است. ابتدا گره‌ها با توجه به اطلاعات تحرک، مانند سرعت و جهت حرکت، دسته‌بندی می‌شوند. در صورت موفق نبودن مسیریابی، در گام دوم دسته‌بندی بر مبنای اطلاعات "طول عمر تخمینی لینک" (LET) صورت می‌گیرد. هدف پروتکل ارائه شده افزایش پایداری الگوریتم مسیریابی،به کمک انتخاب مسیرهایی با طول عمر بالا و کاهش قطعی مسیرهاست. نتایج شبیه سازی با NS-2 و مقایسه با الگوریتمهای DSR و AODV نشان می‌دهد که پروتکل پیشنهادی علاوه بر افزایش ضریب دریافت بسته‌های داده، سربار کنترلی مسیریابی را نیز کاهش می‌دهد. پرونده مقاله
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  9 - Routing in vehicular ad hoc networks using the proposed reinforcement learning method
  Faraein Aeini Hasan Sadati
  Today, with the equipping of vehicles and streets with wireless equipment, a new dynamic network called vehicle ad hoc network (VANET) is emerging. This network can support two types of communication: communication between one vehicle and another vehicle and contact bet چکیده کامل

  Today, with the equipping of vehicles and streets with wireless equipment, a new dynamic network called vehicle ad hoc network (VANET) is emerging. This network can support two types of communication: communication between one vehicle and another vehicle and contact between a vehicle and fixed means of communication around the streets. This network can be used in many fields such as safety, business, entertainment, and emergency. One of the main challenges in this network is the routing process to transfer information from one node to another. The main problem is the lack of a stable infrastructure. Of course, there is a problem in the MANET network that many algorithms and protocols have been presented to solve, but due to the high dynamics in these networks, these protocols cannot be used for VANET. Therefore, today the presentation and improvement of the protocol Routing features in VANET networks have become an attractive issue for researchers interested in computer networks. One of the challenging issues in these protocols is the possibility of adapting them to the high dynamics of the in-vehicle network. Of course, efforts have been made in recent years in this field, including artificial intelligence techniques. This paper also tried to improve sending rate and reduce latency by using the reinforcement learning method to select the nodes. To evaluate the protocol, its implementation has been done with OMNeT++ simulation. According to the obtained results and compared with other protocols such as GSR, the proposed protocol performs better in intercity networks. پرونده مقاله
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  10 - An Improved Method to Evaluate the Vehicle's Encounter with Events in the VANET with the Approach of Developing Non-Linear Methods
  farzaneh kaviani baghbadorani Mohammadreza Soltanaghaei
  10.30486/MJTD.1402.1104122
  Data exchange between vehicles as network nodes, like other ad-hoc networks, due to the lack of stability infrastructure and central management, and the complete distribution of the network platform, have led to attract many parts of today's researches. In this article, چکیده کامل

  Data exchange between vehicles as network nodes, like other ad-hoc networks, due to the lack of stability infrastructure and central management, and the complete distribution of the network platform, have led to attract many parts of today's researches. In this article, an improved method has been presented in order to evaluate the encounter of the vehicle with the incident, and the interaction of data related to the incidents for use in the vehicle ad-hoc networks. The proposed method has been developed based on the basic indicators of evaluating the node's encounter with events in vehicle ad-hoc networks and has been strengthened based on the advantages and capabilities of fuzzy logic, so that the desired and expected result is obtained from the output of the set. In order to evaluate the performance of the proposed method, developments and implements were based on the OPNET simulator and this method was compared with the VESPA and VESPA-DM methods as the most important researches in this field. The simulation results indicated the superiority of the proposed method over past researches. پرونده مقاله