Virtual Cell Layout Based Dynamic Source Routing (vb-dsr) For The Mobile Subsystem Of The Next Generation Tactical Communications Systems

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2002Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2002Telsiz ağlar, 1970’lerde ortaya çıkışlarından itibaren bilgisayar endüstrisinde çok yaygınlaşmıştır. Telsiz ağlar gezgin kullanıcılara nerede olduklarına bağlı olmadan heryerde iletişim kurma ve bilgiye erişim imkanı sağlar. Hiçbir sabit altyapıya gerek duymadan bu imkanı sağlayan ad hoc ağların zaman içinde gelişmesiyle ve askeri, ticari ve özel maksatlar için tercih edilir hale gelmesiyle, uygulamada bazı zorluklar başgöstermiştir. Çalışmamızda, bu zorlukları ve ad hoc ağlardan beklenenleri dikkate alarak Sanal Hücre Kalıbı (SHK) tabanlı Dinamik Kaynak Yol Atama (DKYA) yaklaşımını bir çözüm olarak sunuyoruz. SHK, etkili bir özkaynak yönetimi ve ağ ölçeklenebilirliği sağlayan çok-katmanlı öbek-yapılı bir yaklaşımdır. Biz SHK yapısının üzerine Dinamik Kaynak Yolatama protokolunu uyguladık. Sunduğumuz yaklaşım, SHK yapılı DKYA, iki düzeyli hiyerarşik öbek yapılı bir sistemdir. SHK yaklaşımında önerilen benzetim yaklaşımını geliştiriyoruz ve taktik iletişimlerin başarımlarının değerlendirmesinde bu benzetim yaklaşımını kullanıyoruz. Bu yöntemde, önceden gerçekleştirilen bilgisayar destekli askeri tatbikatlarda girilen emirleri, çok sayıdaki birliğe ait hareket, görev ve durum gibi verileri toplayan bir yapıcı (muharebe) model kullanarak tekrar işlemekteyiz. Daha sonra toplanan bu veriler daha da detaylandırılarak, başarı ölçütlerimize ait değerleri üreten benzetim kullanılmaktadır. Sistemi değerlendiren başarım ölçütleri, SHK-tabanlı DKYA’nın gezgin ad hoc ağlardan beklenenleri sağladığını göstermektedir.Wireless networks have become very popular in the computing industry after their emergence in the 1970’s. Wireless networks provide mobile user with ubiquitous communication capability and information access regardless of location. Mobile ad hoc networks, that manage it without a need to infrastructure networks, as evolved in time, exhibit some challenges to implement as they become more preferable for military, commercial and special purposes. By considering the challenges and expectations of mobile ad hoc networks, we propose an approach called VCL based DSR (VB-DSR), which uses Dynamic Source Routing (DSR) protocol over Virtual Cell Layout (VCL) structure. VCL is a multi-tier cluster-based approach that provides an efficient resource management and network scalability. We implemented Dynamic Source Routing protocol over VCL structure. Proposed approach, VB-DSR, is a cluster-based two level hierarchical scheme. We also enhance the simulation approach proposed by VCL structure, and use it for the evaluation of tactical communication systems. In this approach, the commands entered during the military computer aided exercises are replayed by running a constructive (combat) model which generates mobility, posture and status data for a number of units, then these data are enhanced and drive a simulation which produces the data related to the performance metrics. The evaluated performance of the system shows that VB-DSR approach satisfies the requirements of mobile ad hoc networks.Yüksek LisansM.Sc

Enhancing Cooperation in MANET Using the Backbone Group Model (An Application of Maximum Coverage Problem)

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Effective bootstrapping of Peer-to Peer networks over Mobile Ad-hoc networks

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