M Tech Dissertations

Permanent URI for this collectionhttp://ir.daiict.ac.in/handle/123456789/3

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    ItemOpen Access
    Analysis of address allocation protocols for mobile ad hoc networks
    (Dhirubhai Ambani Institute of Information and Communication Technology, 2011) Sati, Mohit; Srivastava, Sanjay; Divakaran, Srikrishnan
    In almost all networks, it is necessary to have a unique identifier for each node. This identifier is used to find out route locating a particular node. So an address is must for any node for unicast communication. Addresses can be preconfigured manually or can be assigned dynamically using a server (e.g. DHCP server). Manual configuration of ad hoc network is not possible for large scale networks. And setting up a server is not possible due to lack of infrastructure in Ad Hoc Networks. So it is necessary to have a mechanism by which we can allocate addresses to the nodes dynamically without any prior setup. Lack of infrastructure and mobility of nodes makes address allocation a challenging task in MANET. We present worst case message complexity analysis of a number of proposed address allocation protocols, which can be useful for estimating upper bounds for overhead and latency involved in address allocation as well as partitioning and merging. We also show that the worst case analysis is not a useful indicator of real world performance of the protocols. Buddy approach [5] is one of the many proposed approaches for address allocation. We model DPDA (A Distributed Protocol for Dynamic Address assignment in mobile ado networks)[6], a protocol based on buddy approach, to estimate the overhead involved in address allocation. We conduct simulations in NS-2 and compare with analytical results to validate our model. We perform simplified simulations using Python script which also validates the proposed model. We also do a simulation based comparison of MANETconf (MANET configuration) [8] and DPDA[6] in term of overhead and latency in address allocation, which shows that DPDA causes lower communication overhead and latency than Manetconf.
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    ItemOpen Access
    Scalable routing in mobile ad hoc networks
    (Dhirubhai Ambani Institute of Information and Communication Technology, 2009) Patel, Brijesh; Srivastava, Sanjay
    In Mobile Ad Hoc Networks (MANETs), performing routing is a challenging task in presence of the varying network parameters like node mobility, traffic and network size. It is very important to analyze the scalability characteristics of the routing protocols with respect to these parameters. ZRP is considered to be one of the most scalable routing protocols due to its multiscoping and hybridization features. We propose a general, parameterized model for analyzing control overhead of ZRP. A generic probabilistic model for data traffic is also proposed which can be replaced by different traffic models. Our analytical model is validated by comparisons with simulations performed on different scenarios. In our simulation results we have observed that the optimal zone radius lies where the proactive and reactive overhead components of ZRP are approximately equal as observed in [19]. We have also observed that optimal zone radius setting is different under different network conditions. Our simulations show that as the mobility increases the optimal zone radius value decreases, and as the traffic increases the value of optimal zone radius increases. Moreover, if a node operates away from the optimal zone radius setting then it has to bear and ditional routing overhead. Our simulations show that this deviation is quite high in case of low mobility (upto 35%) than in high mobility (upto 23%).
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    ItemOpen Access
    Analysis of address allocation protocols for mobile ad hoc networks
    (Dhirubhai Ambani Institute of Information and Communication Technology, 2009) Sheth, Kavan J.; Srivastava, Sanjay
    In almost all networks, it is necessary to have a unique identifier for each node. This identifier is used to find out route locating a particular node. So an address is must for any node for unicast communication. Addresses can be preconfigured manually or can be assigned dynamically using a server (e.g. DHCP server). Manual configuration of ad hoc network is not possible for large scale networks. And setting up a server is not possible due to lack of infrastructure in Ad Hoc Networks. So it is necessary to have a mechanism by which we can allocate addresses to the nodes dynamically without any prior setup. Lack of infrastructure and mobility of nodes makes address allocation a challenging task in MANET. We present worst case message complexity analysis of a number of proposed address allocation protocols, which can be useful for estimating upper bounds for overhead and latency involved in address allocation as well as partitioning and merging. We also show that the worst case analysis is not a useful indicator of real world performance of the protocols. Buddy approach [5] is one of the many proposed approaches for address allocation. We model DPDA (A Distributed Protocol for Dynamic Address assignment in mobile ado networks)[6], a protocol based on buddy approach, to estimate the overhead involved in address allocation. We conduct simulations in NS-2 and compare with analytical results to validate our model. We perform simplified simulations using Python script which also validates the proposed model. We also do a simulation based comparison of MANETconf (MANET configuration) [8] and DPDA[6] in term of overhead and latency in address allocation, which shows that DPDA causes lower communication overhead and latency than Manetconf.
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    ItemOpen Access
    Buffer aware routing in interplanetary ad hoc network
    (Dhirubhai Ambani Institute of Information and Communication Technology, 2007) Mistry, Kamal; Srivastava, Sanjay; Lenin, R. B.
    Recent research has shown that existing TCP/IP protocol suit exhibits poor performance in space communication networks. To deal with communication challenges in deep space such as long propagation delay, high channel error rate, limited bandwidth etc. the architecture called Interplanetary Ad hoc Network (IPAN) is envisioned to establish a communication infrastructure in environment which allows to connect planets, natural and artificial satellites, and various mission elements such as space- crafts and rovers. The communication links in IPANs possess the properties of low bandwidth, high error rate, high latency and link unavailability for longer period of time. Nodes in such networks are resource constrained in terms of storage, energy and processing power. This work proposes a probabilistic routing protocol called \Buffer Aware Routing Protocol in Interplanetary Ad hoc Network (BARPIN)" based on the store and forward principle of Delay Tolerant Networking (DTN). Here IPAN is modeled as the network of two kinds of nodes, one having deterministic mobility patterns with greater resources and the others having random movement patterns with limited resources in terms of storage and energy. The delivery ratio performance measure of BARPIN is studied for different network conditions by changing field sizes, traffic rates, available resources on various nodes and for different source-destination pairs. Further we propose a model to estimate the minimum required buffer size of nodes for different data rates to reduce the packet loss due to buffer overflow, and justified the simulation results with analytical results.