Sharif Digital Repository

Although flooding and its variants are widely deployed for broadcasting by different applications, there are limited results on a complete and comprehensive analytical framework describing their behavior in general cases. We have previously published results which provide an upper bound for the performance of flooding when flooded packets have the highest serving priority. In this paper, using a different and simpler approach, we develop an analytical framework for analysis of flooding in general cases where flooding packets do not receive any special priority treatment in the network. The analysis is performed for a static multi-hop ad hoc wireless network using CSMA as its MAC layer. The... 

There are applications where important and critical data should be sent to all nodes in a wireless Ad-hoc network. Flooding and its variants are typically used to achieve this target. Network coding can also be used for broadcasting in such an environment. Energy consumption in the network, coverage and total delay are all important parameters that should be considered when an algorithm is evaluated. In this article, a reliable and energy efficient single source broadcasting algorithm is proposed based on network coding. This algorithm guarantees the delivery of desired messages to all network nodes, consumes less energy compared and reduces the total delay compared to other algorithms. This... 

Rate, energy and delay are three main parameters of interest in ad-hoc networks. In this paper, we discuss the problem of maximizing network utility and minimizing energy consumption while satisfying a given transmission delay constraint for each packet. We formulate this problem in the standard convex optimization form and subsequently discuss the tradeoff between utility, energy and delay in such framework. Also, in order to adapt for the distributed nature of the network, a distributed algorithm where nodes decide on choosing transmission rates and probabilities based on their local information is introduced. ©2009 IEEE  

Flooding and its variants are the simplest and most widely used broadcasting methods. Therefore, analysis of its performance in an ad-hoc environment using realistic assumptions is an important research topic. In this article, deploying a rigorous theoretic analysis, an upper bound on the performance of probabilistic flooding running over CSMA as a real and suitable MAC layer protocol for broadcasting scenarios is derived in a static multi-hop ad-hoc network in saturated condition. This model reveals the relation between network parameters and the performance of flooding and thus, helps the designer to have a better understanding of the effect of different design parameters. Using this... 

Flooding technique is widely using to manipulate sensor network essential activities such as synchronization, data gathering, network query and in-network information processing. Reliable and low latency data broadcasting is the primary goal in design of appropriate quality of service aware flooding algorithm. This paper proposes a new error-rate adaptive reliable data flooding strategy. Energy consumption which it the main limitation in sensor network, has been considered in optimal presented scheme. Also the tradeoff between reliability, power consumption and latency has been cared to achieve the finest devise. The simulation results have shown significant enhancement in quality of data... 

Many applications in wireless networks impose locally distributed traffic on the network. We consider the effect of traffic localization on throughput of large wireless networks in the scaling sense. We show that by careful exploitation of traffic localization, one can enhance the throughput of various schemes in wireless networks. Also, the important case of Small World traffic distribution in wireless networks is addressed. In this type of traffic, in addition to the local traffic, a non-negligible amount of global traffic should be handled by the network. It is shown that a non-negligible amount of network-wide traffic can be tolerated by network without any performance degradation in the... 

Although different broadcasting techniques are widely deployed in wireless networks, there are limited comprehensive analytical frameworks to evaluate the performance of such schemes. In this paper, based on a rigorous theoretical analysis, upper bounds on the network coverage and the total number of transmissions (corresponding to network energy consumption) of flooding and its popular variant probabilistic flooding are derived. The analysis is performed for a static multihop ad hoc wireless network when the network is in saturated condition. To consider a realistic medium-access control (MAC) layer algorithm, successful signal reception is based on the protocol model, and nodes employ... 

In this paper, we derive the rate of route discovery process for finding a randomly chosen destination in large wireless networks. The well-known protocol for route discovery is flooding in which each node simply rebroadcasts the route request packet once. Rate of route discovery process is defined as the inverse of time between transmitting two successive route request packets which shows how fast a node can request a route to its destination. Discovery time is another parameter of interest. For a single node discovering routes to its destination, at most the rate of Eθ (1/3√n) is feasible when n identical nodes are optimally placed in network area and the discovery time is of order... 

In this study, the authors propose a novel power allocation scheme in time division multiple access (TDMA)-based distributed multiple-input multiple-output (MIMO) channels. By modelling the problem with a TDMA MIMO interference channel, the authors have derived closed-form expressions for power and time slot assigned to each MIMO transmission. Although our scheme is sub-optimal, with the aid of Jensen's inequality, it is shown to be superior to solutions based on channel inversion. In addition, the proposed scheme is compared with the optimal solution, and also with the scheme proposed by Dohler. By applying our proposed power allocation to the hierarchical cooperation strategy, the authors... 

Mobile devices are equipped with a multi-core heterogeneous processing architecture to balance the trade-off between performance and power efficiency. To take advantage of this architecture, in this paper, we propose a task scheduling algorithm that allocates the cores to computation tasks and adjusts the cores' operating frequency by using the dynamic voltage and frequency scaling (DVFS) technique. Our objective is to minimize the battery energy consumption of devices. We also consider offloading the tasks to a cloud server to address their ever increasingly computation demand. In order to design the task scheduling algorithm, we first formulate a combinatorial optimization problem. To... 

We consider one-hop communication in wireless networks with random connections. In the random connection model, the channel powers between different nodes are drawn from a common distribution in an i.i.d. manner. In a wireless network with n nodes, a simple one-hop scheme achieving the throughput scaling of order n 1/3-δ, for any arbitrarily small δ > 0, is proposed. This scheme is based on maximizing the number of successful concurrent transmissions. Such achievable throughput, along with the order n 1/3 upper bound derived by Cui et al., characterizes the throughput of one-hop schemes for the class of connection models with distribution having finite mean and variance  

We consider the problem of determining throughput of one-hop unicast transmissions in ad hoc wireless networks. We consider an interference-limited scenario in which wireless links between different nodes are modeled by independently and identically distributed random variables. The main decoding challenge for receive nodes is due to interference of nonintended concurrent transmissions. In this scenario, we consider a heuristic one-hop transmission strategy based on activating source-destination pairs with strongest direct links and forcing other pairs to be silent. We present a closed-form expression for throughput scaling of such strategy, for a completely general channel power...