@conference {
	title = {Aerial Platform Placement Algorithm to Satisfy Connectivity and Capacity Constraints in Wireless Ad-hoc Networks},
	author = {Perumal, Senni., Baras, John S.},
	year = {2008},
	month = {11/2008},
	abstract = {In this paper, we address the problem of establishing full connectivity and satisfying required traffic capacity between disconnected clusters in large wireless ad-hoc ground networks by placing a minimum number of advantaged high flying Aerial Platforms (APs) as relay nodes at appropriate places. We formulate the problem of providing both connectivity and required capacity between disconnected ground clusters as a constrained clustering problem with complexity costs. The basic requirement for connectivity between the ground clusters and APs is converted into a summation form distortion function. The additional requirement for connectivity between the various APs is encoded by adding a new (summation form) constraint to the distortion function. In order to satisfy the required capacity out of each cluster to all other clusters, we add a cost function that depends on the assignment probabilities of the APs and relate~the source (prior) probabilities of each cluster to the required capacity out of this cluster. The cost function produces solutions which are load balanced, i.e., the capacities supported through each AP are nearly equal. We solve the resultant clustering problem using Deterministic Annealing in order to find (near) globally optimal solutions for the minimum number and locations of the APs to establish full connectivity and provide required traffic capacity between disconnected clusters. We establish the validity of our algorithm by comparing it with optimal exhaustive search algorithms and show that our algorithm is near-optimal for the problem of establishing connectivity and satisfying capacity requirements between disconnected clusters.},
	address = {New Orleans, LA},
	booktitle = {IEEE Global Communications Conference (IEEE Globecom 2008)},
	pages = {pp. 1-5}
}
@conference {
	title = {Loss Network Models and Multiple Metric Performance Sensitivity Analysis for Mobile Wireless Multi-Hop Networks},
	author = {Baras, John S., Perumal, Senni., Tabatabaee, Vahid., Somasundaram, Kiran K., Purkayastha, Punyaslok.},
	year = {2008},
	month = {11/2008},
	abstract = {We develop and evaluate a new method for estimating and optimizing various performance metrics of mobile wireless multi-hop networks, including MANETs. The method utilizes approximate (throughput) loss model that couples the physical, MAC and routing layers effects. The model provides quantitative statistical relations between the loss parameters that are used to characterize multiuser interference and physical path conditions on the one hand and the traffic rates between origin-destination pairs on the other. The model considers effects of the hidden nodes, node scheduling algorithms, MAC and PHY layer failures and unsuccessful packet transmission attempts at the MAC layer in~arbitrary time-varying network topologies where multiple paths share nodes. The method then applies Automatic Di{\textregistered}erentiation (AD) to these implicit performance models, to compute sensitivities of various performance metrics with respect to net- work parameters. We demonstrate the method by applying it to time-varying mobile network topologies, including reduced connectivity instances, with both random access MAC (contention mode of the 802.11) as well as reservation-based MAC (USAP TDMA based protocol). We analyze throughput, delay and packet loss as metrics and investigate metric optimization and tradeoff analysis. Finally, we provide numerical results for realistic mobile networks with time-varying topologies.},
	address = {Maui, Hawaii},
	booktitle = {Fourth International Wireless Internet Conference (WICON 2008)}
}
@conference {
	title = {Aerial Platform Placement Algorithms to Satisfy Connectivity, Capacity and Survivability Constraints in Wireless Ad-hoc Networks},
	author = {Perumal, Senni., Baras, John S., Graff, Charles J., Yee, David G.},
	year = {2008},
	month = {11/2008},
	abstract = {In this paper, we address the problem of establishing full connectivity and satisfying required traffic capacity between disconnected clusters in large wireless ad-hoc ground networks by placing a minimum number of advantaged high flying Aerial Platforms (APs) as relay nodes at appropriate places. We also extend the connectivity solution in order to make the network survivable to a single AP failure. The problem of providing both connectivity and required capacity between disconnected ground clusters is formulated as a summation-form clustering problem with inter-AP distance constraints that make the AP network fully connected and with complexity costs that take care of cluster to AP capacity constraints. The resultant clustering problem is solved using Deterministic Annealing to find (near) globally optimal solutions for the minimum number and locations of the APs to establish full connectivity and provide required traffic capacity between disconnected clusters. In order to make the network single AP survivable, the connectivity solution is extended so that each AP connects to at least two neighboring APs and each ground cluster connects to at least two APs. We establish the validity of our algorithms by comparing it with optimal exhaustive search algorithms and show that our algorithms are near-optimal for the problem of establishing connectivity between disconnected clusters.},
	address = {San Diego, CA},
	booktitle = {Milcom: 08 Assuring Mission Success},
	pages = {pp. 1-7}
}
