Thesis (M.S.)--Rochester Institute of Technology, 1984. / Typescript. Includes bibliographical references (p. 71).

Thesis (Ph. D.)--University of Texas at Austin, 1998. / Vita. Includes bibliographical references (leaves 237-254). Available also in a digital version from Dissertation Abstracts.

In a distributed model of intelligence, peer components need to communicate with one another. I present a system which enables two agents connected by a thick twisted bundle of wires to bootstrap a simple communication system from observations of a shared environment. The agents learn a large vocabulary of symbols, as well as inflections on those symbols which allow thematic role-frames to be transmitted. Language acquisition time is rapid and linear in the number of symbols and inflections. The final communication system is robust and performance degrades gradually in the face of problems.

Dimitri P. Bertsekas, Eli M. Gafni, Robert G. Gallager. / Bibliography: p. 47. / "March 1981" / " ARPA Grant No. ONR-N00014-75-C-1183" "National Science Foundation Grant NSF/ECS 79-19880"

M. Tech. Electrical Engineering. / High-speed transmission network requires adequate synchronization planning for quality of service. Based on ITU-T synchronization network guidelines, this dissertation proposes a Synchronous Digital Hierachy (SDH) synchronization model catering for loop of synchronization and robust to communications links faults. From candidate schemes for providing synchronization information, we have adopted the master-slave strategy. Heuristics have been developed to assist in the allocation of primary and back-up reference clocks. The contribution lies in the systematic selection of master node placement, the distribution of the reference clock from master node to all slave nodes using shortest path and the allocation of system redundancy by means of clock priority table for each nodal clock. To cater for clock stability and accuracy, the use of atomic clock (Cesium, Rubidium) as frequency standard, in long term basis, has proven that clock s characteristics namely stability and accuracy may be controlled in the midst of jitter/wander. Fiber optics transmission medium has proven to be adequate for optimal clock dissemination with very trivial frequency deviation from the nominal positional instant, traceable to Primary Reference Clock.

There has been a recent paradigm shift in the study of animal communication from examining interactions as dyads to considering interactions as occurring in a communication network. The dawn chorus of songbirds, a striking acoustic phenomenon, provides an ideal opportunity to study network communication because multiple singers are within range of each other, permitting eavesdropping by both males and females. I used a 16-microphone Acoustic Location System (ALS) to simultaneously record and analyse the dawn chorus in a population of black-capped chickadees (Poecile atricapillus) breeding in eastern Ontario. Males frequency-match neighbours 24% of the time at dawn, more often than expected by chance or during daytime singing interactions. The amount of matching between males from different over-wintering flocks is significantly greater than between flockmates. Males of the same winter dominance rank match significantly more than do males of disparate ranks. Male black-capped chickadees are interacting vocally with neighbours at dawn, using the dawn chorus to mediate social relationships in ways that suggest useful information is available to the network of male and female receivers. Matching levels are not related to distance between opponents. However, males with non-fertile mates move over larger areas while chorusing and are further from their nest than males with fertile mates, suggesting dawn mate guarding. Males with non-fertile mates spend more of their chorus near boundaries with fertile neighbours than non-fertile neighbours possibly positioning themselves to facilitate eavesdropping by fertile females. Male chickadees of high and low winter social rank do not differ in either the size of their communication network, or the way they use their songs when interacting with neighbours. Males match multiple neighbours both sequentially and simultaneously. Simultaneous matching is most often the result of a former flockmate joining an interaction between two males who had been in different winter flocks. High-ranked males join the interactions of their lower-ranked flockmates, preferentially when those males are matching other high-ranked males. The dawn chorus is an interactive communication network in which all males participate and is characterized by interactions between multiple senders and receivers with males eavesdropping on interactions in which they are not involved. / Thesis (Ph.D, Biology) -- Queen's University, 2008-09-17 15:07:56.276

by Dimitri P. Bertsekas, Eli M. Gafni, Robert G. Gallager. / Bibliography: p. 34-35. / "October, 1983." / Defense Advanced Research Projects Agency Grant No. ONR-N00014-75-C-1183 National Science Foundation Grant NSF/ECS 79-19880

Magister Scientiae - MSc / This thesis shows that mobility management protocols for infrastructure Internet may be used in a wireless mesh network environment. In this research Mobile IPv6 and Fast Handover for Hierarchical Mobile IPv6 are successfully implemented in a wireless mesh network environment. Two experiments were carried out: vertical and horizontal handover simulations. Vertical handover simulation involved a heterogeneous wireless environment comprising both wireless local area and wireless mesh networks. An OPNET Mobile IPv6 model was used to simulate the vertical handover experiment. Horizontal handover simulation involved Mobile IPv6 and Fast Handover for Hierarchical Mobile IPv6 applied in ns2 wireless mesh network. The vertical handover results show that MIPv6 is able to manage vertical handover between wireless local area and wireless mesh network. The horizontal handover results illustrate that in mesh networks, Fast Handover for Hierarchical Mobile IPv6's performance is superior to Mobile IPv6. Fast Handover for Hierarchical Mobile IPv6 generates more throughput and less delay than Mobile IPv6. Furthermore, Fast Handover for Hierarchical Mobile IPv6 drops less data packets than Mobile IPv6. The simulations indicate that even though there are multi-hop communications in wireless mesh networks, the performance of the multi-hop routing may not play a big role in the handover performance. This is so because the mesh routers are mostly static and the multi-hop routes are readily available. Thus, the total handover delay is not affected too much by the WMN hops in the paths for signaling message transmission. / South Africa

The foreseen massive deployment of the internet of things (IoT) is expected to suffer from high security risks. This mainly results from the difficulty to monitor and cure the IoT devices in such large-scale deployment. In this thesis, we propose a spatial random deployment of special nodes (firewalls) which can detect and cure infected nodes within certain radius. An important concern is to add sufficient number of firewalls to make an epidemics finite and, hence, prevent malware outbreak over the whole network. The problem will be analyzed using percolation theory. Namely, we derive an upperbound for the critical intensity of spatial firewalls which guarantees prevention of large-scale network epidemics, regardless of the intensity of regular nodes. Using tools from percolation theory, we analyze the proposed solution and show the conditions required to ensure its efficiency.

This thesis poses and solves a distribution free learning problem with consensus that arises in the study of estimation and control strategies for distributed sensor networks. Each node i for i = 1, . . . , n of the sensor network collects independent and identically distributed local measurements {z i} := {z i j}j∈N := {(x i j , yi j )}j∈N ⊆ X × Y := Z that are generated by the probability measure ρ i on Z. Each node i for i = 1, . . . , n of the network constructs a sequence of estimates {f i k }k∈N from its local measurements {z i} and from information functionals whose values are exchanged with other nodes as specified by the communication graph G for the network. The optimal estimate of the distribution free learning problem with consensus is cast as a saddle point problem which characterizes the consensus-constrained optimal estimate. This thesis introduces a two stage learning dynamic wherein local estimation is carried out via local least square approximations based on wavelet constructions and information exchange is associated with the Lagrange multipliers of the saddle point problem. Rates of convergence for the two stage learning dynamic are derived based on certain recent probabilistic bounds derived for wavelet approximation of regressor functions. / Master of Science