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A new approach is presented for object based interprocess communication in this study. UNIX is a conventional operating system, and this study presents a new approach for representing processes as objects.Object based programming at the system level is discussed. The thesis presents motivation for supporting and implementing process objects with UNIX system calls, message passing and shared memory. Interprocess communication can be simulated using objects to represent processes.Related work in the area of system supported objects in conventional operating systems is also presented. / Department of Computer Science

Schedulers in optical switches are still electronic, the performance of these units has a significant impact on the performance of the network and could form a bottleneck in high speed networks, such as AAPN. Four time-slotted scheduling algorithms are investigated in this study, PIM, iSlip, PHM and Adapted-SRA. The study addresses the performance of AAPN for each of the algorithms, and evaluates the hardware complexity, estimating the running time of the algorithms. Performance measures were collected from an OPNET model, designed to emulate AAPN. Furthermore, hardware complexity and timing constraints were evaluated through hardware simulations, for iSlip, and through analysis for the rest of the algorithms. iSlip confirmed its feasibility by meeting the 10us timing constraint set by AAPN. The study revealed the superiority of iSlip and PHM over PIM and Adapted-SRA.

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Thesis (M.S.)--University of Hawaii at Manoa, 2006. / Includes bibliographical references (leaves 61-63). / ix, 63 leaves, bound ill. 29 cm

The Internet currently supports a best-effort connectivity service. There has been an increasing demand for the Internet to support Quality of Service (QoS) to satisfy stringent service requirements from many emerging networking applications and yet to utilize the network resources efficiently. However, it has been found that even with augmented QoS architecture, the Internet cannot achieve the desired QoS and furthermore, there are concerns about the scalability of any available QoS solutions. If the network is not provisioned adequately, the Internet is not capable to handle congestion condition. This is because the Internet is unaware of its internal network QoS states therefore it is not possible to provide QoS when the network state changes dynamically. This thesis addresses the following question: Is it possible to deliver the applications with QoS in the Internet fairly and efficiently while keeping scalability? In this dissertation we answer this question affirmatively by proposing an innovative service architecture: the Resource Discovery (RD) and Fair Intelligent Admission Control (FIAC) over scalable Internet. The main contributions of this dissertation are as follows: 1. To detect the network QoS state, we propose the Resource Discovery (RD) framework to provide network QoS state dynamically. The Resource Discovery (RD) adopts feedback loop mechanism to collect the network QoS state and reports to the Fair Intelligent Admission Control module, so that FIAC is capable to take resource control efficiently and fairly. 2. To facilitate network resource management and flow admission control, two scalable Fair Intelligent Admission Control architectures are designed and analyzed on two levels: per-class level and per-flow level. Per-class FIAC handles the aggregate admission control for certain pre-defined aggregate. Per-flow FIAC handles the flow admission control in terms of fairness within the class. 3. To further improve its scalability, the Edge-Aware Resource Discovery and Fair Intelligent Admission Control is proposed which does not need the core routers involvement. We devise and analyze implementation of the proposed solutions and demonstrate the effectiveness of the approach. For the Resource Discovery, two closed-loop feedback solutions are designed and investigated. The first one is a core-aware solution which is based on the direct QoS state information. To further improve its scalability, the edge-aware solution is designed where only the edges (not core)are involved in the feedback QoS state estimation. For admission control, FIAC module bridges the gap between 'external' traffic requirements and the 'internal' network ability. By utilizing the QoS state information from RD, FIAC intelligently allocate resources via per-class admission control and per-flow fairness control. We study the performance and robustness of RD-FIAC through extensive simulations. Our results show that RD can obtain the internal network QoS state and FIAC can adjust resource allocation efficiently and fairly.

The research recorded in this thesis tells the story of developing and implementing a user-centred intranet in the organisation where I work in a senior management position. My management support of the process led to adopting a networked model in our organisation, and also to my embracing the role of communications management.The organisation in which I work has a high rate of change and an entrepreneurial culture which is sometimes chaotic. This challenging environment was a good testing ground for the project, which sought to explore a number of propositions affirming the value of user-centred intranets.Developing and implementing the intranet encouraged collaboration amongst staff members. The intranet became a new channel of communication, which usefully enhanced the staff's ability to share and find out what was going on, who did what and how to contact them. My interventions as a manager, which occurred in parallel with the technological development of the intranet, led to spin-off organisational improvements such as an improved collaborative reporting system, the restructuring of the organisation manual files, and the establishment of a collaboratively-focussed full monthly staff meeting. Developing and implementing a user-centred intranet was a dynamic way to effect change in the organisation and orient it towards a networked organisational model, one which is communication rich, both collaborative and participative.The project was driven by my belief that a user-centred emphasis in intranet design is necessary in today's knowledge-based global economy, where there is a high rate of change. The networked organisational model should be embraced as a flexible model catering for change by promoting organic and dynamic networking within an organisation. This environment is communication-rich and collaborative, and a user-centred intranet is a communication channel well suited to support this model.A user-centred intranet should not be seen merely as an organisational artefact, but also as the a process of developing and implementing it will open up an organisation's culture, communication, and knowledge management in a participatory way. However, the degree that this will be achieved depends on a number of factors. For instance, the leaders of an organisation need to embrace a networked organisational model, encouraging and resourcing communication management for a culture of participation and collaboration.

Thesis (Ph. D.)--Rutgers University, 2007. / "Graduate Program in Computer Science." Includes bibliographical references (p. 156-165).