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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Towards the design of an energy-aware path selection metric for IEEE 802.11s wireless mesh network

Mhlanga, Martin Mafan January 2012 (has links)
Submitted in accordance with the requirements for the degree of Master of Arts in Communication Science at the University of Zululand, South Africa, 2012. / It is everyone’s dream to have network connectivity all the time. This dream can only be realised provided there are feasible solutions that are put in place for the next generation of wireless works. Wireless Mesh Networking (WMN) is therefore seen as a solution to the next generation of wireless networks because of the fact that WMNs configures itself and it is also self healing. A new standard for WMNs called the IEEE 802.11s is still under development. The protocol that is used by the IEEE 802.11s for routing is called Hybrid Wireless Mesh Protocol (HWMP). The main purpose of HWMP is to perform routing at layer-2 of the OSI model also referred to as the data link layer (DLL). Layer-2 routing is also referred to as the mesh path selection and forwarding. Devices that are compliant to the IEEE 802.11s standard will be able to use this path selection protocol. Devices that are manufactured by different vendors will therefore be interoperable. Even though significant efforts have gone into improving the performance of HWMP, the protocol still faces a lot of limitations and the most limiting factor is the small or restricted energy of the batteries in a wireless network. This is because of the assumption that mesh nodes that are deployed in urban areas tend to have no energy constraints while WMN nodes deployed in rural faces serious energy challenges. The latter relies on batteries and not on electricity supply which powers the WMN nodes in urban areas. This work, therefore, explores further the current trends towards maximising the network lifetime for the energy constrained networks. Hence the goal of this study is to design a path selection algorithm that is energyaware and optimising for the IEEE 802.11s based HWMP. The main idea is that paths with enough energy for transmission must be selected when transmitting packets in the network. Therefore, a simulation using NS-2 was carried out to assess the network performance of the proposed EAPM metric with the other metrics that have been analysed in literature including ETX. ETX has been used in WMNs but was not developed specifically for mesh. In conclusion, EAPM conserves more energy than the Multimetric, airtime link metric and lastly ETX. The simulation experiments show that EAPM optimises the energy used in the network and as a result EAPM has a prolonged network lifespan when comparing it to the rest of the metrics evaluated in this study. The results also revealed that the newly proposed EAPM exhibits superior performance characteristics even with regard to issues like end-to-end delay and packet delivery ratio. / CSIR Meraka Institute
2

Analysis of hardware requirements for airborne tactical mesh networking nodes / An analysis of tactical mesh networking hardware requirements for airborne mobile nodes

Milicic, Gregory J. 03 1900 (has links)
Approved for public release, distribution is unlimited / Wireless mesh mobile ad hoc networks (MANETs) provide the military with the opportunity to spread information superiority to the tactical battlespace in support of network-centric warfare (NCW). These mesh networks provide the tactical networking framework for providing improved situational awareness through ubiquitous sharing of information including remote sensor and targeting data. The Naval Postgraduate School's Tactical Network Topology (TNT) project sponsored by US Special Operations Command seeks to adapt commercial off the shelf (COTS) information technology for use in military operational environments. These TNT experiments rely on a variety of airborne nodes including tethered balloon and UAVs such as the Tern to provide reachback from nodes on the ground to the Tactical Operations Center (TOC) as well as to simulate the information and traffic streams expected from UAVs conducting surveillance missions and fixed persistent sensor nodes. Airborne mesh nodes have unique requirements that can be implemented with COTS technology including single board computers and compact flash. / Lieutenant, United States Navy
3

An analysis of the feasibility of implementing ultra wideband and mesh network technology in support of military operations

Herzig, Joseph F., Jr. 03 1900 (has links)
Approved for public release, distribution is unlimited / This thesis analyzes the feasibility, functionality, and usability of Ultra Wideband technology as an alternative to 802.11 in wireless mesh networks for multiple DoD contexts. Ultra wideband and wireless mesh network technologies and applications are researched and analyzed through multiple field and lab experiments for usability in current, real-world situations. Hardware and software investigations are conducted to determine any implementation issues between ultra wideband and wireless mesh networks. A detailed assessment is conducted of the various elements and operational constraints for developing an ultra wideband mesh network that can be utilized to improve situational awareness in network-centric operations. Through joint research with Lawrence Livermore National Laboratories, various hardware and software components are developed to create a test bed for tactical level ultra wideband and mesh networking experimentation in a highly mobile environment. This thesis also lays the groundwork into future ultra wideband and mesh networking applications. / Lieutenant, United States Navy
4

An analysis of network and sensor performance within IEEE 802.x wireless MESH networks in the Tactical Network Topology (TNT)

Davis, Joseph A., Sr. 03 1900 (has links)
Approved for public release, distribution is unlimited / The objective of this research is to analyze the network performance and sensor functionality, efficacy and usability of IEEE 802.x wireless MESH networks within a DoD Tactical network environment. Multiple sensor configurations operating with wireless MESH network technologies will be researched and analyzed for performance in expeditionary environment situations. Specifically, this thesis will attempt establish the foundation for the development of wireless MESH "network health" models by examining the performance of sensors operating within a MESH network and define which network performance metrics equate to good quality of service. This research will experiment with different application, sensor, and network configurations of currently available COTS components, such as, voice, video and data hardware. This thesis will lay the groundwork for wireless network MESH predictability, which will enable the optimal use of sensors within a tactical network environment. / Lieutenant Commander, United States Navy

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