The Experts below are selected from a list of 12 Experts worldwide ranked by ideXlab platform
Brian D. Haynes - One of the best experts on this subject based on the ideXlab platform.
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Technology Candidates for Air-to-Air and Air-to-Ground Data Exchange
2015Co-Authors: Brian D. HaynesAbstract:Technology Candidates for Air-to-Air and Air-to-Ground Data Exchange is a two-year research effort to visualize the U. S. aviation industry at a point 50 years in the future, and to define potential communication solutions to meet those future data exchange needs. The research team, led by XCELAR, was tasked with identifying future National Airspace System (NAS) scenarios, determining requirements and functions (including gaps), investigating technical and business issues for air, ground, & air-to-ground interactions, and reporting on the results. The project was conducted under technical direction from NASA and in collaboration with XCELAR's partner, National Institute of Aerospace, and NASA technical representatives. Parallel efforts were initiated to define the information exchange functional needs of the future NAS, and specific communication link technologies to potentially serve those needs. Those efforts converged with the mapping of each identified future NAS function to potential enabling communication solutions; those solutions were then compared with, and ranked relative to, each other on a technical basis in a structured analysis process. The technical solutions emerging from that process were then assessed from a business case perspective to determine their viability from a real-world adoption and Deployment Standpoint. The results of that analysis produced a proposed set of future solutions and most promising candidate technologies. Gap analyses were conducted at two points in the process, the first examining technical factors, and the second as part of the business case analysis. In each case, no gaps or unmet needs were identified in applying the solutions evaluated to the requirements identified. The future communication solutions identified in the research comprise both specific link technologies and two enabling technologies that apply to most or all specific links. As a result, the research resulted in a new analysis approach, viewing the underlying architecture of ground-air and air-air communications as a whole, rather than as simple "link to function" paired solutions. For the business case analysis, a number of "reference architectures" were developed for both the future technologies and the current systems, based on three typical configurations of current aircraft. Current and future costs were assigned, and various comparisons made between the current and future architectures. In general, it was assumed that if a future architecture offers lower cost than the current typical architecture, while delivering equivalent or better performance, it is likely that the future solution will gain industry acceptance. Conversely, future architectures presenting higher costs than their current counterparts must present a compelling benefit case in other areas or risk a lack of industry acceptance. The business case analysis consistently indicated lower costs for the proposed future architectures, and in most cases, significantly so. The proposed future solutions were found to offer significantly greater functionality, flexibility, and growth potential over time, at lower cost, than current systems. This was true for overall, fleet-wide equipage for domestic and oceanic air carriers, as well as for single, General Aviation (GA) aircraft. The overall research results indicate that all identified requirements can be met by the proposed solutions with significant capacity for future growth. Results also illustrate that the majority of the future communication needs can be met using currently allocated aviation RF spectrum, if used in more effective ways than it is today. A combination of such optimized aviation-specific links and commercial communication systems meets all identified needs for the 50-year future and beyond, with the caveat that a new, overall function will be needed to manage all information exchange, individual links, security, cost, and other factors. This function was labeled "Delivery Manager" (DM) within this research. DM employs a distributed client/server architecture, for both airborne and ground communications architectures. Final research results included identifying the most promising candidate technologies for the future system, conclusions and recommendations, and identifying areas where further research should be considered.
Brett Chapman - One of the best experts on this subject based on the ideXlab platform.
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Deploying QoS for Cisco IP and Next Generation Networks: The Definitive Guide
2009Co-Authors: Vinod Joseph, Brett ChapmanAbstract:Deploying QoS for IP Next Generation Networks: The Definitive Guide provides network architects and planners with insight into the various aspects that drive QoS Deployment for the various network types. It serves as a single source of reference for businesses that plan to deploy a QoS framework for voice, video, mobility and data applications creating a converged infrastructure. It further provides detailed design and implementation details for various service Deployments across the various Cisco platforms such as the CRS-1, 12000, 7600 & 7200 series routers that are widely deployed in most Carrier Networks. The book covers architectural and implementation specific information plus recommendations for almost all the popular line cards across the various hardware platforms widely used in the market. It also addresses QoS architecture and Deployment on the Cisco CRS-1 platform and is considered as a unique selling point of this book. In short the books serve as an "On the Job Manual" which can also be used as a study guide for Cisco specialist certification programs (CCNA, CCIP, CCIE) This book will includes detailed illustration and configurations. In addition, it provides detailed case studies along with platform specific tests and measurement results. A link to a detailed tutorial on QoS metrics and associated test results will be available at the book's companion website in order to ensure that the reader is able to understand QoS functionality from a Deployment Standpoint. Covers the requirements and solutions in deploying QoS for voice, video, IPTV, mobility and data traffic classes (Quad-play networks), saving the reader time in searching for hardware specific QoS information, given the abundance of Cisco platforms and line cards. Presents real-life Deployments by means of detailed case studies, allowing the reader to apply the same solutions to situations in the work place. Provides QoS architecture and implementation details on Cisco CRS-1, 12000, 7600, and 7200 routing platforms using Cisco IOS/IOS-XR software, aiding the reader in using these devices and preparing for Cisco specialist certification.
Vinod Joseph - One of the best experts on this subject based on the ideXlab platform.
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Deploying QoS for Cisco IP and Next Generation Networks: The Definitive Guide
2009Co-Authors: Vinod Joseph, Brett ChapmanAbstract:Deploying QoS for IP Next Generation Networks: The Definitive Guide provides network architects and planners with insight into the various aspects that drive QoS Deployment for the various network types. It serves as a single source of reference for businesses that plan to deploy a QoS framework for voice, video, mobility and data applications creating a converged infrastructure. It further provides detailed design and implementation details for various service Deployments across the various Cisco platforms such as the CRS-1, 12000, 7600 & 7200 series routers that are widely deployed in most Carrier Networks. The book covers architectural and implementation specific information plus recommendations for almost all the popular line cards across the various hardware platforms widely used in the market. It also addresses QoS architecture and Deployment on the Cisco CRS-1 platform and is considered as a unique selling point of this book. In short the books serve as an "On the Job Manual" which can also be used as a study guide for Cisco specialist certification programs (CCNA, CCIP, CCIE) This book will includes detailed illustration and configurations. In addition, it provides detailed case studies along with platform specific tests and measurement results. A link to a detailed tutorial on QoS metrics and associated test results will be available at the book's companion website in order to ensure that the reader is able to understand QoS functionality from a Deployment Standpoint. Covers the requirements and solutions in deploying QoS for voice, video, IPTV, mobility and data traffic classes (Quad-play networks), saving the reader time in searching for hardware specific QoS information, given the abundance of Cisco platforms and line cards. Presents real-life Deployments by means of detailed case studies, allowing the reader to apply the same solutions to situations in the work place. Provides QoS architecture and implementation details on Cisco CRS-1, 12000, 7600, and 7200 routing platforms using Cisco IOS/IOS-XR software, aiding the reader in using these devices and preparing for Cisco specialist certification.
Yan Yao - One of the best experts on this subject based on the ideXlab platform.
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feasibility of optimally assigning channels by exhaustive search in commercial multi radio wireless mesh networks
Telecommunication Systems, 2010Co-Authors: Wei Xie, Ying Jun Zhang, Mihail L Sichitiu, Yan YaoAbstract:Channel assignment problems in multi-radio wireless mesh networks (WMNs) have been shown to be NP-hard in various scenarios in the literature. By far, most of research efforts have focused on developing efficient approximation algorithms that run reasonably fast and provide good quality channel assignment rather than the optimal one. However, from the practical network design and Deployment Standpoint, engineers care more about whether it is feasible to optimally assign channels in the simplest way (i.e., exhaustive search), as most of existing commercial WMNs are of small/medium scale. In this paper, we attempt to answer this practical question. We study the complexity of general channel assignment problems with certain basic and common properties. The results show that the complexity in terms of the number of different possible assignments is exponential in the number of wireless links. Furthermore, we estimate the theoretical runtime of determining the optimal channel assignment by exhaustive search and validate it through experiments. We show that, given certain computing power (e.g., an off-the-shelf notebook PC), it is feasible to optimally solve channel assignment problems in small-scale and medium-scale commercial multi-radio WMNs. In other words, approximation algorithms are not needed for most of current commercial WMNs.
Wei Xie - One of the best experts on this subject based on the ideXlab platform.
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feasibility of optimally assigning channels by exhaustive search in commercial multi radio wireless mesh networks
Telecommunication Systems, 2010Co-Authors: Wei Xie, Ying Jun Zhang, Mihail L Sichitiu, Yan YaoAbstract:Channel assignment problems in multi-radio wireless mesh networks (WMNs) have been shown to be NP-hard in various scenarios in the literature. By far, most of research efforts have focused on developing efficient approximation algorithms that run reasonably fast and provide good quality channel assignment rather than the optimal one. However, from the practical network design and Deployment Standpoint, engineers care more about whether it is feasible to optimally assign channels in the simplest way (i.e., exhaustive search), as most of existing commercial WMNs are of small/medium scale. In this paper, we attempt to answer this practical question. We study the complexity of general channel assignment problems with certain basic and common properties. The results show that the complexity in terms of the number of different possible assignments is exponential in the number of wireless links. Furthermore, we estimate the theoretical runtime of determining the optimal channel assignment by exhaustive search and validate it through experiments. We show that, given certain computing power (e.g., an off-the-shelf notebook PC), it is feasible to optimally solve channel assignment problems in small-scale and medium-scale commercial multi-radio WMNs. In other words, approximation algorithms are not needed for most of current commercial WMNs.