Measurement studies of Internet performance are critical for validating or refuting widely held beliefs about Web behavior, and for shedding light on unknown behaviors. Results from these studies can guide Internet architects in making decisions that affect Internet Service Providers (ISPs), content providers and end-users. Examples of decisions that can benefit from measurement information include provisioning network capacity, placing Domain Name System (DNS) and Web servers, and tuning parameters of transport layer protocols. Internet protocols and services may exhibit different performance characteristics when observed from different locations in the Internet topology; to date, however, there has been little work investigating the differences in these characteristics from multiple vantage points. Typically, performance studies present results of measurements taken in only one or two locations. Some of the reasons for the lack of work in this area are the following. First, performance measurement was not a high priority of Internet design and was not built into the network architecture. Second, it is difficult to obtain the necessary level of privilege at many different locations in the Internet topology to perform measurement studies. Finally, high expectations for real-time Internet performance is a relatively recent phenomenon. In this thesis we develop several methods for gathering Internet performance data from multiple locations throughout the world, and to analyze data gathered. Our focus is on the protocols and services that support the World Wide Web. In the first method we utilize a modified Web proxy. Our proxy captures and logs fine-grained performance information on a per-user basis. Our second method is to create and deploy a measurement package for examining DNS performance. We modified the BIND DNS server and packaged it with a script to drive the data collection. Our final method is to create and distribute an application to be run at user sites worldwide. One of the primary tasks of the application is to provide performance data from each instance of the application executing at locations throughout Internet topology. We can use the information provided by this application to examine user-perceived Internet performance throughout the globe.

No description available.

Thesis (M.S.)--State University of New York at Binghamton, Dept. of Electrical & Computer Engineering, 2006. / Includes bibliographical references.

published_or_final_version / Electrical and Electronic Engineering / Doctoral / Doctor of Philosophy

Ho Siu Ting. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 84-87). / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Drivers for performance monitoring --- p.1 / Chapter 1.2 --- Migration of performance monitoring --- p.1 / Chapter 1.3 --- OPM categories --- p.3 / Chapter 1.4 --- Review on OSNR monitoring --- p.6 / Chapter 1.4.1 --- Polarization approach --- p.6 / Chapter 1.4.1.1 --- Polarization extinction --- p.6 / Chapter 1.4.1.2 --- Degree-of-polarization (DOP) analysis --- p.7 / Chapter 1.4.2 --- Interferometric approach --- p.7 / Chapter 1.4.3 --- RF spectral analysis approach --- p.8 / Chapter 1.5 --- Review on PMD monitoring --- p.8 / Chapter 1.5.1 --- DOP approach --- p.8 / Chapter 1.5.2 --- RF spectral analysis approach --- p.9 / Chapter 1.5.3 --- Arrival time measurement approach --- p.9 / Chapter 1.6 --- Objective of the thesis --- p.9 / Chapter 1.7 --- Linear expressions of optical impairments --- p.10 / Chapter Chapter 2 --- Monitoring of Linearly Accumulated Impairments in Unidirectional Links and Nodes --- p.12 / Chapter 2.1 --- Introduction --- p.12 / Chapter 2.2 --- Problem formulation --- p.12 / Chapter 2.3 --- Probing scheme --- p.19 / Chapter 2.3.1 --- Two-link-connected networks --- p.19 / Chapter 2.3.1.1 --- Ring network --- p.20 / Chapter 2.3.1.2 --- General two-link-connected network --- p.25 / Chapter 2.3.2 --- Tree networks --- p.28 / Chapter 2.3.3 --- Networks with bridges --- p.33 / Chapter 2.3.4 --- Illustrative example --- p.36 / Chapter 2.4 --- Single-fault localization --- p.42 / Chapter 2.5 --- Conclusion --- p.43 / Chapter Chapter 3 --- Monitoring of Linearly Accumulated Impairments in Directional Links --- p.45 / Chapter 3.1 --- Introduction --- p.45 / Chapter 3.2 --- Problem formulation --- p.45 / Chapter 3.3 --- Feasibility analysis --- p.48 / Chapter 3.4 --- Probing scheme --- p.50 / Chapter 3.4.1 --- Two-link-connected networks --- p.50 / Chapter 3.4.1.1 --- Probing scheme with only one monitoring module --- p.50 / Chapter 3.4.1.2 --- Optimal location --- p.51 / Chapter 3.4.2 --- Tree networks --- p.56 / Chapter 3.4.3 --- Networks with bridges --- p.57 / Chapter 3.4.4 --- Illustrative example --- p.58 / Chapter 3.5 --- Reliability and fault localization --- p.64 / Chapter 3.5.1 --- Fth-order probing scheme --- p.64 / Chapter 3.5.2 --- Locations of monitoring modules for Fth-order probing scheme --- p.67 / Chapter 3.5.3 --- Fault localization in Fth-ordcr probing scheme --- p.68 / Chapter 3.6 --- Conclusion --- p.69 / Chapter Chapter 4 --- Other Models --- p.70 / Chapter 4.1 --- Introduction --- p.70 / Chapter 4.2 --- Models --- p.70 / Chapter 4.3 --- Probing scheme for El --- p.71 / Chapter 4.4 --- "Necessary locations of monitoring modules for EN2, EN3 and EN4" --- p.72 / Chapter 4.5 --- Conclusion --- p.79 / Chapter Chapter 5 --- Summary and Future Works --- p.81 / Chapter 5.1 --- Summary of the thesis --- p.81 / Chapter 5.2 --- Future works --- p.83 / Bibliography --- p.84 / Appendix - List of publications --- p.88

Thesis (Ph. D.)--University of Hong Kong, 2010. / Includes bibliographical references (leaves 97-102). Also available in print.

Thesis (Ph. D.)--University of Massachusetts Amherst, 2009. / Includes bibliographical references (p. 200-223). Print copy also available.

M. Tech. Electrical Engineering / In recent years, there has been an increasing interest in real-time and delay sensitive applications. This is partly due to the increase in the use of video and audio streaming services. Most of these services depend on the User Datagram Protocol which is known as a fast and best effort protocol. However, there is no guarantee that packets sent via User Datagram Protocol will be received in their entirety. This is due to the absence of any packet error recovery mechanism in User Datagram Protocol. The purpose of this dissertation is therefore to investigate and evaluate the performance of raptor codes in packet based wireless networks.

Thesis(M.S.)--Auburn University, 2006. / Abstract. Includes bibliographic references (p.67-72).

Thesis, PlanB (M.S.)--University of Wisconsin--Stout, 2005. / Includes bibliographical references.