Telepathology is defined as the practice of pathology at a distance using video imaging and telecommunications. In this thesis we address the two main technology challenges in implementing telepathology, viz. compression and transmission of digital pathology images. One of the barriers to telepathology is the availability and the affordability of high bandwidth communication resources. High bandwidth links are required because of the large size of the uncompressed digital pathology images. For efficient utilization of available bandwidth, these images need to be compressed. However aggressive image compression may introduce objectionable artifacts and result in an inaccurate diagnosis. This discussion helps us to identify two main design challenges in implementing telepathology, 1. Compression: There is a need to develop or select an appropriate image compression algorithm and an image quality criterion to ensure maximum possible image compression, while ensuring that diagnostic accuracy is not compromised. 2. Transmission: There is a need to develop or select a smart image transmission scheme which can facilitate the transmission of the compressed image to the remote pathologist without violating the specified bandwidth and delay constraints. We addressed the image compression problem by conducting subjective tests to determine the maximum compression that can be tolerated before the pathology images lose their diagnostic value. We concluded that the diagnostically lossless compression ratio is at least around 5 to 10 times higher than the mathematically lossless compression ratio, which is only about 2:1. We also set up subjective tests to compare the performance of the JPEG and the JPEG 2000 compression algorithms which are commonly used for compression of medical images. We concluded that JPEG 2000 outperforms JPEG at lower bitrates (bits/pixel), but both the algorithms perform equally well at higher bitrates. We also addressed the issue of image transmission for telepathology by proposing a two-stage transmission scheme, where coarse image information compressed at diagnostically lossless level is sent to the clients at the first stage, and the Region of Interest is transmitted at mathematically lossless compression levels at the second stage, thereby reducing the total image transmission delay.

Ethernet está empezando a pasar de las redes de área local a una red de transporte. Sin embargo, como los requisitos de las redes de transporte son más exigentes, la tecnología necesita ser mejorada. Esquemas diseñados para mejorar Ethernet para que cumpla con las necesidades de transporte se pueden categorizar en dos clases. La primera clase mejora solo los componentes de control de Ethernet (Tecnologías basadas en STP), y la segunda clase mejora tanto componentes de control como de encaminamiento de Ethernet (tecnologías basadas en etiquetas). Esta tesis analiza y compara el uso de espacio en las etiquetas de las tecnologias basadas en ellas para garantizar su escalabilidad. La aplicabilidad de las técnicas existentes y los estudios que se pueden utilizar para superar o reducir los problemas de escalabilidad de la etiqueta son evaluados. Además, esta tesis propone un ILP para calcular el óptimo rendimiento de las technologias basadas en STP y las compara con las basadas en etiquetas para ser capaz de determinar, dada una específica situacion, que technologia utilizar. / Ethernet is starting to move from Local area networks to carrier networks. Nevertheless as the requirements of carrier networks are more demanding, the technology needs to be enhanced. Schemes designed for improving Ethernet to match carrier requirements can be categorized in two classes. The first class improves Ethernet control components only (STP based technologies), and the second class improves both Ethernet control and forwarding components (label based forwarding technologies). This thesis analyzes and compares label space usage for the label based forwarding technologies to ensure their scalability. The applicability of existing techniques and studies that can be used to overcome or reduce label scalability issues is evaluated. Additionally this thesis proposes an ILP to calculate optimal performance of STP based approaches and compares them with label based forwarding technologies to be able to determine, given a specific scenario, which approach to use.

Thesis (M.Eng.Sc.)--University of Adelaide, Dept. of Electrical and Electronic Engineering, 2001. / Bibliography: leaves 128-135.

Thesis (M.ICT.)--University of Wollongong, 2006. / Typescript. Includes bibliographical references: leaf 112-121.

Thesis (M.Sc. (Computer Science)) - Rhodes University, 2008

Thesis (M.S.)--University of Alabama at Birmingham, 2008. / Description based on contents viewed Oct. 7, 2008; title from PDF t.p. Includes bibliographical references (p. 80-81).

Bibliography: leaves 128-135. Investigates the behaviour of TCP bulk file transfer application sessions in a broadband access environment. Introduces some concepts for evaluating network behaviour: a path instability parameter for analyzing different TCP connections; a minimum RTT delay and a minimum typical path for estimating path characteristics between a client and application servers.

Thesis (MScEng)--University of Stellenbosch, 2003. / ENGLISH ABSTRACT: The aim of this thesis is to investigate the implementation of a high-speed serial bus based on the IEEE Std 1394-1995 specification for use in a microsatellite. Earth observation microsatellites carry imagers (or cameras) that take photographs of the earth. Each photograph generates a large volume of digital data that has to be transferred to either a storage device, a RF transmission unit or a video processing device. Traditionally, the connection between such systems were dedicated serial bus systems that were custom designed for just that purpose. This thesis will investigate the the implementation of a generic alternative to such a custom serial bus. The IEEE 1394 serial bus will allow many devices and subsystems to be connected to the serial bus and will allow these different subsystems to exchange data between each other. As an example implementation, a real-time video link between two points using the IEEE 1394 serial bus will be developed. / AFRIKAANSE OPSOMMING: Die doel van hierdie tesis is om ondersoek in te stel na die bou van 'n hoëspoed seriebus vir gebruik in 'n mikrosatelliet gebaseer is op die IEEE Std 1394-1995 spesifikasie. Aardobservasie-mikrosatelliete bevat kameras wat fotos van die aarde neem. Elke foto genereer groot volumes digitale data wat na óf 'n massastoor, óf 'n RF-sender, óf 'n video-verwerkingseenheid gestuur word. Tradisioneel is elkeen van hierdie verbindings met 'n toegewyde seriebus gedoen wat spesiaal vir daardie doel gemaak is. Hierdie tesis het dit ten doelom ondersoek in te stel na 'n generiese alternatief vir hierdie toegewyde seriële busse. Die IEEE 1394 seriebus sal toelaat dat verskeie eenhede en substelsels aan mekaar gekoppel kan word en dat hulle data tussen mekaar kan uitruil. Ter demonstrasie sal 'n intydse videoskakel ontwerp word wat die IEEE 1394 seriebus gebruik om data tussen twee punte oor te dra.

The Session Initiation Protocol (SIP) has in recent years become a popular protocol for the exchange of text, voice and video over IP networks. This thesis proposes the use of a class of structured peer to peer protocols - commonly known as Distributed Hash Tables (DHTs) - to provide a SIP overlay with services such as end-point location management and message relay, in the absence of traditional, centralised resources such as SIP proxies and registrars. A peer-to-peer layer named OverCord, which allows the interaction with any specific DHT protocol via the use of appropriate plug-ins, was designed, implemented and tested. This layer was then incorporated into a SIP user agent distributed by NIST (National Institute of Standards and Technology, USA). The modified user agent is capable of reliably establishing text, audio and video communication with similarly modified agents (peers) as well as conventional, centralized SIP overlays.

The transmission of realtime audio data across digital networks is subject to strict quality of service requirements. These networks need to be able to guarantee network resources (e.g., bandwidth), ensure timely and deterministic data delivery, and provide time synchronisation mechanisms to ensure successful transmission of this data. Two open standards-based networking technologies, namely IEEE 1394 and the recently standardised Ethernet AVB, provide distinct methods for achieving these goals. Audio devices that are compatible with IEEE 1394 networks exist, and audio devices that are compatible with Ethernet AVB networks are starting to come onto the market. There is a need for mechanisms to provide compatibility between the audio devices that reside on these disparate networks such that existing IEEE 1394 audio devices are able to communicate with Ethernet AVB audio devices, and vice versa. The audio devices that reside on these networks may be remotely controlled by a diverse set of incompatible command and control protocols. It is desirable to have a common network-neutral method of control over the various parameters of the devices that reside on these networks. As part of this study, two Ethernet AVB systems were developed. One system acts as an Ethernet AVB audio endpoint device and another system acts as an audio gateway between IEEE 1394 and Ethernet AVB networks. These systems, along with existing IEEE 1394 audio devices, were used to demonstrate the ability to transfer audio data between the networking technologies. Each of the devices is remotely controllable via a network neutral command and control protocol, XFN. The IEEE 1394 and Ethernet AVB devices are used to demonstrate the use of the XFN protocol to allow for network neutral connection management to take place between IEEE 1394 and Ethernet AVB networks. User control over these diverse devices is achieved via the use of a graphical patchbay application, which aims to provide a consistent user interface to a diverse range of devices.