Investigating the Relations of Attacks, Methods and Objects in Regard to Information Security in Network TCP/IP Environment

Possibilities for investigations of 43 varieties of file formats (objects), joined in 10 groups; 89 information attacks, joined in 33 groups and 73 methods of compression, joined in 10 groups are described in the paper. Experimental, expert, possible and real relations between attacks’ groups, method’ groups and objects’ groups are determined by means of matrix transformations and the respective maximum and potential sets are defined. At the end assessments and conclusions for future investigation are proposed.

Types of Addresses and Levels of use in the TCP/IP Protocol Stack

The publication comments on certain moments of the method of teaching the types of addresses and their use in the TCP/IP protocol stack.

Pause intensity:a no-reference quality assessment metric for video streaming in TCP networks

In this paper a full analytic model for pause intensity (PI), a no-reference metric for video quality assessment, is presented. The model is built upon the video play out buffer behavior at the client side and also encompasses the characteristics of a TCP network. Video streaming via TCP produces impairments in play continuity, which are not typically reflected in current objective metrics such as PSNR and SSIM. Recently the buffer under run frequency/probability has been used to characterize the buffer behavior and as a measurement for performance optimization. But we show, using subjective testing, that under run frequency cannot reflect the viewers' quality of experience for TCP based streaming. We also demonstrate that PI is a comprehensive metric made up of a combination of phenomena observed in the play out buffer. The analytical model in this work is verified with simulations carried out on ns-2, showing that the two results are closely matched. The effectiveness of the PI metric has also been proved by subjective testing on a range of video clips, where PI values exhibit a good correlation with the viewers' opinion scores. © 2012 IEEE.

An objective approach to measuring video playback quality in lossy networks using TCP

In this work, we investigate a new objective measurement for assessing the video playback quality for services delivered in networks that use TCP as a transport layer protocol. We define the new metric as pause intensity to characterize the quality of playback in terms of its continuity since, in the case of TCP, data packets are protected from losses but not from delays. Using packet traces generated from real TCP connections in a lossy environment, we are able to simulate the playback of a video and monitor buffer behaviors in order to calculate pause intensity values. We also run subjective tests to verify the effectiveness of the metric introduced and show that the results of pause intensity and the subjective scores made over the same real video clips are closely correlated.

HYBRID TCP/UDP video transport for H.264/AVC content delivery in burst loss networks

In this paper we propose a hybrid TCP/UDP transport, specifically for H.264/AVC encoded video, as a compromise between the delay-prone TCP and the loss-prone UDP. When implementing the hybrid approach, we argue that the playback at the receiver often need not be 100% perfect, provided that a certain level of quality is assured. Reliable TCP is used to transmit and guarantee delivery of the most important packets. This allows use of additional features in the H.264/AVC standard which simultaneously provide an enhanced playback quality, in addition to a reduction in throughput. These benefits are demonstrated through experimental results using a test-bed to emulate the hybrid proposal. We compare the proposed system with other protection methods, such as FEC, and in one case show that for the same bandwidth overhead, FEC is unable to match the performance of the hybrid system in terms of playback quality. Furthermore, we measure the delay associated with our approach, and examine its potential for use as an alternative to the conventional methods of transporting video by either TCP or UDP alone. © 2011 IEEE.

How Green the Desert? Examining the Enviormental Policies of Las Vegas Strip Hotels

This study analyzed the websites of major Las Vegas Strip hotels, examined their corporate financial reports, and conducted two in-depth telephone interviews with hotel managers, all with regard to their “green” (pro-environmental) policies. The study found a distinct lack of evidence to support assertions that these properties had truly “gone green” in their daily operations. Thus, although the hotels might actually have been engaged in green procedures, they did not express environmental policy in their corporate websites or financial reports. Several possible reasons for this apparent duality are suggested.

Las Vegas night at Greek Orthodox Church in Brooklyn, NY

General note: Title provided by Freda Leinwand.

Effective video content distribution by combining TCP with adaptive FEC coding

This paper will look at the benefits and limitations of content distribution using Forward Error Correction (FEC) in conjunction with the Transmission Control Protocol (TCP). FEC can be used to reduce the number of retransmissions which would usually result from a lost packet. The requirement for TCP to deal with any losses is then greatly reduced. There are however side-effects to using FEC as a countermeasure to packet loss: an additional requirement for bandwidth. When applications such as real-time video conferencing are needed, delay must be kept to a minimum, and retransmissions are certainly not desirable. A balance, therefore, between additional bandwidth and delay due to retransmissions must be struck. Our results show that the throughput of data can be significantly improved when packet loss occurs using a combination of FEC and TCP, compared to relying solely on TCP for retransmissions. Furthermore, a case study applies the result to demonstrate the achievable improvements in the quality of streaming video perceived by end users.

An Evaluation of Tail Loss Recovery Mechanisms for TCP

Interactive applications do not require more bandwidth to go faster. Instead, they require less latency. Unfortunately, the current design of transport protocols such as TCP limits possible latency reductions. In this paper we evaluate and compare different loss recovery enhancements to fight tail loss latency. The two recently proposed mechanisms "RTO Restart" (RTOR) and "Tail Loss Probe" (TLP) as well as a new mechanism that applies the logic of RTOR to the TLP timer management (TLPR) are considered. The results show that the relative performance of RTOR and TLP when tail loss occurs is scenario dependent, but with TLP having potentially larger gains. The TLPR mechanism reaps the benefits of both approaches and in most scenarios it shows the best performance.

Los talleres de capacitation participativa (TCP) : una experiencia piloto

Los Talleres de Capacitación Participativa T.C.P., objeto de la acción investigativa descrita y sistematizada en la presente memoria, se plantean como una opción metodológica para la capacitación y el per-perfeccionamiento de docentes de Educación Superior en Colombia. Esta proposición se hace tanto a la luz del narco social, cultural y político de la educación en el país, como a partir del análisis de la realidad nacional y del panorama de transformación educativa que se vislumbra. El análisis de la relación de la teoría y la práctica-docente, permitió, igualmente, resaltar la importancia de la relación desarrollo y educación. De la misma manera, se pone en evidencia la formación del capital humano como recurso fundamental en una perspectiva que supere las visiones deterministas de la pedagogía tradicional, La presentación de una experiencia de aprendizaje en capacitación docente, cuyo análisis empírico se sistematizó en una propuesta de acción pedagógica, con las características fundamentales de la investigación protagónica, constituye el núcleo central de este trabajo. Los componentes metodológicos de la experiencia latinoamericana de los TED (Talleres de educación Democrática), el Programa PERFORHA (Perfeccionamiento y formación de maestros de la Universidad de Sherbrooke, Quebec-Canadá), los principios andrológicos y el método de sistematización de la práctica fundamentado en el constructivismo, constituyen los referentes pedagógicos que fundamentan los Talleres de Capacitación Participativa T.C.P., aplicados y sistematizados por los investigadores con los resultados que se observan en la presente memoria.

Diseño de una metodología que permita implementar el protocolo de internet versión 6 en empresas o instituciones con aplicaciones basadas en el protocolo TCP/IP versión 4

Se realizar una investigación para formar una base teórica que permita desarrollar un manual de referencia que sirva como consulta general sobre el uso del Protocolo de Internet versión 6, IPv6, y de las especificaciones básicas necesarias para migrar a esta nueva tecnología. Verificar el uso que hacen las empresas o instituciones en nuestro medio de aplicaciones operando en redes basadas en el Protocolo de Internet versión 4, con la idea de desarrollar pautas que sirvan para definir una metodología general para la migración de estas redes y sus aplicaciones en operación, al nuevo Protocolo de Internet IPv6

3D Porous Architecture of Stacks of β-TCP Granules Compared with That of Trabecular Bone: A microCT, Vector Analysis, and Compression Study

International audience