Laboratorio para el estudio experimental del comportamiento de una red Ethernet

Este documento describe el laboratorio utilizado en las asignaturas de Arquitectura de Redes I y II y Comunicaciones I y II de cuarto de Ingeniería Informática y segundo de Ingeniería Técnica de Gestión para caracterizar el comportamiento de un red ethernet

Using laboratory to improve understanding of 802.3 physical characteristics

When teaching computer networks as part of a Computer Engineering degree, emphasis is placed on higher-layer protocols while Physical and Data-Link layers usually play a secondary role. Physical aspects of data communication are sometimes taught as an independent, not-related, topic whereas Data-Link concepts are “hard” to our students. We propose a new lab experience in which students can see IEEE 802.3 frames in a new way; by using standard digital oscilloscope we are able to go deeper into lower-level layers. The lab session will be divided into two parts, focusing on topics that are usually considered “hard” by our students. The first part will focus on physical aspects of a frame transmission whereas the second will focus on MAC-layer. For example, topics like physical layer synchronization, signal attenuation, 5-4-3 rule and even Interframe Gap are exercised at the lab session. This experience has been tested with a group of last year students; we have analyzed students "own perception" of previous knowledge of some related topics, the results from a evaluation questionnaire (a small exam given out to students) and students evaluation of this exercise.Ministerio de Educación y Ciencia TEC2006-0843

Analysis of the Behavior of an Indoor Position System Based on Fingerprints and IEEE 802.15.4

This paper presents an analysis of the behaviour of an indoor position system based on fingerprints and IEEE 802.15.4 that has been adapted to be tested in a competition, called EvAAL (Evaluating AAL Systems through Competitive Benchmarking), hold both in Madrid (tests) and Eindhoven (results). The objectives of this analysis are to determine the best algorithm that should have been applied in order to obtain the best results in the competition to use them in other environments. Among the different combinations that can be applied, i.e., the way the signature database is filled in and the algorithm uses to determine the closest location point, the best results are obtained using a global signature database where each signature entry is calculated by the medium of samples signatures database and the closest location is determined by a centroid algorithm with the parameter c set to 1.3. In this way, the error made improves the one obtained in the EvAAL, which is reduced by 100 centimetres.Junta de Andalucía p08-TIC-363

ESTELLE: A Method to Analyze Automatically the Performance of Telecontrol Protocols in SCADA Systems

This paper presents the use of ESTELLE, a formal description technique, as a method to calculate automatically the performance of telecontrol protocols in SCADAsystems. Some specific primitives are added to the ESTELLE description language in order to achieve that goal. As an example, we analyze the performance of a telecontrol protocol. The results from this method are compared to performance measurements obtained from analytical and simulated solutionsMinisterio de Ciencia y Tecnología TIC 2000-111

In Vitro Toxicity of Asparagus Saponins in Distinct Multidrug-Resistant Colon Cancer Cells

Colorectal cancer is the third most common cancer in the world. Many efforts have focused on finding natural molecules with potential chemo-preventive activity due to their low toxicity compared to synthetic drugs. However, comprehensive information on the bioactive fractions and components is still missing. In this study, we developed a method for the quantitative separation and isolation of saponins from asparagus genotypes consisting of an adsorption chromatography and subsequent liquid chromatographic separation on a reversed-phase column. The saponins isolated were tested for their cytotoxic activity against human colon cancer cell lines, which could develop cross-resistance to a wide variety of chemotherapeutic drugs. Our results showed that Huétor-Tájar asparagus saponins (HTSAP), mainly protodioscin and HTSAP-10 have higher cytotoxic activity than HTSAP-1, HTSAP-6, and HTSAP-8. This study links the potential anticancer effect of asparagus to specific saponins and unveils the triguero Huétor-Tájar asparagus as a nutraceutical particularly in colon cancer therapiesMinisterio de Economía y Competitividad JCI-2012-1308

Integration of expert system rules into standarized object description models for telecommunication network management

The work described in this paper is focused on the attainment of a product that: a) is able to manage a communication network according to ISO ant ITU-T standards (Telecommunication Management Network, TMN, model); b) automatically locates network faults based on a set of rules embedded in an integrated expert system; and c) represents the expert knowledge using procedures and tools to define object and object classes, following the internationally standardized model. The most outstanding characteristic of the product is the availability of expert functionalities integrated into the very object definition of the management system

Choosing the Right Protocol Stack for an Open and Flexible Remote Unit

This paper presents some works made in the development of communications software for an embedded open core system. By using a Linux-based processor implemented on a FPGA, we are developing the appropriate software in order to implement a remote unit to be used in a telecontrol network. We present an analysis of the physical devices needed and a performance report of them. After that, we analyze the requirements of the telecontrol network and the possibility of reusing already implemented protocols in Linux instead of using standard telecontrol protocols.Junta de Andalucía EXC-2005-TIC-1023Ministerio de Educación y Ciencia TEC2006-0843

IEC-60870-5 application layer for an Open and Flexible Remote Unit

This paper presents the development and test of the standard IEC-60870-5 application layer protocol for a Remote Terminal Unit (RTU) based on open hardware and software. The RTU hardware is an embedded system, a SoC-type design using FPGA that has been programmed with the open core LEO. with Linux operating system running over it, so both the hardware and IOS are open source. For prototyping the GR-XC3S-1500 board has been used. There is no open source code available for the IEC standard protocols, so application layer protocol has to be implemented. All the software design has been made in a PC platform using standard development tools. The source code generated for the protocol has been compiled with the standard Linux gcc compiler in LEO.. Several tests have been made to prove the right behavior of the protocol as well as its performance over different transmission mediums.Junta de Andalucía EXC-2005-TIC-1023Ministerio de Educación y Ciencia TEC2006-0843

Implementing IEC 60870-5 data link layer for an Open and Flexible Remote Unit

This paper presents an open source implementation for a data-link layer protocol specified in IEC 60870, protocol specification for telecontrol networks. It has been tested over LEON an embedded system with a Linux based operating system. Protocol engineering methods have been used in order to implement the protocol. The standard is in natural language so a formal language is needed to describe its behavior. A prototype has also been created to simulate the protocol behavior. The protocol has been tested on a real environment, using PCs and LEON as primary and secondary stations, and different physical layers, serial cable, radio frequency and GSM.Junta de Andalucía EXC-2005-TIC-1023Ministerio de Educación y Ciencia TEC2006-0843

Efectividad de 5-fluoruracilo y vinorelbina en pacientes multitratadas por cáncer de mama metastásico

Objetivo. Evaluar la actividad y toxicidad de fluoruracilo en infusión continua y vinorelbina en segunda o tercera línea de tratamiento del cáncer de mama metastásico (CMM). Método y pacientes. En este estudio fase II se incluyeron 24 pacientes que habían recibido doxorrubicina y/o paclitaxel. Se administró 5-fluoruracilo a 1g/m2/día en infusión continua por 3 días y vinorelbina a 30 mg/m2 D1 cada 21 días por 6 ciclos. Resultados. Las respuestas globales observadas fueron del 37,5% (12,5% respuestas completas). El período libre de enfermedad se calculó una media de 6,33 ± 8,12 meses (IC 95% de 3,43 meses). Se observó toxicidad en el 12,5% de las pacientes y no se registró toxicidad grave ni muertes relacionadas a tratamiento. Conclusión. El 5-fluoruracilo/vinorelbina a las dosis administradas es un esquema efectivo en pacientes con CMM multitratadas, con un bajo perfil de toxicidad y costo