Santiago Pavón

Universidad Politécnica de Madrid | UPM · Departamento de Ingeniería de Sistemas Telemáticos

Videos are extensively used nowadays to support learners in a variety of educational settings such as traditional online courses, MOOCs (Massive Open Online Courses), flipped classrooms, and blended courses. Therefore, it is of prime importance to develop methodologies capable of producing effective video-based learning courses which can lead to th...

This paper presents the concept and preliminary experiments of a system for assessing on the Quality of Service of multimedia flows. The goal is to devise a mechanism that allows a service provider to take action whenever poor quality of service is detected in the delivery of multimedia flows. Such procedure is fully automatic since it is based on...

This paper proposes the creation of an architectural layer for integration of all the resources and members participating in a given collaborative activity into a unified framework which is referred as the Collaborative Environment Integration Layer (CEIL). This layer is considered a necessary step for integrating with open standards all the collab...

Isabel is a P2P like multipoint group collaboration tool for the Internet, which implements an innovative service concept for synchronous collaborations based on a flexible and programmable floor control. This approach leads to a more natural and effective management of collaboration sessions. The flexible and programmable floor control incorporate...

IPv6 (Internet Protocol version 6) has been designed to resolve the requirements of the new Internet services. Although this is a network level protocol, applications are also affected by the IP version change. To complete the IPv6 transition, applications must be revised. The transition process can not be carried out instantaneously so, during the...

New Generation Internet will be based on new IP protocol version design to solve addressing problem and provide new functionalities. This paper describes guidelines to help the porting of applications to the new protocol IPv6, especially during the transition period. ISABEL collaborative application is used to exemp lify the porting methodology. IS...

Many multimedia applications have been developed during the past years for supporting co-operative work, tele-teaching and many other activities involving groups of persons distributed at different locations and communicating by means of telecommunication networks. Most of this effort has been devoted, till now, to deal with technical problems: net...

This paper describes the main issues arising during the port of the Isabel CSCW application to IPv6. Isabel has been ported to IPv6 in the European IST-1999-20393 LONG project. The port was validated in the distribution of the Madrid Global IPv6 Summit in March 2002. The distribution of the Global IPv6 Summit was a large trial where access to the c...

This paper describes the main issues arising during theport of the Isabel CSCW application to IPv6. Isabel hasbeen ported to IPv6 in the European IST-1999-20393LONG project. The port was validated in the distributionof the Madrid Global IPv6 Summit in March 2002. Thedistribution of the Global IPv6 Summit was a large trialwhere access to the confere...

ISABEL provides a platform for development of new multimedia services, including distributed conferences, with presentations and attendances located in rooms at different sites. ISABEL permits the definition of new services adapted to the specific requirements of each case. It builds its own communication network providing a uniform Quality of Serv...

This paper decribes the 1995 RACE Summer School ABC'95. ABC'95 has been a massive event where up to forteen auditoriums spread all over Europe have been interconnected during one week. The ISABEL CSCW application together with a videoconferencing network and a broadband ATM subnetwork established over the Pan European ATM Pilot network has provided...

rece un sistema para poder configurar y probar muy rapidamente escenarios muy variados asociados a un cierto tipo de conferencia distribuida de trabajo cooperativo. ISABEL ha sido desarrollada en los proyectos ISABEL e IBER 1 . El objetivo del proyecto ISABEL era la interconexion de las islas ATM RECIBA y RIA desarrolladas por Telefonica (Espana) y...

This paper aims to show the benefits and the experiences of ISABEL application ??. The aim of ISABEL is to assess the benefits of New Distributed Multimedia Applications using Integrated Broadband Communications (IBC) to support modern cooperative services. In contrast to single user computer applications, distributed collaborative systems consists...

This paper describes the use of ISABEL in an heterogeneous network context where different QoSs are used to connect different participants in a real-time interactive collaboration based on videoconferencing. As ISABEL uses TCP-UDP/IP to interconnect different network technologies and no QoS control exists, a QoS adaptation function has been added:...

The structure of the marketplace in which ATM will be introduced (as a widespread commercial public service) is still being clarified. The marketplace is being turned upside down by technological developments, of which ATM and Multimedia (MM) are parts, and by regulatory developments which are driven partly by technology changes and partly by marke...

This paper decribes experience of usage of the ISABEL application as well as the basic elements and functionality of the application. ISABEL is a configurable CSCW application which has been conceived with a toolbox approach such that it can be taylored to the requirements of different application domains with a small effort. ISABEL supports N to N...

Users are looking towards ATM technology as a suitable solution for specific applications in the new field of distributed multimedia. The aim of ISABEL is to take benefit of the new broadband technology in order to provide a good access to new distributed multimedia facilities. The application has been developed to cover two main fields: distance l...

The interleaved expansion presented in [QLP93] is a method to compute and represent the global events of a system preserving parallelism. As a side effect, this method provides important advantages in the technology of translation from LOTOS to Petri nets over static (direct) transformations and opens a simple process algebra form of representation...

Without Abstract

This chapter provides an application oriented description of the LOTOS Design Methodology produced in the Lotosphere project. This design methodology is a formally based stepwise refinement approach to system design, conceived to give formal support to an industrial design process, in order to achieve high quality designs.

Users are looking towards ATM technology as a suitable solutionfor specific applications in the new field of distributed multimedia. The aim ofISABEL is to take benefit of the new broadband technology in order to providea good access to new distributed multimedia facilities. The application has beendeveloped to cover two main fields: distance learn...

This paper presents an improved version of the interleaved expansion which generates a compressed representation of the transition system of a LOTOS behaviour expression in which interleaved actions are not expanded, but kept isolated. The compressed state space representation contains only the expansion of actions synchronizing and achieves a very...

This article presents two algorithms for transforming a monolithic LOTOS behaviour into two processes composed by the parallel operator. These algorithms are particular cases of the overall concept Inverse Expansion, which is based on the inversion of the so-called Expansion Theorem. The transformations presented in this article maintain the observ...

LOTOS is a Formal Description Technique developed within ISO to specify services and protocols. This paper describes a tool for doing LOTOS to LOTOS transformations. It has applications in state exploration, deadlock detection, testing, validation and in design by stepwise refinement. The transformations are: expansion (transformation of parallelis...

This paper proposed the use of RDF language for describing infor-mation related to the definition, deployment and operation of an advanced mul-timedia service. This service is provided through an overlay network which is also described using this formalism. Starting from a real problem we faced to-day we proposed the use of RDF in order to solve so...

Los sistemas de videoconferencia han utilizado tradicionalmente protocolos propietarios que los impedían interoperar. Sin embargo, en los últimos años se está imponiendo la tendencia a usar protocolos abiertos para solucionar este problema. Este artículo describe la arquitectura de una pasarela genérica para acceder desde los clientes más típicos a...

Las aplicaciones de trabajo colaborativo hacen uso se múltiples flujos de datos, viéndose dificultado su funcionamiento por la presencia de cortafuegos y equipos que traducen las direcciones de red. En este artículo se describe una solución a estos problemas consistente en la creación de una red superpuesta a través de la cual se encapsula todo el...