Introduction:The Web over ATM (WoA) project of the Section de Systèmes de Communication (SSC), deals with various aspects of the Web, of ATM networks and their interoperation. These include coding of MPEG2 streams for transport over ATM, creating switched ATM connections to transfer Video, Virtual Reality, protocol validation and prototyping as well as automatic host configuration for web-based services. This is the second and final demo of the project. This year, the ACTS EXPERT project (WP2) will also be participating in the demo, to the extent of setting up switched renegotiable ATM connections to Basel. The project 'Selective QUality guaranTee for distRibuted corporAte networks' (SUTRAS) is a collaborative CTI project between Datelec and EPFL-LRC.
Programme for the demo:The programme for the demo is the following: 3:00 - 3:15pm General presentation of the project and research activities Prof. J.Y. Le Boudec 3.15 - 3:40pm "Virtual Humanoids" Christian Babski 3.40 - 4:00pm "Real-time remote access and browsing of medical images through Web and ATM" Constant Gbaguidi, Raffaele Noro, Olivier Verscheure 4.00 - 4:20pm "WoA-EXPERT Demo: Arequipa for VIdeo Conferencing (VIC)" Werner Almesber, Leena Chandran-Wadia Silvia Giordano, Rolf Schmid (EXPERT) 4.20 - 4:35pm "Hosts Synchronisation Using Multicast IP" Eric Gauthier, Ljubica Blazevic 4.35 - 4:50pm "CTI Project Demo: SUTRAS" Hans Einsiedler 4.50 - 5:10pm "CORBA over ATM" Antonio Restrepo 5.10 - 5:30pm "Perceptual Syntactic Information Coding of MPEG streams" Olivier Verscheure 5:30pm - Apero - hosted by ASCOM Tech. Ltd.
Short descriptions of the presentations:A short description of the contents of each demo is given below, with links to more detailed versions of the demo scenarios. Publications relating to these demos will be compiled into a final report of the project, to appear in December 97.
Virtual Humanoidsby Christian Babski The demo will talk about "virtual humanoids invasion" more than only "humanoids in VRML" and will be in two parts : 1 - VRML: First way to export our bodies : adapt them to a specific standard. - introduction on VRML and the humanoids working group which define a standard way to represent a humanoid in VRML (specific hierarchy, animation). Presentation of our model. - Demo. of several animated humanoids inside a 3D model of EPFL (with may be an interface to guide user, and a modelisation of a lab (corridors, doors) with a specific room in which something usefull can be done... - I'm about to define/organise this with our designers). 2 - External Application : Export our bodies as they are defined inside commercial application. - Presentation of an example with DIVE (http://www.sics.se/dive/) a multi-user application. Explanation of the technics we are using to animate our bodies inside DIVE by using shared memory. - Demo : could be a stand alone body (the user) walking and playing animation, picking objects or a crowd simulation in a museum (autonomous actors (12) moving around.
Real-time remote access and browsing of medical images through Web and ATMby Constant Gbaguidi, Raffaele Noro and Olivier Verscheure The demo is about remote access to medical images so as to enable a remote expert to perform diagnosis about some disease (on the basis of the retrieved images). The demo layout involves a medical image server and one or many expert sites. The server is connected to these sites through a data network, specifically an ATM network. At the server side, images are grabbed from a camera connected to a microscope; then, they are digitalized and compressed in MPEG-2 format. The compression is done according to the perceptual quality demanded by the doctors. Important work has been carried out for taking into account human perceptual features - psychophysics - during the image encoding process. This results in better efficiency, since the quantity of information is optimized with respect to the information that is useful to and noticeable by the end-user. The psychophysics-aware compressed information is then held in storage, and eventually transmitted to the remote expert via the web and over ATM. Important is the fact that the expert may not have the appropriate software to handle the image retrieval and rendering process. An application localization and fetching scheme is proposed and implemented to give him some assistance. Unlike the legacy search schemes - such as WAIS, Harvest, Archie, etc. - the one we proposed accounts for the host specific architecture - operating system, available devices, etc. - in the search process. Hence, better search is performed which completely matches the user's demands. The search engine automatically locates the adequate software and launches it (automatic host configuration for web-based services). The expert is then able to make his diagnosis. For the specific application addressed by this demo, it is not too important to assure some quality of service at the receiver side. However, for more sophisticated applications like video-on-demand for which quality of service is crucial, a more elaborate QoS framework is needed, in order to launch the fetched software with the QoS requested by the end-user, namely the expert. A draft of this framework is under implementation.
WoA-EXPERT Demo: AREQUIPA for VIdeo Conferencing (VIC)by Werner Almesberger, Leena Chandran-Wadia Silvia Giordano and Rolf Schmid ASCOM Tech Ltd ATM on Linux is a comprehensive implementation of ATM-related protocols, including the latest signaling as specified in ATM Forum UNI 4.0. This platform is also used for the reference implementation of Arequipa (see below) and for experiments with renegotiation (modification of connection parameters while the connection is active, e.g. to accomodate for a change in an application's traffic profile) as specified in ITU-T Q.2963.1. EXPERT is an ACTS project active, among other areas, in ATM advanced signaling. EXPERTs' contribution to the demo is an experiment with switched and renegotiable ATM connections. The demo scenario is composed of PCs equipped with ATM on Linux implementation and Arequipa capable applications (WEB, VIC) and the ATMLightRing 1.25 System from ASCOM. The switch also implements ATM Forum UNI 4.0 signaling plus ITU-T renegotiation capability (Q.2963.1). In order to showcase the implementation of UNI 4.0 signalling and of Arequipa, the popular Mbone video tool VIC (VIdeo Conferencing) has been modified to use Arequipa. At the demo, VIC will run over the ATM WAN, transferrring live video to Zurich and Basel over switched, renegotiable ATM connections.
Hosts Synchronisation Using Multicast IPby Eric Gauthier and Ljubica Blazevic We have implemented a protocol to control access to multicast IP, the protocol distributes a right to send among the group members in a fair manner, to achieve this the protocol builds and maintains a spanning tree of the group members, the protocol is scalable: the state information kept by each host is independent of the group size and of the tree structure, the protocol is robust to packet loss, reordering and duplication. This protocol can be seen as a distributed mutual exclusion protocol that uses multicast IP.
CTI project Demo: SUTRASby Hans Einsiedler The immense growth of network demand, subsequent overload of the network and the rise of new applications requiring Quality of Service, makes further network control and increase in network resources necessary. Charging is a possible control mechanism not solely needed for purely economic reasons, and could aid preservation and enhancement of the current network infrastructure. We will demonstrate the possibility to choose Quality of Service within a network using a standard Web browser; in our case Netscape. The Quality of Service links will be ATM. The amount of traffic and the setup time will be computed and the user will receive this usage information after the connection has been closed.
CORBA over ATMby Antonio Restrepo In the LTI we have developed an ORB that allows asynchronous and synchronous operations with immediate or deferred invocation and that interoperates with other commercial ORBs. For the demo, we want to show how to do A/V streams in our CORBA environment using a high speed network. We will show an application developed using sC++ running over our ORB adapted to the ATM network of the LRC. This application will allow the flow of a video stream between two remote objects: one of them will act as source of MPEG frames (with a camera control), and the other will display the images in the screen. We think that the streams implementation is an important aspect that must be considered because the current trends in the telecommunication, multi-media and on-line markets suggest that the remote exchange of continuos audio/video media will also need support in the CORBA specifications.
Perceptual Syntactic Information Coding of MPEG streamsby Olivier Verscheure This work addresses the optimization of TV-resolution MPEG-2 video streams to be transmitted over packet networks facing a given packet loss probability. The main contribution of this work resides in the design of a new flexible scene-complexity adaptive mechanism, namely the Perceptual Syntactic Information Coding (PSIC) mechanism. The PSIC adaptively modulates the number of macroblocks per slice in order to optimize the global video quality which depends on both the video encoding quality and the video degradations due to data loss during the transmission. We compare its performance against a fixed-length slice scheme to be transmitted over ATM networks using AAL-5. Results show that the proposed mechanism behaves much better in terms of global perceptual video quality.
Last modified: Mon Oct 20 09:37:35 MET DST 1997 by Leena Chandran-Wadia