Transcript ICETA 2003 2

RESEARCH
Global Platform for Rich Media
Conferencing and Collaboration
G. Denis, Caltech
Why to use this technology ?
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Collaboration tools and technologies provide a
very efficient way to work for spread group of
scientists.
They improve the feeling of presence and to be a
part of a team.
They avoid the wasted time and money on travels
and hotels.
They allow larger collaborations.
The frontiers and the distances are not barriers
anymore.
The lastest technologies give more than a remote
meeting possibility but ways to share and
contribute in documents, applications and
developments.
Existing Technologies
1.
Through Numerical Telephone Line (Obsolete)
ISDN or CODEC (H.320)
Good: secure, good hardware, no packet lost
Bad: expensive, limited bandwidth, not flexible
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Through IP Network
Good: flexible, cheap, extensible, no bandwidth
limitation, choice of standard and protocol
Bad: no echo-cancellation always available, no
QoS, not so secure
1. Mbone
2. H.323
3. SIP
4. Others
Mbone Tools
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These applications have been developed more 10
years ago to use the Multicast Backbone. The
audio and video are split in 2 different applications.
VIC is the video application that can decode and
encode several different codecs. It is very flexible
and provide controls to set the frame rate, the
compression and bandwidth of the video sent. It
can display dozens of videos at the same time.
VAT and RAT are the audio applications. There’s no
software echo cancellation built-in but they can
code and decode a very large number of codecs.
These applications are using RTP/RTCP protocol
through unicast or multicast connection.
Were the first videoconf. clients used in VRVS.
H.323 ITU Standard
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The ITU designed this standard for IP
conferencing.
It is based on the H.320 philosophy, adapted for IP
networks.
The best hardware clients available today
implement and use this standard.
It is technology adopted in the professional
market.
Every component is expensive.
The H.323 multi-point solution (MCU) is complex,
very expensive and limited in term of number of
participants and scalability. It requires at least 1
MCU and 1 gatekeeper (kind of LDAP).
The next version of the clients soon will not be
limited to 768kbs.
Session Initiation Protocol
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SIP is a signaling protocol for Internet
conferencing, telephony, presence and instant
messaging.
Developed within the IETF MMUSIC (Multiparty
Multimedia Session Control) working group , with
work proceeding since September 1999 in the IETF
SIP working group.
It is more recent than H.323 and has a better
design to fit the IP networks needs, capabilities
and constraints. No limitation and very open.
Already adopted by Microsoft (Messenger), Apple
(iChat AV) and other open source projects.
Will be supported by VRVS very soon (already
working in prototype version).
VRVS Description
VRVS : a Videoconf. Service
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The Virtual Rooms Videoconferencing System
have been developed by Caltech since 1995 to
provide a world wide videoconference service
for education and research communities.
A web based interface provides an easy to use
graphical user interface to organize and
participate to meetings.
No limitation on participants number.
Different technologies and protocols are
supported (and mixed) and allow users to
connect their preferred videoconferencing tool.
Supports Mbone, H.323, SIP, QuickTime, Access
Grid, JMF and MPEG2.
It is composed of 1 main server and several
reflectors (network servers) spread around the
world.
Web based interface
 VRVS provides a natural and
intuitive interface to organize
and manage your meetings.
 Several interfaces let you see
in 1 shot all current
conferences, let you book a new
one in 3 clicks.
 Several academic
communities are handled by
VRVS. Each one has its specific
Virtual Rooms.
 VRVS manages multi
international time zones in a
transparent way.
 Its use does not require
technical knowledge nor
technician action.
Connection Interface
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Connect / Disconnect the selected videoconference client
Provide different video modes
Allow CHAT and Private messages
Can share your computer desktop
Remote control of video cameras.
 co-browsing of web sites
 real time list of connected participants
 share computer desktop with other participants
Example 1: 20 participants
BRAZIL (3 sites) + SWITZERLAND (CERN) + USA (Caltech)
Exemple 2: 17 participants
JAPAN + UK + SWITZERLAND + BRAZIL + USA (SLAC + FERMILAB)
Network and Security
The reflectors are inter-connected according the best
networking path.
 Optimized network bandwidth utilization
 Possibility of tunneling (TCP or UDP) between
reflector servers. All communications use only ONE
port !
 are designed in Peer-to-peer with high scalability and
flexibility
 Solution for Firewall and NAT
 Perform some packet recovery
 Dynamically adjust bandwidth for H.323 multipoint
conference between End Points to an overall maximum
conference bandwidth
 Real-time packet loss monitoring
 Support up to 16,000 Virtual Rooms (parallel
meetings)
VRVS Model Implementation
VRVS Web User Interface
(vic, vat/rat,..)
SIP
H.323
QuickTime
Player
MPEG
Minerva
QoS
VRVS Reflectors (Unicast/Multicast)
Collaborative
Applications
Mbone
Tools
Real Time Protocol (RTP/RTCP)
Network Layer (TCP/IP)
done
Partially done
Work in progress
Continuously in development
Extra Features
Virtual Access Grid
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User can connect to either unicast or multicast
videoconferencing with full supported features
 User can create his/her own virtual AG node and
virtual venues integrated into VRVS
 Different Video modes possible:
Voice switched: default mode for H.323 clients.
one video stream at a time
Timer switched: browse through all the video
based on preset timer. One video stream at a
time.
Selected Streams: Click among the video
participants to view selected video streams (one
or several streams available).
All Streams
VAG with Mbone Clients
Administration Interface
o Pure Java J2EE + XML
o HTTPS/SSL secure web interface
o Monitoring reflectors and users in ongoing conference
o Full control on database
Real-Time Monitoring
VRVS Virtual Setup
1 dual processors PC
With special 4 output graphic card
6400 x 4800 pixels
Most powerful VRVS End Node
What next ?
Future Features (1/2)
 Adaptation to emerging standards: IPv6, SIP
 Develop advanced monitoring and tracking tools
for ad-hoc conference as well as scheduled multisite conferences
 Improve Security
Transparent solution for NAT
Conference access control, user authorization
 Develop a pure peer-to-peer VRVS reflectors
network to be able to handle thousands of parallel
sessions.
Future Features (2/2)
 Wireless/Mobile Client Integration:
 User Interface dedicated for small screens
 Integration of low end client:
Provide dedicated software clients (VVP, JMF)
Transcode streams to lower bandwidth
Support MPEG4
 Integration of new hardware/software for high-end
interactivity.
 Already developed an MPEG2 MCU (using Minerva codec). Will
port to other codec if demand.
Provide dedicated software clients (VVP, JMF)
Developed a multipoint videoconferencing system based on MPEG4
compression standard.
Developed a system using HDTV standard If affordable hardware
devices available.
VRVS Usage
VRVS : A production service since 1997
Number of Registered Users:
5200 users m 86 Countries
USA
1210
Spain
884
Italy
376
Switzerland
330
Brazil
258
France
248
Germany
247
UK
205
Japan
108
Canada
89
61 users in Slovakia
VRVS Reflectors Deployment
Machines and OS
Machines used in VRVS
VRVS support different
Operating Systems
according to the need
and the demand of the
final users:
923
136
1733
Connections from Machines
1st
: Windows
2nd: Linux
3rd: Macintosh
4th: Other UNIX
Windows
Linux
Macintosh
Others
11805
2045
11856
Windows
Linux
Macintosh
Others
30021
143760
VRVS, Caltech Team
Philippe Galvez
Project Leader
Pasadena (USA)
Gregory Denis
Main Developer
Geneva (Switzerland)
David Collados
Administration Developer
Geneva (Switzerland)
Kun Wei
Reflector Developer
Pasadena (USA)
Dave Adamczyk
CGI, Java and SIP Developer
Pasadena (USA)
Joao Correia
Support Responsable
Geneva (Switzerland)
Pavel Farkas
H.261 & H.263 codecs
Kosice (Slovakia)
Juraj Sucik
Mbone dev. + reflectors
deployment
Kosice (Slovakia)
Michal Pauliny
Mbone dev.
Kosice (Slovakia)
WWW.VRVS.ORG
[email protected]
[email protected]
Supported Operating Systems
1. Windows
2. Linux
3. Mac OS X
4. Other Unix (Solaris, IRIX…)