Overall Objectives
Scientific Foundations
Application Domains
New Results
Contracts and Grants with Industry
Other Grants and Activities
Inria / Raweb 2003
Project: ALCOVE

Project : alcove

Section: New Results

Collaborative Communication Platform

Stephane Louis-Dit-Picard did defend his PhD thesis in November 2003, on the specification of a distributed platform for 3D collaborative virtual environment  [11]. His proposition forms the core of our Spin|3D platform   5.1.

A serverless distributed architecture is proposed, each computer managing a copy of the shared objects. Data are exchanged between the computers in order to maintain the overall coherency of duplicated objects. A communication platform providing two coherency levels supports communication over an IP multicast network. The implementation is performed with a Corba middleware and multimedia real-time streams. Some distributed services are proposed to manage the virtual session.

A high level abstraction of the underneath communications channels is proposed. Applications' designers are able to easily create multi-user objects, using VRML97 along with some extensions. The sharing description of each object is embedded in the VRML97 source file.

An API called DAI, very close to the standard VRML97 EAI specification, is also proposed in order to create complex collaborative applications. The DAI, through a local Corba bus, enables external applications to connect to the Spin|3D platform, and manipulate objects contained within the Spin|3D browser.