A Platform for Distribution Virtual Environment

1. A Platform for Distribution Virtual Environment RENATA CRUZ TEIXEIRA OTTO CARLOS M.B. DUARTE

2. Introduction • The aim of virtual distributed environments. • The main limitations of distributed virtual reality system. • Some samples of virtual distributed environments.SimNet Systems, EpsNET-IV, WOW

3. The Proposed Platform • Platform Design. • Platform Architecture. • Service and protocol description

4. Platform Design • Two goals: Scalability, Flexibility • Ensure consistency control in each group by a special host called leader. • Divide the participants into multicast groups • Adopt a distributed data model, partitioning virtual world data among its users.

5. Platform Design(continue) • Uses three communications with different features. • IP Multicast • SRM • TCP

6. Platform Architecture

7. Service and Protocol Description • The service primitives • VR_Con.Req • VR_Con.Ind • VR_Con.Conf • VR_Dis.Req • VR_Dis.Ind • VR_Update.Req • VR_Update.Ind

8. Service and Protocol Description(con1.) • PDU’s • JR, JI, JC, LR, FNL, ES • The Predicate_Action Petri Net model • On sample of the model(enter the virtual world)

9. Service and Protocol Description(con1)

10. Service and Protocol Description(con2)

11. Sample(Entering the virtual world)

12. Simulation • Simulation Infrastructure • Simulation Model • Measurements Performed

13. Topology Generation

14. Simulation Model • Parameters of Simulation Model • DB initial size, Avatar size, Update size, Pm • Detail of Simulation Model • The virtual environment is divided into fixed areas. • The environment is divided among all leaders • The leaders. • Participant’s movement

15. Measurements Performed • Delay • Transmission of a join request(JR PDU) to the leaders by SRM • Waiting time due to leader reaction to the request. • Establishment of a TCP connection. • Transmission of the database by the TCP. • Others • The number of messages exchanged • The number of handoffs

16. Platform Performance • Partition of Virtual Environment • Figure 1 --- Delay to enter the virtual environment and to perform a handoff • Figure 2 --- Total number of handoffs for all participants • Figure 3 --- Number of messages exchanged for the topology with 32 participants Participant’s speed

17. Delay to enter the virtual environment and perform a handoff

18. Total number of handoffs for all participants

19. Number of Messages exchange with 32 participants.

20. End