Wireless Access in Vehicular Environment (WAVE) Using BitTorrent and Bargaining

1. Wireless Access in Vehicular Environment (WAVE) Using BitTorrent and Bargaining Presented by Barsha Shrestha September 26, 2008 Thesis Defense

2. Outline • Background • BitTorrent • Vehicular Communications and WAVE • Game Theory and Bargaining • Proposed Scheme • Problem Formulation • Proposed Solution • Simulation Results • Conclusions and Future Works • References Thesis Defense

3. Querying Tracker File Download File Upload and Download BitTorrent Tracker Seed 68% 100% Swarm computers File download 45% 35% Leech File upload and download • Peer-to-Peer (P2P) file sharing protocol - used for transferring or downloading files Thesis Defense

4. OBU Vehicular Communication • Emerging technology which provides safety and efficiency in transportation systems • Download large files in wireless communication, • Motivation for BitTorrent Range of RSU OBU : On-Board Unit RSU : Road-side Unit Road-Side Unit (RSU) (e.g.: Toll Booth) V2V : Vehicle-to-Vehicle communication V2R : Vehicle-to-Roadside communication V2R V2R V2V Two-way Lane V2V All vehicles have OBU Thesis Defense

5. Provides architecture for Vehicular Networks WAVE + DSRC Vehicular Communication (contd..) • Developed under Intelligence Transportation System (ITS) • Implements internet so that there is wireless connection among vehicles and also other support systems to facilitate exchange of information • Federal Communication Commission (FCC) allocated 75 MHz of DSRC spectrum at 5.9 GHz for V2V and V2R communication • DSRC was moved to IEEE 802.11 group • WAVE: Wireless Access in Vehicular Environments • DSRC : Dedicated Short Range Communication Thesis Defense

6. Wireless Access Vehicular Environment • A hot topic which is still in the process of development • A communication standard which will be used in vehicular communication • Uses frequency of 5.8 /5.9 GHz with a guard band from 5.850-5.855 GHz • A part of a group of standards of protocols for DSRC • DSRC provides high rate of data transfer with low delay • Main objective of WAVE • Provide connections with the applications in the vehicle and between the wireless devices in quickly changing environment • Exchange of information must be completed in very short time Thesis Defense

7. WAVE consists of following components: • IEEE 802.11p • IEEE P1609 • IEEE 802.11p • IEEE 802.11 is set of standards defined for wireless local area network (WLAN) • New standards for Vehicle-to-Vehicle communication and Vehicle-to-infrastructure communication known as IEEE802.11p • Main technology of WAVE and is used for PHY/MAC • It will allow data exchange within 100 milliseconds for vehicles in high speed Thesis Defense

8. IEEE P1609 • Describes the security, management, physical access in WAVE communication • Takes care of operation of DSRC channels • IEEE P1609.3 (networking services) covers WAVE connection setup and management • IEEE 1609.4 (Multichannel operations) enables operation of upper layers across multiple channels Thesis Defense

9. Safety and Non-safety Applications WSMP ( WAVE Short Message Protocol ) IEEE P1609.3 UDP IpV6 Link WAVE WAVE MAC IEEE P1609.4, 802.11p WAVE PHY IEEE 802.11p • DSRC Standards and Communication stack Thesis Defense

10. Game Theory • Bit-torrent in P2P network developed in wired network which is controlled in a centralized way • Vehicular environment needs distributed solution. • Motivation for Game Theory, which is a branch of applied mathematics and economics where players bargain using strategies producing outcomes depending on their utilities or preferences. • Game : Interaction between two people where decision of one affects the outcome of other • Players : People involved in Game • Strategy : Action a player takes to get maximum benefit • Utility: Satisfaction that a consumer attains from consumption of any economically beneficial good or service Thesis Defense

11. Game Theory (contd..) • A game can be co-operative and non-cooperative. • Non-Cooperative games • Games where the players do not co-operate and they are focused to achieve their own goals • Players do not communicate • Example : Football game • Cooperative games • Games in which players cooperate with each other by following some set of defined rules • Players communicate with each other • Mutual benefit • Example : Bargaining Thesis Defense

12. Bargaining • Negotiation of goods or services carried out between two or more players • Players try to come to an agreement for the distribution of the objects • Bargaining solution is the way in which the players divide the outcome • Types of Bargaining Solution: • Nash Bargaining Solution (NBS) • Kalai-Smorodinsky Bargaining solution (KBS) • Egalitarian Bargaining solution (ESS) Thesis Defense

13. Outline • Background • BitTorrent • Vehicular Communications and Wave • Game Theory and Bargaining • Proposed Scheme • WAVE model • Problem Formulation • Proposed Solution • Simulation Results • Conclusion and Future Work • References Thesis Defense

14. WAVE • WAVE is the latest technology under study to be implemented in vehicular communication for safety • Main objective : • provide connections with the applications in the vehicle and between the wireless devices in quickly changing environment and • exchange of information must be completed in very short time What is the Problem? • Fast Changing Environment - > Short Duration of Communication • Difficult to transmit huge amount of data between vehicles, and between vehicles and fixed infrastructure • Challenging to avoid overloading on RSU • Prioritizing the data to be transmitted first Thesis Defense

15. Proposal • Propose using the concept of BitTorrent for data distribution from fixed infrastructure to vehicles which eliminates the problem associated with huge size, short duration and server overloading • Propose Bargaining for data exchange between different vehicles which overcomes problems related to fairness • Propose algorithm for data dissemination from RSU for different priorities depending on the traffic pattern Thesis Defense

16. WAVE Model • Assumed values • Two vehicles are moving in opposite direction • Bit error rate = • Total packets to distribute = L • Size of each packet = M • If k<l, w (k) > w (l) i.e. high priority data will be transmitted first • Number of packets transmitted, • where • R= transmission rate • t0 = transmission time Thesis Defense

17. How Road Side Units Distribute Information? Answer: Bit Torrent RSU in Gas Station How On Board Units Exchange Information? Answer: Bargaining RSU in Toll Booth Problem Formulation • OBUs are located in vehicle and RSUs (eg:Toll Booth) are generally stationary • Difficult to transmit all L packets in short time • RSU randomly distribute the packets to OBUs and OBUs exchange information Thesis Defense

18. OBU Problem Formulation • How do OBUs exchange information between two vehicles? Utility of ith vehicle, where Ii = set of packets that vehicle i possess wi (k) = weight of the kth packet of vehicle I F = represents social welfare ni,j = maximum number of packets that can be exchanged within the time (t0) Thesis Defense

19. Start Neighbor Discovery Negotiation Call Bargaining Algorithm Data Transmission Monitor channel and adjust channel and coding rate Bargaining between OBUs • Data exchange Algorithm Both OBUs have same set of packets? Is channel good? Yes No No Yes Stop Thesis Defense

20. Input : Weight of available packet from OBUs, transmission rate Sort packets according to their weights Define a set of number of transmitted packets by OBUs Use Bargaining Solution Output : The numbers of packets to be transmitted by OBUs NBS: KBS: EBS: Bargaining Algorithm Thesis Defense

21. RSU Problem Formulation 2. How do RSUs distribute information? • L packets to be distributed =probability of packet l to be sent by RSU to OBU • Objective is to maximize overall utilities by changing PDF (Probability Distribution Function) Thesis Defense

22. Data Dissemination by RSU • The probability distribution needs to be optimized • Assumption : Weight of packet is ordered and probabilities corresponding to different packets have following relation whereand • β= 1; uniform distribution is obtained; cars have sufficient opportunities to exchange information • β = small, Geometric distribution, traffic load is light and high priority packets should be transmitted; cars have less opportunity to meet other cars Thesis Defense

23. Simulation Parameter Setting Thesis Defense

24. Simulation Results Fig. Transmission rate between two vehicles under different speeds • As two vehicles approach each other, Tx rate increases • Flat top – Highest transmission rate • Slower vehicle has long duration of data transmission Thesis Defense

25. Simulation Results Fig. Bargaining Solutions • Nash Solution occurs where max U1 *U2/ U1 intersects Pareto optimality, Pareto optimality (no user can improve without hurting the others) • Egalitarian Solution is located close to Nash Solution • Kalai-Smorodinsky is located at point with similar utility Thesis Defense

26. Simulation Results Fig. Utilities at equal intensity • Same intensity in both lanes • Utility of Nash is close to that of Egalitarian but of KS is different Thesis Defense

27. Simulation Results • As traffic intensity increases, exchange of data is more often but after a time, no files need to be exchanges so utility is constant • Symmetric – U2>U1 as vehicles in lane has high amount of high priority data to be sent to lane 2 • Asymmetric – U1<U2 as vehicles lane 1 has high traffic intensity than lane 2 Fig. Utility of vehicle under Nash Solution Thesis Defense

28. Simulation Results Fig. Utility of the vehicles under different data distribution • Case 1: Probability distribution for data sent to vehicle in lane 2 is varied • Case 2: Probability density for data sent to both lanes are varied Thesis Defense

29. Outline • Background • BitTorrent • Vehicular Communications and Wave • Game Theory and Bargaining • Proposed Scheme • WAVE model • Problem Formulation • Proposed Solution • Simulation Results • Conclusions and Future Works • References Thesis Defense

30. Conclusion • Tried to solve the problem of distributing large files to vehicular environment between cars and road side unit • Using game theoretical approaches • Distributed data to different cars • Exchange information among cars • Extensive simulations • Depending on the traffic model, the parameter beta changes for road side unit to distribute data • If traffic conditions in both lanes of highway is not different then, Nash and Egalitarian can provide fair solution Thesis Defense

31. Future Works • Communication method between RSU with other RSU will be studied • Exchange of data between OBUs far away will be studied • Exchange of data between OBUs moving in same direction will be studied • Implementation of this work in biology to study the behavior of animals remotely and perform data analysis will be studied • Implementation of this work in medicine to obtain information about the patients remotely which will give them flexibility will be studied Thesis Defense

32. Acknowledgements • Committee Members • Dr. Jacob Baker (Current Chair) • Dr. John Chiasson • Dr. Nader Rafla • Dr. Zhu Han (Former Advisor and Chair) • Dr. Ekram Hossain, University of Manitoba, Canada • Dr. Dusit Niyato, Nanyang Technological University, Singapore • Electrical and Computer Engineering Department Thesis Defense

33. Outline • Background • BitTorrent • Vehicular Communications and Wave • Game Theory and Bargaining • Proposed Scheme • WAVE model • Problem Formulation • Proposed Solution • Simulation Results • Conclusions and Future Works • References Thesis Defense

34. References • B. Shrestha, D. Niyato, Z. Han, and E. Hossain, “Wireless Access in Vehicular Environments Using BitTorrent and Bargaining”, GlobeCOMM ’08. • C. C. Kellum, “Six Application Mechanisms Required for Wireless Access in Vehicular Environments (WAVE),” In Proceedings of IEEE Vehicular Technology Conference, Dublin, Irland, Spring 2007. • S. Eichler, “Performance Evaluation of the IEEE 802.11p WAVE Communication Standard,” In Proceedings of Vehicular Technology Conference, Baltimore MD, Fall 2007. • B. Cohen, “Incentives Build Robustness in Bit Torrent,” In Proceedings of the 1st workshop on Economics of Peer-to-Peer systems, Berkeley CA,June 2003. • C. Aperjis and R. Johari, “A Peer-to-Peer System as an Exchange Economy,” In Proceedings of the 2006 Workshop on Game theory for Communications and Networks, Pisa, Italy, October 2006. • T. S. Rappaport, Wireless Communications: Principles and Practice, 2nd edition, Prentice Hall, 2002. D. Fudenberg and J. Tirole, Game theory, MIT Press, Cambridge, MA, 1991. • D. Jiang, L. Delgrossi, “IEEE 802.11p: Towards an International Standard for Wireless Access in Vehicular Environments”, Vehicular Technology Conference, 2008. VTC Spring 2008.IEEE Thesis Defense

35. Questions? Thank you. Thesis Defense

36. Data 7 7 Data 5 5 Data 6 6 Data 3 3 Data 4 Query 4 4 Data 4 Data Query Data Send Query 8 1 2 New Node Requesting Data 3 and 6 Query Data 1 Data 2 Unstructured Network Back Thesis Defense

37. NBS : EBS: KSS: Bargaining between OBUs (contd…) Start Input: Weight of packets, transmission rate Sort packets and Define a set of transmitted packets Return number of packets to be transmitted Thesis Defense

38. M. H. Ahmed, H. Yanikomeroglu, and S. Mahmoud,``Fairness Enhancement of Link Adaptation Techniques in Wireless Networks,“ In Proceedings of {\em IEEE Vehicular Technology Conference}, vol.~4, pp.1554-1557, Orlando FL, Fall, October 2003. Thesis Defense