1. 1 Wireless Networking & Mobile Computing ECE 256, CS 215 Spring 2009 Romit Roy Choudhury Dept. of ECE and CS

2. 2 Course Logistics

3. 3 Welcome to ECE 256 Timings: Tu/Thu 11:40am to 12:55pm Location: 216 Hudson Hall Course TA:Rahul Ghosh rahul.ghosh@duke.edu Office hours: Wed 2:30 - 4:00pm Insructor: Romit Roy Choudhury Ph.D from UIUC in Summer, 2006 Research in Networks, Dist Sys, Mobile Comp. Email me at romit@ee.duke.eduromit@ee.duke.edu Visit me at 203 Hudson Hall

4. 4 Welcome to ECE 256 Prerequisite:ECE 156 or CS 114 Else, come and talk to me Grading:  Participation/Presentation:10%  Homework (Paper reviews, etc.):20%  1 mid-term exam:20%  Semester-long project:50%

5. 5 Welcome to ECE 256 Class broadcast email: ece_256_01@ee.duke.edu Course Website: http://www.ee.duke.edu/~romit/courses/s09/ece256-sp09.html  Most course related information will be posted on the website Please check course website frequently

6. 6 Welcome to ECE 256 Make up classes  Will be occasionaly necessary due to travel  Would like to schedule on a case by case basis

7. 7 Course Contents

8. 8 Shifting Trends The edge of the internet becoming wireless  Single hop networks  Multi-hop networks

9. 9 Many Benefits due to Wireless Significantly lower cost  No cable, low labor cost, low maintenance Ease  Minimum infratructure - scatter and play Unrestricted mobility  Unplugged from power outlet Ubiquity  Available like water/electricity - holy grail

10. 10 If everything goes right, the future will be “An invisible Internet hanging from a visible Internet …”

11. 11 The Future RFID and Sensor Networks Citywatchers, Walmart Intel, Philips, Bosch … Personal Area Networks Motorola, Intel, Samsung … Mesh Networks and Wireless Backbones Microsoft, Intel, Cisco … Internet

12. 12 But, what does it take for that mobile/wireless future to become feasible?

13. 13 Research PHY MAC / Link Network Transport Security Application Incentives Channel fluctuations Spatial Reuse Mobility Energy Savings Eavesdropping Loss Discrimination Privacy Ubiquitous Services Interference Mgmt. Enabling wireless ubiquity. Showing what is feasible, and what is not … Enabling wireless ubiquity. Showing what is feasible, and what is not … Applications that exploit ubiquity and mobility. Challenges underlying such applications Applications that exploit ubiquity and mobility. Challenges underlying such applications

14. 14 Research PHY MAC / Link Network Transport Security Application Incentives Channel fluctuations Spatial Reuse Mobility Energy Savings Eavesdropping Loss Discrimination Privacy Ubiquitous Services Interference Mgmt. Wireless Networking Wireless Networking Mobile Computing Mobile Computing

15. 15 This Course Introduces fundamentals of wireless channel  The departure from wired networks …  Emerging innovations in EE, communications area Exposes implications on protocol design  At MAC, Network, Transport, Security  Investigates gap between idea and and actual system  Considers theoretical aspects Envisions new mobile computing applications  Identifies challenges underlying them  Resolves these challenges into a full system solution Allows you to design/develop your own ideas  Ideally extending the state of the art

16. 16 At the End of this Course … You understand  Physical layer (radios, rate, antennas, channels)  MAC protocols (who gets the chance to talk)  Routing (path selection algorithms and issues)  Reliability (wireless congestion control, rate control)  Security (attackers may overhear, pretend, misbehave)  Applications (social networks, personal networks, P2P networks)  Application related challenges Localization (extracting the location of a device) Mobility (how it helps and disrupts communication) Privacy (how to protect a user from being tracked)  Energy-awareness (how it percolates various network functions)  Emerging Topics (interference cancellation, multicast, rural nets)  Capacity (what is feasible, what are performance bounds)

17. 17 What this Course Does Not Cover Not a wireless communications course Does not cover  Modulation schemes  Transmitter/Receiver design  Signal processing and antenna design  Source coding / channel coding  Etc. This is course on  Design, analysis, and implementation of protocols and algorithms in (mobile) wireless network systems

18. 18 Some other Thoughts Dilemma 1.Teach very advanced stuff for the networking pro 2.Teach from absolute scratch for the uninitiated I will try to strike a balance Please bear with me if materials are sometimes too easy/difficult for YOU

19. 19 Course Structure

20. 20 Course Structure I will present most lectures and papers  You present once in entire semester (30 minutes)  2 students present in one class For every class, read 2 of assigned papers  Write reviews for each and email TA before class  Bring printed copy to class  A random set of reviews will be graded :) Several recommended readings  Make an effort to read them  I understand that you cannot do so always

21. 21 Course Structure 1 open-book mid term, No Final Exam  Tentative date of mid-term: Mar 31 Semester-long class project  In groups of 2 (max 3)  Focus on this from early on Class ends with a final project poster/demo  Submit conference-style paper  Prize for 3 best projects Potentially funded by industry

22. 22 Class Participation / Presentation, Reading Assignment, and Course Project

23. 23 Participation / Presentation Ask lots of questions. Period.  I strongly encourage you to ask, disagree, debate Class presentation  You present one paper (30 minutes)  Pick an open slot (ones not marked “Romit”) Earlier you pick, more options you have to choose from Deadline is Jan 22, 2008 Email me your choice of paper (and date)  Don’t worry about not knowing the topic of ppt By that time, you will know enough

24. 24 Reading Assignment Read the papers assigned for reading  Critic / Review them carefully  Reviews should not be more than a page Email reviews to TA + Bring a hard copy to class Random set of reviews will be graded  I might upload selected reviews on a webpage

25. 25 Thoughts on Reading Papers Know why you are reading the paper  Reading for absorbing concepts (class assignment) Read fully, think, reread, ask, challenge  Reading for excitement (deciding project topic) Read initial parts, don’t try to understand everything, get a feel  Reading for problem identification Read the problem carefully  Reading to discriminate (before finalizing project) Read solution, ensure your ideas different, analyse performance Most Important Most Important

26. 26 Course Research Projects Projects consist of 3 parts:  Problem identification  Solution design  Performance evaluation Each paper you read is someone’s project  Many papers are actually student’s class projects  Read them critically  Ask yourself Is the problem really important ? Should you care ? Is the solution sound ? Under what assumptions? Do you have other (better) ideas ? Is evaluation biased ? Are reults shown only in good light?

27. 27 More on Projects Discuss your thoughts, ideas with me  They need not be cooked, and can have many flaws  Statistically, every 18 ideas lead to one decent idea If you like an area / direction  Read many many related papers Don’t try to come up with a quick solution  Ensure your problem is a new, real problem  Finding the solution is typically easy

28. 28 More on Projects Protocol evaluation typically requires coding  Think what you would like to do  Options are: Coding on real devices (like sensors, phones, routers) Coding in existing network simulators (ns2, Qualnet, etc.) Coding your own simulator Theoretical projects involve MATLAB, CPLEX, etc. Project ideas take time … think now and then  Spending 3 hours for 10 days better than 10 hours for 3 days

29. 29 More on Projects Find a project partner early  Discuss reviews, papers, potential project themes Class project often bottlenecked by platform  Think of the evaluation platform during project selection  If you are not familiar with the Linux OS, it’s a bad idea to do a project involving router-prorgamming

30. 30 Some Closing Thoughts This class is about research  Be active, ask questions, debate, and disagree Don’t worry too much about grades  It does not matter as much as you think Read a lot - this is a hot research area  If you are hunting for MS/PhD area, read even more Interact with me  Even if you have ZERO clue of what’s going on

31. 31 Hello! I am ECE 256 Any Questions?

32. 32 ECE 256 Assignment 1 Watch: Assignment Due: Tuesday, Jan 22 Group work allowed Theater preffered, TV acceptable

33. 33 Questions ?

34. 34 Welcome to ECE 256 Please fill up student survey  Helps me in designing the course better

35. 35 Towards Ubiquity Focus on wireless multihop networks  Initial applications in military  Emering commercial technologies and applications For example … B A C D