Routing in Sensor Networks: Directed Diffusion and other proposals

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

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Welcome to ECE 256

• Timings Tu/Thu 1140am to 1255pm
• Location 216 Hudson Hall
• Course TA Rahul Ghosh rahul.ghosh_at_duke.edu
• Office hours Wed 230 - 400pm
• Insructor Romit Roy Choudhury
• Ph.D from UIUC in Summer, 2006
• Research in Networks, Dist Sys, Mobile Comp.
• Email me at romit_at_ee.duke.edu
• Visit me at 203 Hudson Hall

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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

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Welcome to ECE 256

• Class broadcast email
• ece_256_01_at_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

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Welcome to ECE 256

• Make up classes
• Will be occasionaly necessary due to travel
• Would like to schedule on a case by case basis

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Course Contents
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Shifting Trends

• The edge of the internet becoming wireless
• Single hop networks
• Multi-hop networks

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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

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• If everything goes right,
• the future will be
• An invisible Internet hanging from
• a visible Internet

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The Future
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• But, what does it take for that
• mobile/wireless future to become feasible?

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

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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)

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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

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Some other Thoughts

• Dilemma
• Teach very advanced stuff for the networking pro
• 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

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Course Structure
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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

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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

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Class Participation / Presentation,Reading
Assignment,andCourse Project
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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)
• Dont worry about not knowing the topic of ppt
• By that time, you will know enough

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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

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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, dont 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
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Course Research Projects

• Projects consist of 3 parts
• Problem identification
• Solution design
• Performance evaluation
• Each paper you read is someones project
• Many papers are actually students 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?

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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
• Dont try to come up with a quick solution
• Ensure your problem is a new, real problem
• Finding the solution is typically easy

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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

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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, its a
  bad idea to do a project involving
  router-prorgamming

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Some Closing Thoughts

• This class is about research
• Be active, ask questions, debate, and disagree
• Dont 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 whats going on

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Hello! I am ECE 256 Any Questions?
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ECE 256 Assignment 1

• Watch
• Assignment Due Tuesday, Jan 22
• Group work allowed
• Theater preffered, TV acceptable

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• Questions ?

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Welcome to ECE 256

• Please fill up student survey
• Helps me in designing the course better

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Towards Ubiquity

• Focus on wireless multihop networks
• Initial applications in military
• Emering commercial technologies and applications
• For example

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