1. Administrivia
  o Class will meet in Gates 498
  o Grade: 10% first assignment, 20% writeups, 20% class participation, 50% final project
  o Class format: discuss papers
    - expect you have read them carefully
    - understand the material
    - if you don't, then put questions in writeup
    - or, chase references! web is your friend

2. Topic: routing
  o unicast communication between pairs of nodes in a wireless network
  o link estimation, route selection
  o routing state
  o geographic, virtual coordinates, etc.

3. Systems
  o Wireless has a long (and bad) history
  o So we focus on real protocols on real nodes

3. Final projects
  o Goal: piece of research
  o Examples
    - Take routing protocol we read, re-implement, improve
    - Invent new routing protocol
    - Derive new bounds for compact routing
  o Write a 10-page conference-style paper
  o Groups or individual

-----------

1. Moore's law -> calm computing
  o What will the world look like when there's 1000 computers/person?
  o Cannot require human intervention
  o Sense and interact with the environment

2. Mark Weiser's paper
  o Vision of what computing will be like in 2011
  o Ubiquitous computing
  o Where do his projections overshoot?
  o Where do they undershoot?
  o How are computing problems different today than then?

3. Ultra-low power wireless
  o Where this is going
  o "On the other hand, the transparent linking of wired and wireless networks is an unsolved problem. Although some stop-gap methods have been developed, engineers must develop new communication protocols that explicitly recognize the concept of machines that move in physical space."   
  o Need nodes to be able to communicate efficiently 
  o All sorts of issues (scale, variation, interference) you do not encounter in standard networks

4. Routing
  o Problem of delivering packet from A to B
  o Turns out to be very hard!
  o Wireless networks are not a graph
  o *Time* matters: latency, transmission timing, etc.
  o *Routing state* matters
  o *Stretch* (efficiency) matters

5. Telos paper
  o Describes the hardware platform we'll be playing with
  o Defacto standard in low-power wireless research
  o Gives history on evolution of low-power wireless platforms

6. What points does the paper focus on?
  o RAM and code size
    - Claim that these remain constant
    - Is this true?
  o Radio properties
    - Packet-level
    - "Loses flexibility:" does this matter?
    - Speed: does this matter?
    - Energy 
    - Let's look at these graphs
      * Are they misleading?
  o Energy
    - Let's look close at the numbers
    - Why W in some places, A in others?
    - Is W reasonable?