0. Logistics:
  * Lunch for Students Interested in Graduate School,
    Location: Warren Weaver Hall, Room 101,
    Time: Oct 2 (tomorrow) 12:30-1:45pm.
  * Assignment 2 (and correction) posted.
  * Clarification re: private posts on Piazza
1. Today: congestion control
  * Historic context for congestion collapse and congestion control
  * The goal of congestion control: get to the correct window size in a distributed manner.
  * AIMD/DECbit: One way to do this.
  * DECbit came first, but AIMD was simpler to implement (no router changes).
  * Slow Start vs. Congestion Avoidance: accelerating vs. maintaining speed.
2. Slow Start
  * Exponential increase, but slower than dumping a window.
  * Increase by one on every ACK, double every RTT.
3. Congestion Avoidance
  * Additive Increase
  * Multiplicative Decrease
  * Increase by one every RTT, instead of one every ACK.
4. Why AIMD?
  * Chiu-Jain plots.
  * Why not MIMD, AIAD, MIAD.
  * Example of control system (control based on feedback)