Outline for April 30, 2007

  1. Greetings and felicitations!
    1. Midterm has been moved to Friday, May 4. If this change causes problems for you, please come see me, or e-mail me, at once.
    2. Sample midterm is available on the web; so are the answers.
    3. Warning: no office hours on Wednesday of next week!
    4. I will hold a review session for Thursday, May 3, from 3:30-4:30 in 1227 Haring Hall.
    5. I will also hold special office hours on Thursday: 10:00-11:00AM. Also, don't forget I have office hours on Friday from 9:00-9:50AM.
  2. Wireless
    1. Your wireless card locates an access point (AP) connected to a LAN
    2. AP and your card handshake (and check that you're allowed to use that AP!), begin exchanging data
    3. Broadcast, so anyone can read your messages
    4. Many protocols, most from IEEE 802.11? family; 802.11b, 802.11g, 802.11n, 802.11x most common and offer different levels of security and speed
  3. Inside a network, from you to the wire
    1. Application layer converts message to bits and attaches sending and receiving computer
    2. Presentation layer converts bits to ASCII, compresses and encrypts (if you are encrypting)
    3. Session layer sets boundaries for a message
    4. Transport layer divides data into segments and creates checksums

Here is a PDF version of this document.