Lecture 16: Introduction to WLAN

Question 1

What is the difference between WLAN and WiFi?

Answer 1

WLAN can also rely on other forms of wireless technology

Question 2

How is IEEE standards, WiFi Alliance and WiFi related?

Answer 2

WiFi is a implementation of standards set out by IEEE

WiFi alliance acts as an approval body that ensures products meet the standards in a way that ensures compatibility and standards compliance

Question 3

How is IEEE standards, WiFi Alliance and WiFi related?

Answer 3

WiFi is a implementation of standards set out by IEEE

WiFi alliance acts as an approval body that ensures products meet the standards in a way that ensures compatibility and standards compliance

Question 4

The IEEE standards that govern wireless networking are typically known by their standard number ___

Answer 4

802.11

Question 5

What are the two distinct layer of the network stack that the 802.11 standards cover?

Answer 5

• Physical layer
  Handles radio transmitter and reciever, frequencies uses and modulation used to send data wirelessly
• Data link layer
  Handles MAC addressing

Question 6

What does the 802.11 standards for the physical layer tell us?

Answer 6

How to send data

• Specific frequency bands in use
• Modulation: how binary data is translated into a radio wave, transmitted and then de-modulated back into binary data by the receiver

Question 7

What does the 802.11 standards for the data link layer tell us?

Answer 7

How to manage the physical layer

• MAC addressing a form of physical addressing
• Responsible for packaging data in frames for transmission

Question 8

What problems do WLAN pose?

Answer 8

The issue of broadcast

Wireless traffic cant be aimed so your traffic is broadcast to everyone in the vicinity which makes security a difficult task