IT220P
Homework
Chapter 11 (#1-39)
1. List 2 advantages of wireless networking.
User mobility in the workplace and a cost effective networking media for use in areas that are difficult or too costly to wire.
2. What are the 3 areas defined for the IEEE 802.11 standard?
It defines the physical layer, the MAC, and the MAC management protocol and services.
3. What is an ad hoc network?
Another term used to describe an independent network.
4. What is the purpose of an extended service set?
To extend the range of mobility by adding multiple access points to the network.
5. What are the 4 physical layer technologies being used in 802.11 wireless networking?
Direct sequence spread spectrum (DSSS), frequency hopping spread spectrum (FHSS), infrared, and orthogonal frequency division multiplexing (OFDM).
6. Describe the frequency spectrum for the DSSS channels in 802.11wireless networking.
It implements 14 channels (each consuming 22 MHz) over approximately 90 MHZ of RF spectrum in the 2.4 GHz ISM band.
7. Define a pseudorandom sequence as it applies to FHSS.
Pseudorandom means the sequence appears random but in fact does repeat overtime. In FHSS it uses 79 channels (each 1 MHz wide) in the ISM 2.4GHz band and uses a hopping sequence.
8. What must the FHSS transmitting and receiving units know to communicate?
It must know the hopping sequence.
9. What is the frequency range used by 802.11a, and what modulation technique is used?
It operates in the 5 GHz range and uses a technique called orthogonal frequency division multiplexing (OFDM) to transport the data over 12 possible channels in the U-NII.
10. What is the maximum data rate for the following?
a. 802.11b
b. 802.11a
c. 802.11g
d. 802.11n
11. Define MIMO as it applies to 802.11n
MIMO is a space-division multiplexing technique where data stream is split into multiple parts called spatial streams. In 802.11n in doubling the spatial stream doubles the effective data