Wireless Architecture Facts Flashcards
1
Q
Frequency Hopping Spread Spectrum (FHSS)
A
- Uses a narrow frequency band and hops data signal in a predictable sequence from frequency to frequency over a wide band of frequencies
2
Q
Direct-Sequence Spread Spectrum (DSSS)
A
- The transmitter breaks data into pieces and sends the pieces across multiple frequencies in a defined range
- Is more susceptible to interference and less secure than FHSS
3
Q
Orthogonal Frequency-Division Multiplexing (OFDM)
A
- Breaks data into very small data streams in order t send the information across long distances where environmental obstacles may be an issue
4
Q
OFDM Facts
A
- Modulates adjacent radio signals orthogonally, which allows for a very large number of small data streams in a single frequency
- Reduces he effects of signal interference caused by environmental obstacles, such as walls or buildings
- Is used by 802.11g/a/n and ac wireless networks to achieve higher transfer speeds
5
Q
Name the two Wireless Topologies
A
- Ad Hoc
* Infrastructure
6
Q
Ad Hoc
A
- Works in peer to peer mode without an access point
* The wireless NICs in each host communicate directly with one another
7
Q
Ad Hoc Facts
A
- Uses a physical mesh topology with a logical bus topology
- Is cheap and easy to set up
- Cannot handle a large number of hosts
- Requires special modifications to reach wired networks
- * typically us an ad hoc network to create a direct, temporary connection between two hosts**
8
Q
Infrastructure
A
- Uses an access point (AP) that functions like a hub on an Ethernet network.
9
Q
Infrastructure characteristics
A
- Uses a physical star top. with a logical bus top.
- You can easily add host without increasing administrative efforts (scalable)
- The AP can be connected to a wired network easily allowing clients to access both wired and wireless hosts
- The placement and configuration of APs require planning to implement effectively
*** You should implement an infrastructure network for all but the smallest of wireless networks
