Term
| What are the names of the radio frequency bands what WLANs operate on? |
|
Definition
ISM - Industrial, Scientific, Medical U-NII - Unlicensed National Information Infrastructure |
|
|
Term
| At what frequency band do most cellphones operate? |
|
Definition
|
|
Term
| At what frequency do 802.11b/g/n WLANs operate? |
|
Definition
|
|
Term
| At what frequency do 802.11a/n WLANs operate? |
|
Definition
|
|
Term
| What are the pros & cons of operating at a higher frequency band for WLAN? |
|
Definition
pros: avoids many common sources of 2.4GHz emissions/interference; smaller antennas and larger antenna gain cons: more easily absorbed by structures, thus reducing range |
|
|
Term
What does OFDM stand for? Which wireless standards incorporate it? What is the max speed it allows? |
|
Definition
Orthogonal Frequency Division Multiplexing 802.11a/g/n 54 Mbps |
|
|
Term
What does DSSS stand for? What does it do? What is the max speed it allows? |
|
Definition
Direct Sequence Spread Spectrum method of using available wireless channels that result in channels 1, 6, & 11 being used to overlap coverage without interference 11 Mbps |
|
|
Term
| What happens when 802.11b ang 802.11g coexist in the same network? |
|
Definition
| Performance of g radios are impaired by the b radios |
|
|
Term
How many available channels are in the following wireless standards: 802.11a 802.11b 802.11g 802.11n |
|
Definition
802.11a - 23 802.11b/g - 11
802.11n - 11 or 23 |
|
|
Term
What are the approximate range of the following wireless radios: 802.11a 802.11b 802.11g 802.11n |
|
Definition
802.11a - 75 ft 802.11b/g - 150 ft 802.11n- 500 ft |
|
|
Term
What are the characteristics of the Ad Hoc WLAN operational mode? What kind of service set is this known as? |
|
Definition
Connection between wireless devices/clients without requiring an AP aka. IBSS |
|
|
Term
| What are the characteristics of the Infrastructure WLAN operational mode? |
|
Definition
Wireless client devices must sent through an AP The AP provides the connection to the wired LAN |
|
|
Term
| What are the characteristics of the Autonomous Infrastructure WLAN mode? |
|
Definition
| each AP is managed separately and forwards client data into network directly |
|
|
Term
| What are the characteristics of the Lightweight Infrastructure WLAN mode? |
|
Definition
each AP associates with a WLAN controller client data is tunneled through the controller |
|
|
Term
| What does BSS stand for and what are its characteristics? |
|
Definition
Basic Service Set single AP that provides network connectivity for associated clients each AP offers separate WLAN no roaming |
|
|
Term
| What does ESS stand for and what are its characteristics? |
|
Definition
Extended Service Set each AP defines a BSS, and a group of AP/BSS forms an ESS clients can roam between overlapping BSS without losing connection to the ESS |
|
|
Term
| What is the role of a SSID? |
|
Definition
name that identifies the WLAN for an ESS |
|
|
Term
What are the characteristics of the following WLAN security threats: War Driving Internal Rogue APs |
|
Definition
War Driving - connecting to unsecured APs for free wireless access Internal - malicious or ignorant actions from users within the network
Rogue APs - put in place a WLAN without authorization
|
|
|
Term
| What are the three main security methods for WLANs? |
|
Definition
(Mutual) Authentication Encryption Intrusion Detection/Prevention |
|
|
Term
What does WEP security standard involve? What are its vulnerabilities? |
|
Definition
uses a static preshared key cons: administratively difficult to change keys for entire network/clients; weak encryption |
|
|
Term
| What were the three key improvements in Cisco's interim solution to WEP vulnerabilities? |
|
Definition
Dynamic Key Exchange - key dynamically agreed on by devices instead of statically preshared User Authentication with 802.1x - user/password required to connect Unique Key per Packet - encyrption key for packets changes with every packet |
|
|
Term
| What does WPA security standard involve? |
|
Definition
similar to Cisco's interim solution to WEP: Dynamic keying via TKIP (Temporal Key Integrity Protocol) Authentication with PSK or 802.1x |
|
|
Term
| What does 802.11i/WPA2 security standard involve? |
|
Definition
Included features for dynamic keying, authentication, and strong encryption using AES (Advanced Encryption Standard) Not backward compatible with WPA |
|
|
Term
| What are the basic steps to configuring WLAN? |
|
Definition
1. verify wired network that the AP will connect to 2. install AP 3. configure wireless settings 4. install & configure wireless client 5. verify client access 6. configure security 7. verify client access
|
|
|
Term
| What needs to be consistent on all APs belonging to the same ESS? |
|
Definition
|
|
