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Standardization role of the ITU-R |
Worldwide standardization of communications that use radiated energy, particularly managing the assignment of frequencies |
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Standardization role of the IEEE |
Standardization of wireless LANs (802.11) |
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Standardization role of the Wi-Fi Alliance |
An industry consortium that encourages interoperability of products that implement WLAN standards through their Wi-Fi certified program |
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Standardization role of the FCC |
The U.S. government agency that regulates the usage of various communications frequencies in the U.S. |
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As the FCC is controlled the U.S. government, the ITU-R is ultimately controlled by ___ |
the UN |
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Frequency band used by 802.11a |
5 GHz |
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Frequency band used by 802.11 b/g |
2.4GHz |
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802.11g speed using DSSS |
11Mbps |
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802.11g speed using OFDM |
54Mbps |
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Service set name for ad-hoc mode |
IBSS (independent basic service set) |
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Two service sets available in infrastructure mode? |
BSS (basic service set) |
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Difference between BSS and ESS? |
BSS = one AP |
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What are the three frequency ranges relevant to WLAN networks? |
900MHz, 2.4GHz, 5GHz |
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Three general classes of encoding signals used by WLANs |
FHSS, DSSS, OFDM |
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FHSS |
Frequency Hopping Spread Spectrum |
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DSSS |
Direct Sequence Spread Spectrum |
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OFDM |
Orthogonal Frequency Division Multiplexing |
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Which of the 802.11 standards use FHSS |
only the original 802.11 |
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What is the significance of using DSSS with an ESS WLAN? |
APs with overlapping coverage areas should be set to use different, non-overlapping DSSS channels |
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Which of the 802.11 stanards use DSSS |
802.11b |
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Which of the 802.11 standards use OFDM |
802.11a, 802.11g |
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SNR |
Signal to Noise Ratio |
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EIRP |
Effective Isotropic Radiated Power |
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EIRP, how is it calculated |
radio's output power, plus increase in power caused by the antenna, minus the power lost in the cabling |
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What is the algorithm used by WLANs to deal with the problem of collisions? |
CSMA/CA |
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CSMA/CA |
Carrier Sense Multiple Access / Collision Avoidance |
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What is the process used by WLANs (not CSMA/CA) to deal with collisions when they occur? How does this differ from the process used by wired networks? |
Each frame is required to receive acknowledgment. This is different in WLANs because they have no way of sensing if a collision has occured (as opposed to FCS used by wired networks) |
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SSID |
Service Set Identifier |
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When you configure an ESS WLAN, each AP should have (the same/different) SSID |
the same |
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How many maximum characters, and what character encoding is used for SSID? |
32 characters |
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CCX |
Cisco Compatible Extensions |
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What does the CCX program do? |
Allows any WLAN manufacturer to send its products to a third-party testing lab, with the lab performing tests to see if the WLAN NIC works well with Cisco APs |
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What percent of wireless NICs on the market have been certified through CCX? |
95 |
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ZCF |
Zero Configuration Utility |
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SWAN |
Structured Wireless-Aware Network |
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What does SWAN do/consist of? |
Many tools, some of which specifically address the issue of detecting and identifying rogue APs |
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Solution to the threat of wardrivers |
strong authentication |
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Solution to the threat of hackers stealing information in a WLAN |
strong encryption |
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Solution to the threat of employee AP installation |
IDS, including Cisco SWAN |
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Solution to the threat of rogue AP |
strong authentication, IDS/SWAN |
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WEP |
Wired Equivalent Privacy |
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IEEE standard which defines WPA2 |
802.11i |
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EAP |
Extensible Authentication Protocol |
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Who defined the original WPA standard? |
Wi-Fi Alliance |
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What year was WEP introduced? |
1997 |
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What year was WPA introduced? |
2003 |
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Main problems of WEP |
Static Preshared Keys lead to keys being changed infrequently |
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802.11x is what? |
The standard for end-user authentication used as part of the Cisco interim solution before 802.11i (WPA2) was introduced. |
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Three major features of the Cisco interim solution before 802.11i (WPA2)? |
Dynamic key exchange (instead of static preshared keys) |
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TKIP |
Temporal Key Integrity Protocol |
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T/F: Cisco's pre-WPA solution based on the (then-)unfinished 802.11i standard used the same TKIP as WPA |
False (it used a similar but proprietary protocol) |
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MIC |
Message Identity Check |
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T/F: Cisco's pre-WPA solution based on the (then-)unfinished 802.11i standard is compatible with WPA, assuming the correct settings are used |
False |
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T/F: WPA2 is backwards-compatible with WPA |
False |
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T/F: WPA2 uses the same TKIP encryption used by WPA |
False |
