Implementing Cisco Unified Wireless Networking Essentials (IUWNE)


Wireless Fundamentals
  • Amplitude is the name of the distance between the higher crest of a wave and the lower crest.
  • 1 kHz is the frequency of a signal that occurs 1,000 times per second.
  • Scattering term describes the spreading of a signal in multiple directions by small particles.
  • SNR term describes the amount by which a signal is better than the noise level.
  • For a signal to be good, the RSSI level must be as high as the SNR level.
  • WMAN is type of wireless network which covers an area the size of a city.
  • WLAN is type of wireless network which extends LANs.
  • Repeater device can be used to extend the range of an AP.
  • Wireless coverage area of an AP is a BSA.
  • System in which a wired network links two APs is an ESS.
  • EIRP does not relate only to omnidirectional antennae.
  • 200 mW is equivalent to 23 dBm.
  • Effective Isotropic Radiated Power is EIRP.
  • There is no direct conversion between dBm and dBi.
  • Side view of the antenna radiation pattern describes an elevation chart.
  • The magnetic field oriented in comparison to the electric field is 90 degrees to the left.
  • Multiple antennas is used to try to solve multi-path issues.
  • RP-TNC connector is used on Cisco APs.
  • The radiated signal is weaker is one disadvantage of using a splitter.
  • Narrows the vertical beam is the effect of increasing the gain of an omnidirectional antenna.
  • 5.5 Mb/s rate is a DSSS speed.
  • Barker 11 transform each bit of the data into an 11-bit chip that is to be sent.
  • DSSS use sending a wide signal spread of 22 MHz method to combat interference.
  • OFDM uses small carriers instead of a large one of DSSS.
  • An AP sends a special beacon with duration set to 32768 start DCF mode.
  • CSMA/CA layer 2 technique is used in wireless networks.
  • A client must wait duration of client NAV before being able to send a frame in the normal operation of a cell.
  • An 802.11 header contains a maximum of four MAC addresses.
  • RA is address of the station to receive the frame.
  • A wireless ACK sent after each data frame.
  • The control field gives information about frame type.
  • The SSID usually found in beacon and authentication requests frames.
  • 802.15.1 IEEE protocol relates to Bluetooth.
  • Network coordinator device in a ZigBee network sends beacons.
  • 5 miles is the range of 802.16e.
  • Create regulations is the role of the FCC.
  • 20 dBm is the maximum EIRP in the 2.4-GHz band, per ETSI rules.
  • 19 non-overlapping 802.11a channels are available in Europe.
  • 11 Mb/s rate is an 802.11b speed.
  • MIMO is new wireless modulation and technique that is used to gain longer range and higher speed.
  • 4 non-overlapping 802.11b/g channels are available in Europe.