Wireless Flashcards
What is the Law of Zero?
Law of Zero is a value of 0 dB which means the two absolute power values are equal.
What is the Law of 3s?
Law of 3s is a value of 3dB which means that the power value of interest is double the reference value. -3 is half
What is the Law of 10s?
Law of 10s is a value of 10dB which means that the power value of interest is 10 times the reference value.
What is EIGP?
Effective isotropic radiated power (EIRP) is the actual power level that will be radiated from the antenna.
Free space loss is a function of what two values?
Free space loss is a function of distance and frequency only.
What is RSSI?
Received signal strength indicator (RSSI) is a receiver’s measured
What device makes the decision for a wireless client to roam from one AP to another?
The Client device decides when to roam to another AP.
What is the next step after an AP boots up?
The next step after an AP boots would be to discover a WLC.
After an AP discovers the controller, what is the next step?
After an AP discovers a controller to join it attempts to build a CAPWAP tunnel with the controller.
What are two client authentication modes that WPA supports?
WPA supports Pre-Shared Key (PSK) and 802.1x. These are also known as personal and enterprise modes respectively.
With personal mode, a key string must be shared or configured on which devices on the network?
The key string must be shared or configured on every client and AP before the clients can connect to the wireless network.
In EAP, what device is the middleman between the clients and the Authentication Server?
The WLC
in 802.1x, what is the supplicant?
Supplicant is the client device that is requesting access.
Who is the authenticator?
Authenticator is the network device that provides access to the network (usually a WLC)
What is the Authentication server (AS)?
The Authentication server (AS) is a device that takes user or client credentials and permits or denies network access based on the database and policies (usually a RADIUS server).
If a lightweight AP needs to download a new software image, how does it get the image?
AP gets the image from a WLC.
What kind of gain and beamwidth does an omnidirectional antenna usually have?
Omidirectional antenna usually has low gain and large beamwidth.
An AP in local mode does what?
Local mode is the default lighweight mode that offers one or more functioning BSSs on a specific channel. During times when not transmitting, the AP scans other channels to measure interference and other events,
When a client moves its association from one autonomous AP to another, it is actually leaving and joining which one of the following?
BSS
Ten lightweight APs are joined to a wireless LAN controller. If a client roams from one of the APs to another, which one of the following correctly describes the roam?
Intracontroller roaming
Which of the following provides the most efficient means for roaming, as measured by the time to complete the roam?
Intracontroller roaming
What authentication method does WPA2 personal mode use?
Pre-Shared Key
What is the authentication method when 802.1x is used on a WLAN?
EAP
A Cisco WLC is configured for 802.1x authentication, using an external RADIUS server. The controller takes on which one role?
WLC takes on the authenticator role.
