Chapter 18: Wireless Infrastructure Flashcards
An AP that offers one or more fully functional, standalone basic service sets.
Autonomous AP
What must an autonomous AP be configured with to enable remote management?
Management IP
T/F
A dedicated management VLAN must be added to every trunk link to reach an autonomous AP.
True
T/F
Autonomous APs become easier to manage and configure as the wireless network expands.
False
As the wireless network expands, the infrastructure becomes more difficult to configure correctly and becomes less efficient.
T/F
Wireless traffic can travel between autonomous APs without having to travel across the wired network.
True
An AP that must join a WLC to become fully functional.
Lightweight
Define split-MAC architecture
The AP handles most of the real-time 802.11 processes and the WLC performs the management functions.
What is used to logically connect an AP and a WLC?
CAPWAP tunnel
A topology where the WLC is placed in a central location to maximize the number of APs that can be connected to it.
Centralized/Unified WLAN
What kind of link is used to connect a lightweight AP to an access layer switch?
Access link
T/F
Wireless traffic can travel between lightweight APs without having to travel across the wired network.
False.
Traffic is carried across the CAPWAP tunnel to the WLC.
Round-Trip Time (RTT) between AP and WLC
Less than 100ms
What can occur if the RTT between AP and WLC is too high?
The APs might decide the WLC is not responding fast enough. This can cause the AP to disconnect and find a faster WLC to connect to.
A wireless topology where the WLC is embedded in the switch hardware.
Embedded WLAN.
Benefit of embedded topology
Cost-effective
Mobility Express topology
A Cisco AP also runs software that acts as a WLC.
How many APs can a Mobility Express WLC support?
100
List the AP State Machine Steps
- AP boots
- WLC discovery
- CAPWAP
- WLC Join
- Download image
- Download config
- Run state
- Reset
T/F
Lightweight AP software can be manually controlled from the WLC.
False
The WLC that the AP connects to determines the software the lightweight AP runs.
What methods does a AP use to build a list of available WLCs to join?
- Prior knowledge of WLCs
- DHCP and DNS info to suggest some controllers.
- Broadcast on local subnet to solicit controllers.
An AP send a CAPWAP Discovery Request as :
A. Unicast
B. Multicast
C. Broadcast to local subnet
A. Unicast
OR
C. Broadcast to local subnet
What port is used for a CAPWAP Discovery Request?
A. TCP 5246
B. UDP 5246
C. TCP 5247
D. UDP 5247
B. UDP 5246
What ports does CAPWAP use?
5246 (Control)
5247 (Data)
CAPWAP is described in which RFC?
A. 5545
B. 3261
C. 5321
D. 5415
D. 5415
What do WLCs respond to a CAPWAP Discovery Request with?
CAPWAP Discovery Response
What does an AP send to a WLC when it tries to join the WLC?
CAPWAP Join Request
What determines the number of APs that a WLC can support?
Platform or License
List the 4 AP priority values.
Low
Medium
High
Critical
Default keepalive interval
30 seconds
What happens if an AP does not detect a response to a keepalive?
The AP sends 4 more keepalives at 3-second intervals.
List the AP modes
Local Monitor FlexConnect Sniffer Rogue detector Bridge Flex+Bridge SE-Connect
A measure of how effectively an antenna can focus RF energy in a certain direction.
Gain
The electrical field wave’s orientation.
Polarization
What occurs if the transmitter polarization does not match the receiver polarization?
Signal loss
2 types of antennas
Omnidirectional
Directional
Why do directional antennas have a higher gain than omnidirectional antennas?
They focus RF energy in one general direction.
What type of antenna gives the highest gain of all WLAN antennas?
Parabolic dish antenna
