A wireless engineer is designing a wireless network to support real-time applications over wireless.
Which IEEE protocol must the engineer enables on the WLC so that the number of packets that are
exchanged between an access point and client are reduced and fast roaming occurs?
A.
802.11w
B.
802.11r
C.
802.11i
D.
802.11k
Correct Answer: B
Explanation:
The IEEE 802.11r protocol, also known as Fast BSS Transition (FT), is designed to support real-time
applications by enabling faster roaming between APs. This protocol reduces the number of packets
exchanged during the reauthentication process when a client moves from one AP to another, thus
ensuring a more seamless transition and maintaining the quality of service required by real-time
applications such as voice and video conferencing. Reference: Designing Cisco Enterprise Wireless
Networks (ENWLSD 300-425
Question #2 (Topic: demo questions)
An engineer is designing a wireless deployment for a university auditorium. Which two features can
be used to help deal with the issues introduced by high AP count? (Choose two.)
A.
TSPEC
B.
RXSOP
C.
TPC
D.
LSS
E.
DFS
Correct Answer: B, C
Explanation:
RXSOP (Receive Start of Packet Detection Threshold) and TPC (Transmit Power Control) are two
features that can help manage the challenges associated with a high AP (Access Point) count in a
dense environment like a university auditorium. RXSOP can be adjusted to refine how APs
differentiate between noise and valid packets, which is particularly useful in high-density areas
where multiple APs might otherwise respond to the same signal. TPC helps in managing the transmit
power of APs, allowing for better coverage and reduced interference among APs that are in close
proximity to each other. Reference: Designing Cisco Enterprise Wireless Networks (ENWLSD 300-425
Question #3 (Topic: demo questions)
A customer asks an engineer to explain the concept of mobility domains and mobility groups. Which
statement does the engineer respond with?
A.
A mobility group does not constrain the distribution of security context of a client and also does not constrain AP fail-over between controllers when the WLC are in the same mobility domain.
B.
If WLCs are in the same mobility domain, they communicate with each other but, if an anchor WLC is present it must be in the same mobility domain for communication to be possible.
C.
If WLCs are in the same mobility domain, they communicate with each other. Mobility groups constrain the distribution of security context of a client and also constrain AP fail-over between controllers.
D.
WLCs do not need to be in the same mobility domain to communicate with each other. Mobility groups constrain the distribution of security context of a client and also constrain AP fail-over between controllers.
Correct Answer: C
Explanation:
Mobility domains and mobility groups are concepts used in Cisco wireless networking to manage
client roaming and controller interaction. When Wireless LAN Controllers (WLCs) are part of the
same mobility domain, they share a common database, allowing them to communicate and facilitate
seamless client roaming. A mobility group is a subset of this domain, where specific WLCs work
together more closely to share client context and security credentials. This ensures that when a client
roams from one access point (AP) to another across different controllers, the authentication and
security context are maintained, allowing for a seamless transition without the need to re
authenticate.