The network administrator receives complaints of slow wireless network performance and performs a sniffer trace of the wireless network in preparation for migration to 802.11n. The sample capture shows frames that contains AP beacons with NonERP_Present bit set to 1 and frames with RTS/CTS.
Which two conclusions can be interpreted from these frames? (Choose two.)
A . The network is performing slowly because 802.11n clients are already mixed with 802.11g clients.
B . The network is performing slowly because 802.11b clients still exist in the network.
C . The network is performing slowly because a wireless client is incorrectly configured, which results in RF interference.
D . Possible 802.11b wireless clients are located only in the AP cell radius where the sniffer capture was performed.
E . Possible 802.11b wireless clients could be located anywhere in the wireless network.
Answer: BE
Explanation:
If an ERP AP hears a beacon from an AP where the supported data rates contain only 802.11b or 802.11 DSSS rates, it will enable the NonERP_Present bit in its own beacons, enabling protection mechanisms in its BSS. In simpler terms, if an 802.11g AP hears a beacon frame from an 802.11 or 802.11b access point or ad hoc client, the protection mechanism will be triggered.
http://mrncciew.com/2014/11/02/cwap-802-11-protection-mechanism/