A company is deploying a new wireless network and requires 800Mbps network throughput. Which of the following is the MINIMUM configuration that would meet
this need?
A.
802.11ac with 2 spatial streams and an 80MHz bandwidth
B.
802.11ac with 3 spatial streams and a 20MHz bandwidth
C.
802.11ac with 3 spatial streams and a 40MHz bandwidth
D.
802.11ac with 4 spatial streams and a 160MHz bandwidth
Explanation:
Spatial streaming is used in wireless communications where multiple-input-multiple-output (MIMO) is being used. With MIMO, multiple antennas are used for
transmission and reception. MIMO was available in 802.11n but its capabilities have been extended in 802.11ac.
802.11ac supports a mandatory 80 MHz channel bandwidth for stations (vs. 40 MHz maximum in 802.11n), 160 MHz available optionally and more (up to 8) special
streams.
A single antenna and 80 MHz channel bandwidth provides a bandwidth of 433Mbps. In this question, we need a minimum bandwidth of 800Mbps. Two antennas
and 80 MHz channel bandwidth provides a bandwidth of 867Mbps and therefore meets the requirement.