802.11ac Primer – How is it different from 802.11n?
802.11ac Wave-2 features include: (Note this paper concentrates on Wave-1) as Wave-2 is still in flux.
•Everything supported in Wave-1
•Multi-user MIMO <Multiple Input Multiple Output> client enhancement
•Bonding up to 160 MHz
•Faster Ethernet uplinks exceeding GbE
Figure 61 1 Spatial Stream MCS rates for 801.11n (left) and 1 Spatial Stream MCS rates for 802.11ac
Figure 62 Channel bonding allows more usable bandwidth (similar to a multi-lane highway)
So the net take-away is that 802.11ac permits faster speeds – allowing clients to take advantage of the additional bandwidth and complex modulation for over-all performance enhancement while maintaining backward compatibility with 802.11n and 802.11a/g systems already in place.
Cisco Aironet Series 1600/2600/3600 Access Point Deployment Guide, Release 7.5
