802.11ac - the new 5th Generation IEEE standard for Gigabit WiFi
This is a unique, high-value training course covering existing 820.11abgn Wi-Fi networks - plus the emerging IEEE 802.11ad Wi-Fi WLAN standard, technologies, PHYsical and MAC layers in depth.
IEEE 802.11ac is the new draft standard for Gigabit WiFi.
802.11ac promises data rates of up to 1.73Gbps between an access point and a wireless client.
The terminology used by the 802.11ac Working Group - "Very High Throughput (VHT) for lower 6GHz band" - essentially means "data rates higher than those of 802.11n" .. "working in the 5GHz band".
The IEEE Task Group for 802.11ac (IEEE 802.11 TGac) published its first draft of 802.11ac on 20 January 2011 - the Initial Technical Specification Draft 0.1. The 802.11ac standard will support data rates of around 1Gbps by using advanced features over and above 802.11n, including:
It is important to note that 802.11ac will NOT work in the 2.4GHz band, since there is insufficient spectrum there for the 80MHz and 160MHz channel widths that 802.11ac will use.
LEVER whole-heartedly welcomes that fact that this, and another new WiFi standard, will finally abandon the 2.4GHz spectrum!
Why? - Contact us to find out!
802.11ac is now being termed by some as "5G WiFi - the 5th generation of Wi-Fi".
Actually, it's the 5th generation of 802.11 - which isn't the same as Wi-Fi - but it's likely that the term fifth generation WiFi will stick.
Another reason for the term 5G WiFi - somewhat obvious - is that 802.11ac will only work in the 5GHz frequency band.
IEEE 802.11ac will be the world's fastest and most reliable Wi-Fi standard for consumers and enterprises, designed to meet the explosive growth in content consumption, and the proliferation of wireless devices. Some of the golas of 802.11ac include improved link reliability, faster throughput, higher capacity, broader coverage and longer battery life.
802.11ac will be the first standard to introduce Multi-User MIMO - MU-MIMO. 802.11ac with MU-MIMO will allow simultaneous MIMO transmissions to different users - but using a single channel.
So, theoretically, an 8-antenna access point working with four two-antenna client stations - all sharing a 160MHz channel, could burst data at 1.73 Gbps to each station. That is - a burst rate of 6.93 Gbps!
We must always realise, however, that in order to achieve these higher throughput figures, you will need the highest specification 802.11ac client and AP equipment.
Moreover, you must in no way expect to achieve these 802.11ac data rates - which are actually maximum instantaneous transmit speeds - as real-world 802.11ac throughputs.
Why? - Because of the usual 802.11 overheads: frame headers, Preambles, Inter-Frame Spaces (quiet periods), Control Frames .. lower-bit-rate clients contending for the same channel; co-channel interference (mutual interference) - especially in WiFi networks that are not expertly designed .. .. and much more.
802.11ac speed enhancements and MU-MIMO are nonetheless key technologies for high-capacity WiFi wireless networks. For example, 802.11ac operating at 1Gbps should allow simultaneous streaming of three lightly-compressed HDTV channels.
In LEVER's view however, the users who stand to benefit the most from 802.11ac will be Enterprise Wi-Fi networks with medium-to-high user densities. This includes Universities, Colleges, Schools - in fact many situations where existing user applications currently only work well over switched/wired 100/1000 Mbps Ethernet networks.
Update - February 2013:
LEVER performed some throughput testing with a SOHO-grade Asus RT-AC66U 802.11n/802.11ac router. We achieved 125 Mbps of actual throughput - disk-to-disk (after TCP/IP headers were stripped) - to a single client laptop, using a Netgear A6200 dual-stream 802.11ac USB 2.0 adapter. We were reasonably impressed!
This level of performance was achieved at the 802.11ac 866 Mbps associated data rate (using an 80 MHz channel and 2x spatial streams).
Those throughput tests, however, were limited by the throughput capabilities of the FTP server, since wired (Gigabit Ethernet) speeds weren't much faster ..
So we ran some optimised Iperf/Jperf tests .. and achieved one-way 802.11ac throughputs of up to 390 Mbps under the same conditions. This IS impressive!
We expect to achieve even higher throughput between two 3x3 MINO 802.11ac APs or 802.11ac wireless bridges - in the order of 200Mbps real-world throughput at Layer 7.
Whereas 802.11n introduced different, optional methods for beamforming, IEEE 802.11ac also introduces a single, standardised method. This will increase the chances of beamforming being used by 802.11ac devices
Beamforming is the technique of using multiple RF chains and antennas to create a directional multi-element antenna. This allows the RF enegry in frame transmissions to be directed towards the intended recipient, and away from other users.
Beamforming can both increase signal strength at the reciever - hence increase the range of operation; and also increase Signal to Noise Ratio (SNR) - for both the intended receiver, and also for other devices in the area (since they receive less of what would be regarded as an interfering signal).
According to PCWorld, Netgear is officially the first networking company with an 802.11ac Wi-Fi router, the company announced Thursday 26 April 2012. The R6300, which will debut in May, will reportedly run up to 1.3Gbps, which makes it (theoretically) more than four times as fast as current 2x2 MIMO 802.11n routers.
Finalisation of the 802.11ac standard is anticipated late 2012, but final IEEE 802.11 Working Group approval of 802.11ac is not expected until late 2013. This is according to the official IEEE 802.11 Working Group Project Timelines.
Enterprise-grade 802.11ac WiFi equipment is expected to become available late 2012 / early 2013 and to proliferate thereafter, with a potential 1 billion devices shipping in 2015, according to In-Stat.
However, as with 802.11n products, do not expect early-release devices to support 8x8 MIMO.
The DG News Service has announced that Smartphones and tablets with 802.11ac will arrive early in the second half of 2013 - according to a Qualcomm executive. Mobile devices based on Qualcomm's Snapdragon 800 series processors will be the company's first to get 802.11ac Wi-Fi.
Qualcomm's competitor Broadcom has said it hopes to put 802.11ac wireless networking in mobile devices early this year.
A frequently-asked question is: Should I wait for 802.11ac products to become available from the major vendors?
Whether to deploy 802.11ac depends on a range of factors. It's important to realise that at present, any 802.11ac product will be 802.11ac draft compliant. 802.11ac ratification and 802.11ac certification by the Wi-Fi Alliance will not happen until 2013.
In particular, MU-MIMO will not feature in Enterprise 802.11ac products until 2014.
It really is important understand the capabilities of different vendors' 802.11ac equipment - it certainly isn't all equal.
Contact us for vendor-neutral advice on what we expect the WLAN vendors to be doing with 802.11ac - Cisco, Aruba, Ruckus, Juniper, Meru, HP, Aerohive, Motorola, Xirrus, Ubiquiti and more.
PS: If you're interested in a vendor that isn't listed above - there's a reason. Contact us to find out more.
Meanwhile, there's the IEEE 802.11ad standard - for Very High Throughput in 60GHz spectrum (milli-metre wavelengths). 802.11ad will operate at instantaneous burst speeds of up to 7Gbps.
The IEEE 802.11ad Working Group have also now aligned with the Wireless Gigabit Alliance (WiGig). The resulting 60GHz wireless technogies will offer even higher data rates than 802.11ac, but only at relatively short distances - and where walls, ceilings and other obstructions don't appear in the path. 802.11ad and WiGig will therefore be more suitable for cable-replacement applications.
The primary benefit of operating at 60GHz is that there are hundreds of megahertz of spectrum available.
LEVER are industry-leading WiFi consultants, delivering independent and authoritative advice on WiFi Planning and Design; wireless Site Survey, wireless network troubleshooting, analysis and optimisation and much more.
Our skills in wireless network Survey, Analysis, Diagnosis and Remdiation are unrivalled.
Contact LEVER now for free, independent advice on all aspect of WiFi deployment and WiFi standards - not just 802.11ac!