The 802.11 wireless network standard has come a long way since the first base version was introduced in 1997. Over the past 20 years, the Institute of Electrical and Electronics Engineers (IEEE) has developed a dozen different versions of the protocol, each designed to solve various problems and meet ever-increasing Wi-Fi demands.
Much of the emphasis has been on performance. While early versions of the standard offered just 1Mbps of throughput, the latest 802.11ac Wave 2 technology boasts a maximum speed of up to 6.77Gbps. 802.11ac Wave 2 is also able to support much greater device density, which has become critical as user demands have intensified.
802.11ac Wave 2 employs several techniques to achieve this level of performance. One is multiuser multiple input, multiple output (MU-MIMO), which provides for eight data streams over the same frequency channel, with up to four user transmissions per stream. Another is beamforming, which transmits radio waves in a specific direction, even around obstacles, to increase the effective range. In addition, 802.11ac Wave 2 gets a performance boost through 160MHz channels, a faster data rate and the use of the 5GHz spectrum.
Products based on the 802.11ac Wave 2 standard started hitting the market last year, and are seeing rapid uptake. However, next-generation technology is already on the horizon that promises to take Wi-Fi even further.
802.11ax combines MU-MIMO with orthogonal frequency division multiplexing (ODMF), which subdivides each channel into hundreds of sub-channels that are turned at right angles and stacked on top of each other. With traditional Wi-Fi technology, a data transmission must end before the next one begins. ODMF makes it possible for devices to share each channel without taking turns, increasing data throughput to about 10Gbps and supporting even greater numbers of users.
One of the biggest advances in 802.11ax is the ability to address the ever-growing problem of Wi-Fi overcrowding, where so many APs are broadcasting on the same channel that it becomes almost unusable in high-density areas. The 802.11ax spec calls for “color-coding” traffic so the AP and client can filter out traffic that is not part of that that code.
The new 802.11ax standard will also include a feature called “wake time scheduling,” which will enable access points to provide devices with a schedule of when they can go to sleep. Although the sleep times are short, they will make a big difference in terms of device battery life.
Several vendors have already released chips based on 802.11ax. However, the standard won’t be finalized until 2018, and business-class products won’t hit the market until late next year. Pre-standard products will likely be introduced for the consumer market first, which gives vendors a chance to work out any kinks before offering solutions for enterprise networks.
A lack of compatible devices will also slow 802.11ax adoption. Today, very few smartphones, tablets or laptops are compatible with 802.11ac Wave 2. It will be 2019 or even 2020 before the first 802.11ax-compliant devices are introduced.
Still, organizations should keep Wi-Fi developments on their radar as they plan for network upgrades. SageNet’s experts can assess your existing infrastructure and capacity demands, and help you develop a wireless networking strategy that will best support your business and IT requirements.
In a future post, we’ll look at some of the other standards that have emerged to support the Internet of Things and other wireless use cases.