802.11ac Is Here, but the Second Wave Is Worth Waiting For

Mobile Development Trends for 2014

The IEEE’s family of 802.11 wireless protocols has been one of the technical success stories of the past decade. It tends to get lost in the shadow of the cellular technology. But Wi-Fi is a winner, and the ecosystem keeps adding to its success.

The latest hot spec in the 802.11 family is 802.11ac, which was officially promulgated last month. ABI Research suggests that the rise actually will be rather remarkable:

Sales of 802.11ac Wi-Fi access points only accounted for 8 percent of the total market in 2013 but ABI Research says that figure should hit 45 percent by the end of this year.

GigaOm’s Kevin Tofel suggests that the faster uptake of 802.11ac Wi-Fi will be at least partially due to the increased comfort level of vendors as the standard hardens. Tofel says that relatively few devices currently support the standard. Presumably, that will need to change if the 45 percent mark is to be reached.

The importance of 802.11ac also was noted in IDC’s quarterly report on WLAN sales, which was released last week. The firm didn’t break out the variations, but did refer to the influence of 802.11ac and said that it is one of the drivers of the category. Overall, IDC found that the wireless category (enterprise and consumer combined) grew 11.5 percent in the fourth quarter compared to the fourth quarter of 2012.

It is important to note that 802.11ac is not a monolithic category. At Network Computing, Lisa Phifer describes the two 802.11ac waves. The first consisted of 262 products that passed Wi-Fi Alliance tests from July through the end of last year. Phifer describes the characteristics of those products and then goes on to focus on what the industry should expect with the second wave. Both Phifer and Julie Knudson, writing for Enterprise Networking Planet, suggest that businesses are more interested in the second wave.

The biggest innovation in wave 2 is the inclusion of multiple user multiple in/multiple out (MU MIMO) antennas. The technology has the potential to have a tremendous impact. Phifer says:

MU-MIMO is a novel technology that might double or even quadruple WLAN user density by increasing the number of simultaneously supported clients. Wave 2 APs with MU-MIMO may use up to 8×8 antennas and transmit/receive streams, conversing with clients that support between one and four streams. This mismatch is intentional; MU-MIMO lets APs leverage beamforming to not only serve one user better, but to serve multiple users at once. For example, a Wave 2 AP might communicate with four single-stream smartphones on the same channel, or with two 4×4 notebooks.

Knudson discussed wave 2 with Christian Gilby, director of product and solutions marketing at Aruba Networks, who also stressed the importance of MU-MIMO:

Many enterprises are hankering for the second wave of 802.11ac, which Gilby said will probably start Wi-Fi Alliance certification in late 2015. Perhaps most significant is the anticipated release of multi-user MIMO for the downstream direction, an improvement that will give a switch-like experience to APs with transmission to multiple clients simultaneously. ‘I could send two spatial streams to one client, one spatial stream to another,’ Gilby explained. Wave 2 of the standard is also expected to bump from 3 spatial streams to 4, giving another 33 percent speed improvement.

Business should follow 802.11ac closely, but have no reason to jump into it too quickly, however, unless the need to upgrade from the previous version is overwhelming. It certainly appears that holding out until the second wave hits next year is the optimal solution for most.