802.11ax has taken longer than previous standards to ratify
SAN JOSE, Calif. — July 1 is the big day for 802.11ax, the next big thing in Wi-Fi. That’s the date engineers are expected to approve an initial draft of the standard.
It’s been a longer than anticipated road to get to this point. First and second drafts failed to get the required 75% approval from the group in November 2016 and September 2017. At one point pundits thought early 11ax products might ship in 2017.
Typically, IEEE standards take three years. The 11ax group has been at it four years so far. That’s longer than today’s 11ac standard took, but still shorter than the complex 11n standard before it.
Participants blame the complexity of the spec. It aims to boost users’ data rates up to 30 percent while lowering latency nearly 4x and delivering as much as four times the overall data on the same spectrum as today’s 11ac.
To do so, its adds to Wi-Fi OFDMA modulation, a spectrum efficiency technique already used in cellular networks. It also expands support for multi-user MIMO antennas and adds 1,024 QAM.
Given the delay, one market researcher this week slashed its forecast for enterprise-class 11ax access points from 750,000 standard units this year to 250,000, mainly lower cost, pre-standard units. That shaved about $500 million off Dell’Oro Group’s projections for all enterprise-class access points, now expected to generate revenues of $5 billion this year.
“During out interviews, we discovered a number of key enterprise-class system makers are delaying 11ax rollouts from Q2 to Q4 2018 or Q1 2019,” said Trent Dell’Oro, a business analyst for Dell’Oro Group, pointing to the 11ax group’s failure to gain a 75% consensus on the September 2017 draft standard.
The 11ac standard will continue to represent the “vast majority” of business in Wi-Fi access points shipped this year, he said. But he noted OEMs such as Huawei and H3C, a spinout of Hewlett-Packard’s operations in China, have aggressive plans to be first in the market with 11ax products.
Intel, Qualcomm and others have been sampling pre-standard 11ax chips for nearly 18 months. Qualcomm notes Japan’s KDDI already advertises 11ax access points made by NEC using its IPQ8078 chip. Huawei also said it will use the chip in systems it will make.
“There was a very optimistic view of how quickly we could move through the standards and certification process in the beginning, but if you gave everyone a dose of truth serum…” you might have heard other views, said Jesse Burke, a connectivity product marketing manager at Qualcomm.
Burke characterized the Dell’Oro projections as the result of “a narrative being asserted from some customers that plan a relatively slow rollout of 11ax, and favor 11ac because it aligns with their product readiness.”
Wi-Fi Alliance now conducting interop tests
Leaders of the 802.11ax group expressed confidence the latest draft of a working group standard will get the required 75% approval. The physical layer part of the spec, a key for making chips, has been stable for some time and most changes have been related to the media access controller and could be addressed in software, they said.
The lack of consensus on the 2016 and 2017 drafts “reflects the complexity of the standard,” said Robert Stacey, technical editor of 11ax.
“Some people vote no if they feel the draft is incomplete. We added a lot of features, so there was a lot of potential for problems, and if there is one problem people tend to vote no,” said Stacey, a principal engineer for Intel who also served as editor for 11ac.
“I’m pretty confident we’ll get the 75% vote now. We’ve spent quite a bit of time fixing all the problems, and there were not many technical changes from the 2.0 to the 3.0 drafts. I think we have stopped adding features and moved to bug fixes,” he said.
The Wi-Fi Alliance (WFA) still needs to complete its certification program for 11ax, something it is expected to have in place by fall 2019. It has started work conducting interoperability tests using pre-standard chips.
The group recently voted to make WPA 3, the latest version of its security software, a mandatory part of its 11ax certification. “We fought hard for that decision because we are making WPA 3 a standard across our Wi-Fi portfolio…it’s a differentiator for us,” said Burke of Qualcomm.
If all goes well, a final 11ax standard will be published in December 2019. By then, WFA-certified products will be shipping in volume.
— Rick Merritt, Silicon Valley Bureau Chief, EE Times