Wi-Fi Alliance releases draft test procedures for Wi-Fi/LTE-U coexistence

While the Wi-Fi Alliance (WFA) is facilitating the development of a coexistence test regimen to make sure LTE-U devices play fair with Wi-Fi, a group of companies – including Google (NASDAQ: GOOG) and Microsoft (NASDAQ: MSFT) – wants to make it crystal clear that much more collaboration and technical work needs to be done before it reaches a final stage.

The WFA held its second major workshop on coexistence Wednesday in San Jose, Calif., and released a draft test plan for Wi-Fi and LTE-U co-existence on its website. But it emphasized in a statement after the workshop that it's impossible to draw firm conclusions about device coexistence until validation of the entire test plan is complete.

In a statement, the alliance said that since the last workshop, Wi-Fi Alliance members have made significant progress on the test regimen, which resulted in the draft test plan. "We reached consensus on a number of points, including agreement that the established approach to test development is working, the test plan is sufficiently mature to begin a validation exercise, and some specific areas require further research and definition," the alliance said.

"Attendees agreed that ongoing collaboration within Wi-Fi Alliance is essential to resolving remaining industry concerns. Wi-Fi Alliance will continue to facilitate development of the coexistence test regimen and will host a follow-up workshop," the group said.

Meanwhile, a group of companies sent a letter to Wi-Fi Alliance President and CEO Edgar Figueroa saying they continue to support the Wi-Fi Alliance's goal of finding a path to protecting consumers from interference while emphasizing that the draft is a work in progress rather than a final plan for adequate testing. Besides Google and Microsoft, the companies or entities signing the letter include Aruba Networks, Boingo Wireless, Broadcom, CableLabs, Cablevision Systems Corp., Comcast (NASDAQ: CMCSA) and Ruckus Wireless.

"It is important that the industry develop specific pass and fail metrics calibrated to ensure that LTE-U devices do not disproportionately degrade Wi-Fi performance across a range of realistic testing scenarios," the letter to Figueroa states. "We believe that the Draft Test Procedures are generally on a good trajectory in this regard, and we strongly urge that this rigorous approach continue to be strengthened as the test plan is further developed."

While both the Wi-Fi Alliance and the cable companies are signaling a need for more collaboration, their progress reports are important given the FCC's interest in LTE-U. The FCC started a proceeding on LTE-U and LAA last year after complaints surfaced that the LTE-U advocates were intent on introducing LTE in unlicensed spectrum, threatening to interfere with Wi-Fi users in that spectrum, charges that the LTE-U advocates have vehemently denied. A lot of the companies that support LTE-U, including Qualcomm (NASDAQ:QCOM) and Verizon (NYSE: VZ), also offer products or services that rely on properly working Wi-Fi.

Qualcomm said in a statement that it is pleased to be working with the Wi-Fi Alliance to stabilize the coexistence test plan so that validation testing can begin. "The detailed test plan is the result of extensive technical collaboration between WFA and LTE-U Forum members," said Mingxi Fan, vice president of engineering at Qualcomm Technologies. "Indeed, as a member of the Wi-Fi Alliance and of the LTE-U Forum, Qualcomm wants to ensure that LTE-U and Wi-Fi coexist very well. This outcome is in our best interest given our substantial Wi-Fi business. We look forward to continued collaboration with all stakeholders as the test plan is finalized."

Bill Maguire, executive director of WifiForward's Save our Wi-Fi campaign, said the Wi-Fi Alliance announcement of the development of an initial testing plan for evaluating Wi-Fi/LTE-U coexistence is an important first step for ensuring that access to the Internet is not disrupted for millions of Wi-Fi users and other users of unlicensed spectrum. WifiForward partners include Broadcom, Comcast, Public Knowledge, Microsoft, Ruckus and others.

"Many stakeholders have raised serious and widespread concerns about the likely harm LTE-U will cause to Wi-Fi," he said in a statement. "We understand that more work needs to be done to ensure coexistence between Wi-Fi and LTE-U and we are hopeful that the WFA testing methodology still under development will address all of those concerns. Wi-Fi and unlicensed spectrum are an engine of innovation for the United States, generating over $222 billion for the U.S. economy every year and the businesses, communities and consumers who depend on it every day must be protected."

For more:
- download the letter to the Wi-Fi Alliance here
- see the Wi-Fi Alliance site
- see this WifiForward blog

Related articles:
Wi-Fi Alliance: Work on LTE-U testing regime ongoing, but it's unclear when it will be finished
Wi-Fi Alliance presents coexistence guidelines; LTE-Forum revises specs to ensure LTE-U coexistence with Wi-Fi
Wi-Fi Alliance pushes ahead on coexistence guidelines for LTE-U
LTE, Wi-Fi delegates collaborate, not clash, during coexistence workshop in Beijing

Article updated Feb. 11 to include comment from Qualcomm.