Wi-Fi Alliance assures coexistence test plan on track for Sept. 21 delivery

Despite naysayers who questioned whether a plan would be ready this month, the Wi-Fi Alliance (WFA) reassured attendees at last week’s CTIA Super Mobility 2016 trade show that, indeed, the coexistence Wi-Fi/LTE-U testing plan it’s been developing is expected to be delivered as planned on September 21.

The reassurance from the WFA is noteworthy because some members of the LTE community, many of whom were in high attendance at CTIA, publicly expressed doubt that the plan would actually be ready in September, citing earlier deadlines misses. Supporters of the alliance pointed out, however, that the only real missed date was moving completion of the plan from August to September.

Things are progressing well, and the validation effort that was happening in the lab over the past two weeks is effectively done, WFA Director of Marketing Kevin Robinson told FierceWirelessTech. A coexistence test workshop is scheduled for September 20 in San Jose, California, to provide attendees the opportunity to review the test plan status, hear an update from the plugfest and review the updated test plan delivery schedule.

WFA is aware of recent critical comments that some, including the likes of Verizon and Qualcomm, have made about the test plan, but Robinson said stakeholders are still involved and active in the process, including in the labs.

“All the various stakeholders – there are aspects of this project that they’re not particularly happy with,” he said. “It has been a compromise, but what Wi-Fi Alliance is very encouraged by is that after the last workshop and going into the plugfest that we’ve just concluded, all of those stakeholders have still been very much committed to getting the work done. They are still very much invested in the effort.”

After September 21, when the test plan will be complete, there will be at least one lab capable of executing the testing, and what happens from that point on in terms of the remaining steps for commercialization are really up to service providers and their equipment vendors. Two third-party test laboratories, Cetecom and AT4, will offer coexistence test services.

One of the areas of particularly contentious discussion has been around what they term Level 3, or -82 dBm. Those in the Wi-Fi community say that -82 dBm level is important while others suggested a lower level be included in the test plan. From the Wi-Fi industry perspective, that level is important because it really reflects many of the usage scenarios for Wi-Fi, such as outdoor networks. Wi-Fi operates very well at that the -82 dBm level; it’s what is currently in the test plan and for outdoor deployments, there’s pretty broad consensus that that is the right number for those scenarios, he said.

Others have pointed out that using a measurement of -82 dBm in the Wi-Fi Alliance test plan is an extraordinary compromise on the part of Wi-Fi proponents because it would mean that the test plan leaves half of all outdoor Wi-Fi connections vulnerable to LTE-U degradation. Robinson said Wi-Fi has operated very well for years in unlicensed spectrum, but the WFA going into this knew they could not cover every single scenario and it’s worth noting it’s exactly that: Unlicensed spectrum, where even though Wi-Fi is designed to be polite, there’s no guarantee as the spectrum must be shared.

“It was really about getting the appropriate balance of maintaining the experience for large numbers of devices, but getting to a place where you can have industry to agree to that testing,” he explained. “If the testing doesn’t happen … it almost doesn’t matter. You can take a position that ultimately leads to devices not being tested and a worse experience for Wi-Fi users. Wi-Fi Alliance feels like we’re delivering a reasonable compromise that will generally ensure that our goals of fairness are met.”

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