July 2010 doc.: IEEE 802.11-10/0xxxr0 Revised shorter presentation to TGax relating to coexistence efforts in Coexistence SC 12 Sept 2017 Authors: Name Company Phone email Andrew Myles Cisco +61 418 656587 amyles@cisco.com Andrew Myles, Cisco Andrew Myles, Cisco

Work is required in ETSI BRAN (& maybe 3GPP) is required to ensure 802 Work is required in ETSI BRAN (& maybe 3GPP) is required to ensure 802.11 achieves its potential Situation Problem Solution IEEE 802 has been working with 3GPP on Wi-Fi/LAA coexistence for the last few years … … but IEEE 802 has probably achieved as much as is possible for the moment … although there may be a possibility for IEEE 802 to reengage with 3GPP in the future In parallel, ETSI BRAN has been defining EN 301 893, which will impact coexistence with Wi-Fi globally … … but the current version of EN 301 893 is problematic for 802.11ax performance & spatial reuse … although the planned revision of EN 301 893 provides an opportunity to better enable 802.11ax features Call to action: please actively participate in the Coexistence SC to ensure 802.11ax can achieve its potential! Andrew Myles, Cisco

IEEE 802 has been working with 3GPP on Wi-Fi/LAA coexistence for the last few years … IEEE 802 has been collaborating with 3GPP for the last few years, with a goal of good coexistence between Wi-Fi & LAA (and its variants) There is now some consensus in the Coexistence SC that the collaboration has probably gone as far as it can at this time … …with many points of agreement leading to good LAA refinements … but a few remaining points of disagreement The main open issues, as documented in the last two Liaison Statements from IEEE 802 to 3GPP, are: What are appropriate PD/ED thresholds? Should a device be allowed to transmit energy for primary purpose of blocking the transmissions of other devices? Should LAA implementations be subject to mandatory testing to validate claims made about LAA/Wi-Fi coexistence? The move of LTE into unlicensed spectrum requires coordination for continued “fair” & “efficient” access IEEE 802 has been working with 3GPP on these issues since 2014 and has been partially successful The IEEE 802.11 Coexistence SC has now decided to pivot to focus mainly on ETSI BRAN rather than 3GPP, using EN 301 893 to: Allow any technology to use 802.11’s dual threshold option Enable innovation based on spatial reuse Restrict the inappropriate use of blocking energy Call to action: please participate in the Coexistence SC’s work if you are interested in coexistence issues! … but IEEE 802 has probably achieved as much as is possible for the moment Andrew Myles, Cisco

In parallel, ETSI BRAN has been defining EN 301 893, which will impact coexistence with Wi-Fi globally For the last two years, ETSI BRAN has been revising the EN 301 893 Harmonised Standard to align it with the RE-Directive in Europe, particularly Article 3.2: Radio equipment shall be so constructed that it both effectively uses and supports the efficient use of radio spectrum in order to avoid harmful interference The latest version of EN 301 893 is now in operation, and enforces coexistence between multiple technologies by defining: LBT similar to EDCA … … and TxOPs similar to EDCA … with an ED-only mechanism … or a PD/ED-mechanism as defined by the IEEE 802.11 standard The impact of EN 301 893 is not just limited to Europe, with many countries adopting the European rules Andrew Myles, Cisco

The current version of EN 301 893 is problematic for 802 The current version of EN 301 893 is problematic for 802.11ax performance & spatial reuse The current version of EN 301 893 will probably result in good coexistence between 802.11ac and LAA However, EN 301 893 has some potential serious problems in the context of 802.11ax Some people believe EN 301 893’s PD/ED requirements mean that 802.11ax will have less performance than 802.11ac (& LAA) 802.11ax is required to use an ED of -72 dBm (roughly) Whereas 802.11ac can use an ED of -62 dBm EN 301 893’s PD/ED requirements mean that 802.11ax will be unable to use its new colour based spatial reuse mechanism There are no exceptions to the rule for a PD of -82 dBm Andrew Myles, Cisco

The upcoming revision of EN 301 893 provides an opportunity to better enable 802.11ax features ETSI BRAN has just adopted a WI to revise EN 301 893, with anything related to Article 3.2 of the RE-Directive within scope The revision provides 802 with an excellent opportunity to propose refinements to make EN 301 893 more compatible with 802.11ax features … and established 802 positions 802.11 WG has already asked ETSI BRAN to allow 802.11ax to use the same ED/PD mechanisms as 802.11ac, thus solving the performance issue Coex SC has started discussing ways to enable spatial re-use without diminishing the “fair” coexistence enforced by EN 301 893 802.11 WG could ask ETSI BRAN to enforce restrictions on the transmission of energy with a primary purpose of blocking others from transmitting Alternatively, IEEE 802 could ask ETSI BRAN to significantly loosen the requirements in EN 301 893, with a bias to enabling innovation rather than ensuring coexistence This approach is preferred by some Coex SC participants Andrew Myles, Cisco

Call to action: please participate in Coexistence SC to ensure 802 Call to action: please participate in Coexistence SC to ensure 802.11ax can achieve its potential Please participate in Coexistence SC if you are … Interested in promoting “fair” coexistence with Wi-Fi (particularly 802.11ax) in a multi-technology environment Interested in engaging with ETSI BRAN on EN 301 893, to either: Refine the rules to enable 802.11ax features, with a “fair” coexistence bias Loosen the rules to enable 802.11ax features, with an innovation bias Interested in any re-engagement with 3GPP on coexistence issues eg for LAA, eLAA, feLAA, NR Interested in engagement with other organisations on coexistence issues eg MulteFire Alliance If IEEE 802 does not address these issues there is a risk 802.11ax will not achieve its potential as the basis of the next generation of Wi-Fi Andrew Myles, Cisco