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Agenda for IEEE 802.11 Coexistence SC meeting in Berlin in July 2017

Welcome to the first face-to-face meeting of the Coexistence SC in Berlin. This meeting will discuss issues related to the 3GPP RAN1 request to adopt an ED of -72dBm. We will also review official IEEE-SA patent material.

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Agenda for IEEE 802.11 Coexistence SC meeting in Berlin in July 2017

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  1. Agenda for IEEE 802.11 Coexistence SC meetingin Berlin in July 2017 • 12 July 2017 Authors: Andrew Myles, Cisco

  2. Welcome to the first F2F meeting of the Coexistence SC in Berlin in July 2017 • The IEEE 802.11 PDED ad hoc was formed in September 2016 at the Warsaw interim meeting • PDED stands for Preamble Detect Energy Detect • PDED is an attempt to encapsulate the goal of the group … • … which is to discuss issues related to the 3GPP RAN1 request to IEEE 802.11 WG to adopt an ED of -72dBm • Andrew Myles was appointed as Chair • The IEEE 802.11 PDED ad hoc met in San Antonio (Nov 2016), Atlanta (Jan 2017), Vancouver (Mar 2017) and Daejeon (May 2017) • In Daejeon in May 2017 it was decided to convert the IEEE 802.11 PDED ad hoc into the IEEE 802.11 Coexistence SC • The IEEE 802.11 Coexistence SC will meet (for the first time!) on: • Wednesday PM1 • Thursday PM1 Andrew Myles, Cisco

  3. The first task for the Coexistence SC today is to appoint a secretary • It is important to keep proper minutes of all Coexistence SC meetings • However, it is generally not practical to Chair a meeting and take minutes at the same time • Especially without a recording  • Therefore we need a volunteer for a Secretary • At least for this session … • … and thanks to Thomas Derham, Dick Roy, Graham Smith & Guido Hiertz for volunteering previously • The rewards for the Secretary are numerous • Power over the SC • Respect from your peers • … and a cold beverage from the Chair • … although no one has claimed one yet! Andrew Myles, Cisco

  4. The Coexistence SC will review the official IEEE-SA patent material for pre-PAR groups • All IEEE-SA standards meetings shall be conducted in compliance with all applicable laws, including antitrust and competition laws. • Don’t discuss the interpretation, validity, or essentiality of patents/patent claims. • Don’t discuss specific license rates, terms, or conditions. • Relative costs, including licensing costs of essential patent claims, of different technical approaches may be discussed in standards development meetings. • Technical considerations remain primary focus • Don’t discuss or engage in the fixing of product prices, allocation of customers, or division of sales markets. • Don’t discuss the status or substance of ongoing or threatened litigation. • Don’t be silent if inappropriate topics are discussed… do formally object. Andrew Myles, Cisco

  5. The Coexistence SC will review the official IEEE-SA patent material for pre-PAR groups • If you have questions: • Contact the IEEE-SA Standards Board Patent Committee Administrator at patcom@ieee.org • Visit standards.ieee.org/about/sasb/patcom/index.html • See IEEE-SA Standards Board Operations Manual, clause 5.3.10 and “Promoting Competition and Innovation: What You Need to Know about the IEEE Standards Association's Antitrust and Competition Policy” for more details. • This slide set is available at: • development.standards.ieee.org/myproject/Public/mytools/mob/slideset.ppt Andrew Myles, Cisco

  6. Links are available to a variety of other useful resources • Link to IEEE Disclosure of Affiliation • http://standards.ieee.org/faqs/affiliationFAQ.html • Links to IEEE Antitrust Guidelines • http://standards.ieee.org/resources/antitrust-guidelines.pdf • Link to IEEE Code of Ethics • http://www.ieee.org/web/membership/ethics/code_ethics.html • Link to IEEE Patent Policy • http://standards.ieee.org/board/pat/pat-slideset.ppt Andrew Myles, Cisco

  7. The Coexistence SC hoc will operate using accepted principles of meeting etiquette • IEEE 802 is a world-wide professional technical organization • Meetings shall be conducted in an orderly and professional manner in accordance with the policies and procedures governed by the organization • Individuals shall address the “technical” content of the subject under consideration and refrain from making “personal” comments to or about others Andrew Myles, Cisco

  8. The Coexistence SC will review the modified “Participation in IEEE 802 Meetings” slide • Participation in any IEEE 802 meeting (Sponsor, Sponsor subgroup, Working Group, Working Group subgroup, etc.) is on an individual basis • Participants in the IEEE standards development individual process shall act based on their qualifications and experience (IEEE-SA By-Laws section 5.2.1) • IEEE 802 Working Group membership is by individual; “Working Group members shall participate in the consensus process in a manner consistent with their professional expert opinion as individuals, and not as organizational representatives”. (sub-clause 4.2.1 “Establishment”, of the IEEE 802 LMSC Working Group Policies and Procedures) • Participants have an obligation to act and vote as an individual and not under the direction of any other individual or group. A Participant’s obligation to act and vote as an individual applies in all cases, regardless of any external commitments, agreements, contracts, or orders • Participants shall not direct the actions or votes of any other member of an IEEE 802 Working Group or retaliate against any other member for their actions or votes within IEEE 802 Working Group meetings, (IEEE-SA By-Laws section 5.2.1.3 and the IEEE 802 LMSC Working Group Policies and Procedures, subclause 3.4.1 “Chair”, list item x) • By participating in IEEE 802 meetings, you accept these requirements. If you do not agree to these policies then you shall not participate Dorothy Stanley, HP Enterprise

  9. The Coexistence SC will consider a proposed agenda • Proposed Agenda • Bureaucratic stuff, including approving minutes • Why was the PDED ad hoc formed … and why is it now the Coexistence SC? • What is happening this week? (in no particular order) • Review the response from 3GPP RAN1/RAN4 on the PDED issue • Review the status of the LS to 3GPP RAN4 on the PDED issue • Review the response from 3GPP RAN on the PDED issue • Review the status of ETSI BRAN relating to the revision of EN 301 893 • Review the response from 3GPP RAN1 on non-PDED issues • Discuss the coexistence activity with 802.11 TGax? • What are the next steps? • Other business • Any objections to this agenda? Andrew Myles, Cisco

  10. The Coexistence SC will consider approval of the PDED ad hoc meeting minutes from Daejeon • Guido Hiertz (Ericsson) kindly took notes for the PDED ad hoc at the Daejeon meeting in May 2017 • The notes are available on Mentor: • Tue EVE: 11-17-0815-00 • Wed PM1: 11-17-823-00 • Thu PM1: 11-17-834-00 • Are there any objections to approval of these notes as the minutes of the meeting by consent? Andrew Myles, Cisco

  11. Why was the PDED ad hoc formed … … and why is it now the Coexistence SC? Andrew Myles, Cisco

  12. A number of liaisons between IEEE 802 and 3GPP left the PDED issue open as of September 2016 Mar 2016 Mar 2016: IEEE 802 requested (19-16-0037-09 ) that 3GPP RAN1 make LAA more sensitive to 802.11 transmissions, using either PD/ED similar to IEEE 802.11ac or ED of -77dBm Jun 2016 3GPP RAN1 rejected (R1-166040) IEEE 802’s request on the basis that they had considerable debate and decided there was not a problem with an ED of -72dBm; they also requested that IEEE 802.11ax adopt the same mechanism Aug 2016 IEEE 802 noted (IEEE 802 liaison to 3GPP RAN) 3GPP RAN1’s simulations (issue 3) were based on invalid assumptions & asked them to use more realistic assumptions; but did not respond to request that 802.11ax adopt an ED of -72dBm Sept 2016 PDED issue open Andrew Myles, Cisco

  13. PDED ad hoc was formed in Sept 2016 to respond to RAN1 request that 802.11ax adopt an ED of -72dBm • Formation docs from Sept 2016 • 19-16-0110-00 described the PDED issue for IEEE 802.19 WG and a variety of possible responses • 11-16-1263-00 summarised the PDED issue for the IEEE 802.11 WG and this directly led to the PDED ad hoc formation Andrew Myles, Cisco

  14. The charter of the PDED ad hoc was refined over time to deal with issues beyond the liaison with RAN1 PDED ad hoc charter (as updated in Jan 2017) • Address replies from 3GPP RAN1 • Develop further data (based on simulation and testing?) for future LS’s • Address the question of ED threshold in next revision of EN 301 893 that applies to 802.11ax Andrew Myles, Cisco

  15. PDED ad hoc sent LS’s to and received LS’s from 3GPP RAN1 • LS’s to/from 3GPP RAN1 • Nov 2016: PDED ad hoc sent a LS to RAN1 explaining why the RAN1 request that 802.11ax adopt ED = -72dBm does not make sense and requesting RAN1 to adopt PD for LAA • Nov 2016: RAN1 responded with a LS (see issues 13 & 14) that rejected PDED ad hoc’s request to consider use of PD in LAA but did hint there was some possibility of RAN4 testing to resolve disagreements • Mar 2017: PDED ad hoc noted in a LS to RAN1 that there were ongoing disagreements and requested confirmation they could be resolved by RAN4 defined testing Andrew Myles, Cisco

  16. PDED ad hoc also sent LS’s to 3GPP RAN4 and ETSI BRAN • LS’s to 3GPP RAN4 • May 2017: PDED ad hoc sent a LS to RAN4 recommending RAN4 consider an SIR level of 0 dB for their “Below ED” test configuration • LS’s to ETSI BRAN • May 2017: PDED ad hoc sent a LS to ESTI BRAN recommending that the upcoming revision of EN 301 893 should maintain the existing dual threshold option, and extend its applicability to IEEE 802.11ax Andrew Myles, Cisco

  17. In May 2017, it was agreed to transition the PDED ad hoc to the Coexistence SC • In May 2017, the IEEE 802.11 WG Chair noted he was uncomfortable about the PDED ad hoc continuing in that form for a long period • The PDED ad hoc did not agreed to recommend a transition from an ad hoc to a standing committee • The vote failed 7/4/2 (see 11-17-834) • However, the IEEE 802.11 WG agreed to the transition • The vote passed 23/5/7 (see 11-17-739) • Andrew Myles was affirmed as Chair Andrew Myles, Cisco

  18. Coexistence SC scope is focused on ensuring 802.11ax has fair access to global unlicensed spectrum • IEEE 802.11 Coexistence SC scope • Discuss the use of PD, ED or other 802.11 coexistence mechanisms with the goal of promoting “fair” use of unlicensed spectrum • Will initially focus on liaising with 3GPP RAN/RAN1/RAN4 but may also lead to interactions with regulators and other stakeholders • Will probably not conclude at least until RAN4’s 802.11/LAA coexistence testing is defined and successfully executed • May require the SC to consider other simulations and results of tests of potential LAA/802.11 coexistence mechanisms • Promote an environment that allow IEEE 802.11ax “fair access” to global unlicensed spectrum • Will initially focus on encouraging a “technology neutral” solution in the next revision of EN 301 893 that allows IEEE 802.11ax fair access to unlicensed spectrum in Europe(noting the European approach is likely to have global impact) • The effort will also focus on allowing 802.11ax to use innovative mechanisms for frequency reuse without compromising the goal of fair access Andrew Myles, Cisco

  19. Coexistence SC will close when determined by the WG or 802.11ax is ratified • IEEE 802.11 Coexistence SC close down criteria • The SC is closed by the IEEE 802.11 WG • … after it is determined that the SC is unlikely to make further progress towards its goals • IEEE 802.11ax completes Sponsor Ballot • … noting that the PDED ad hoc is unlikely to relevant at that point anyway Andrew Myles, Cisco

  20. What is happening this week? Review the response from 3GPP RAN1 on the PDED issue Andrew Myles, Cisco

  21. 802.11 may need to focus on resolving coexistence issues by working with ETSI BRAN rather than 3GPP • Summary • PDED ad hoc’s March 2017 LS to RAN1 highlighted that the current lack of agreement between IEEE 802 and RAN1 could be resolved with RAN4 testing • However, the RAN1/RAN4 LS response to IEEE 802’s LS suggests that RAN4 defined testing is unlikely to resolve the disagreements • How should IEEE 802 respond to the latest LS from RAN1/RAN4? • It is proposed that IEEE 802 refocus on resolving the issue in ETSI BRAN … and away from 3GPP Andrew Myles, Cisco

  22. PDED ad hoc’s March 2017 LS highlighted the lack of agreement could be resolved with testing • Summary of PDED ad hoc response in March 2017 • IEEE 802 & 3GPP RAN1 have continued to disagree on various issues related to LAA’s ED threshold and its effect on LAA/802.11 coexistence • In the interest of resolving these outstanding issues, IEEE 802 requests that 3GPP continue to work with IEEE 802 to gather additional evidence relating to LAA/802.11 coexistence • IEEE 802 was encouraged by 3GPP’s commitment to gather additional evidence by validating LAA/802.11 coexistence characteristics using test plans developed by 3GPP RAN4 • IEEE 802 is now concerned that 3GPP may not undertake the promised LAA/802.11 coexistence tests before LAA’s deployment • … Andrew Myles, Cisco

  23. PDED ad hoc’sMarch 2017 LS highlighted the lack of agreement could be resolved with testing • Summary of PDED ad hoc response in March 2017 • … • IEEE 802 therefore requests that 3GPP reconfirm its previous commitment to validate LAA/ 802.11 coexistence using tests developed in 3GPP RAN4 before LAA’s deployment • IEEE 802 also requests that 3GPP clarify its plans for other testing of LAA’s channel access mechanisms that may be relevant to LAA/802.11 coexistence • Alternatively, in the absence of availability of timely 3GPP RAN4 testing, IEEE 802 requests 3GPP provide its perspective on extending the Wi-Fi Alliance LTE-U tests to LAA Andrew Myles, Cisco

  24. RAN1/RAN4 response to IEEE 802’s LS suggests that testing is unlikely to resolve disagreements • In May 2017, 3GPP RAN1/RAN4 provided a response to IEEE 802’s March 2017 LS • 3GPP RAN1/RAN4’s response inserts comments after each section of IEEE 802’s LS • The general tone of the commentary seems to confirm IEEE 802’s statement in its LS that: • IEEE 802 & 3GPP RAN1 have continued to disagree on various issues related to LAA’s ED threshold and its effect on LAA/802.11 coexistence • 3GPP RAN1/RAN4’s responseconcludes with a non-specific action requesting that: • IEEE 802 LMSC to take the above into account Andrew Myles, Cisco

  25. IEEE 802’s LS highlighted historical disagreements in clause 1 • PDED ad hoc summary of disagreement in March 2017 (clause 1) • IEEE 802 & 3GPP RAN1 have continued to disagree on various issues related to LAA’s ED threshold and its effect on LAA/ 802.11 coexistence • March 2016: IEEE 802 suggested the use of either an ED threshold of -77 dBm or preambles to enhance LAA/ 802.11 coexistence • May 2016: 3GPP RAN1 rejected IEEE 802’s suggestions for use by LAA of a lower ED threshold or preambles and requested it adopt an ED threshold of -72 dBm for 802.11ax • August 2016: IEEE 802 requested 3GPP RAN1 to change its simulation assumptions to better reflect realistic 802.11 deployments • November 2016: IEEE 802 rejected 3GPP RAN1’s request that 802.11ax use an ED threshold of -72 dBm and requested it consider use of preambles in the Release 14 • November 2016: 3GPP rejected IEEE 802’s request to consider the use of preambles in Release 14 Andrew Myles, Cisco

  26. RAN1/RAN4 are very defensive about the ED-only mechanism in their response to clause 1 • RAN1/RAN4 response in May 2017 (clause 1) – with commentary • RAN1 notes that several members of the IEEE community including several WiFi stakeholders have active representation in RAN1, RAN2 and RAN4 and have provided simulation results to evaluate coexistence between LAA and WiFi. • This text seems to be suggesting the involvement of some Wi-Fi stakeholders means IEEE 802 has less ability to express its perspective in some way • The comment also implies that all of the simulations provided by the Wi-Fi stakeholders support the use of an ED of -72dBm to achieve coexistence between Wi-Fi and LAA • The simulations are not so definitive, with a number of simulations supporting an ED of ~-77dBm for LAA when Wi-Fi is using traditional PD/ED thresholds, especially when considering voice traffic • Some Wi-Fi stakeholders also noted the 3GPP simulation scenarios do not properly represent many typical Wi-Fi scenarios, and doubts were cast on the propagation models Andrew Myles, Cisco

  27. RAN1/RAN4 are very defensive about the ED-only mechanism in their response to clause 1 • RAN1/RAN4 response in May 2017 (clause 1) – with commentary • Such a study was also carried out in ETSI BRAN as well in the development of the EN 301 893 harmonized standard … • Very little study was carried out in ETSI BRAN, with most discussions focusing on reviews of 3GPP simulations • The limited original simulations presented in ETSI BRAN actually called into question the 3GPP simulations, especially for hidden station scenarios and with voice traffic Andrew Myles, Cisco

  28. RAN1/RAN4 are very defensive about the ED-only mechanism in their response to clause 1 • RAN1/RAN4 response in May 2017 (clause 1) – with commentary • …and it was agreed after extensive discussion on multiple occasions that using an ED threshold of -72dBm was the best way forward overall for all recently upcoming systems operating in the 5GHz unlicensed spectrum including LAA … • It was not agreed in ETSI BRAN that ED = -72dBm was the best way forward for all upcoming systems • It was agreed to use ED = -72dBm as a “compromise” solution for LAA to ensure EN 301 893 could be completed in time for the RED deadline, while allowing Wi-Fi to continue using its long used PD/ED parameters • It was also agreed that the mechanism used for 802.11ax (not defined at the time) would be evaluated in the future, when more information was available • … while recognizing that in some scenarios that the choice of a single ED threshold may be sub-optimal. • It is agreed that a single ED threshold may be sub-optimal Andrew Myles, Cisco

  29. RAN1/RAN4 are very defensive about the ED-only mechanism in their response to clause 1 • RAN1/RAN4 response in May 2017 (clause 1) – with commentary • In all the simulations presented, no major coexistence concerns have been identified in both indoor and outdoor scenarios even with the choice of a single ED threshold. • This is not true; IEEE 802 has identified significant concerns by simulations with a single ED threshold being applied to 802.11ax • In particular they show 802.11ax (using ED only) will be disadvantaged compared to both 802.11a/n/ac systems (using PD/ED) and LAA systems (using ED only) • While some companies have suggested using a lower threshold, there has been no consensus based on simulations that a lower threshold is better from an overall system perspective in all scenarios. • The fact that some companies are suggesting the use of a lower threshold implies they believe the ED of -72 dBm is non optimal in some significant way Andrew Myles, Cisco

  30. RAN1/RAN4 are very defensive about the ED-only mechanism in their response to clause 1 • RAN1/RAN4 response in May 2017 (clause 1) – with commentary • RAN1 wishes to highlight that the ED threshold of -72dBm is an upper bound and the eNB either by its own implementation or by using assistance from the UEs can adaptively lower the threshold to better suit the deployed topology and scenario to further improve coexistence. A new measurement configuration for channel occupancy and average RSSI have been defined in Rel-13 LAA to enable such a feature and an eNB, as an implementation choice, can utilize these measurements to adaptively adjust the ED threshold. Furthermore, in Rel-14 LAA where UL transmissions are enabled, the eNB can configure the UE with an ED threshold as low as -85dBm. … Andrew Myles, Cisco

  31. RAN1/RAN4 are very defensive about the ED-only mechanism in their response to clause 1 • RAN1/RAN4 response in May 2017 (clause 1) – with commentary • Comment received by e-mail • Even though the eNB can signal the UE to use an ED threshold of -85dBm for UL transmissions, it is not likely to do so. This is made clear by the next sentence from the RAN1 LS "While RAN1 recognized the technical difficulties in operating at a very low energy threshold levels close to -85dBm by stating that “Note: Ability to signal a certain maximum energy detection threshold does not indicate feasibility of operating at that threshold value”, ". • So, instead of ending the paragraph at "as low as -85dBm" we should include the next sentence in order to make this aspect clear, that 3GPP is itself admitting that it is not likely to reduce the threshold by putting the caveats "technical difficulties in operating at a very low energy detection threshold" and "Ability to signal a certain maximum energy detection threshold does not indicate feasibility of operating at that threshold". • However, this stance can change if the RAN4 tests show very poor coexistence with ED = -72dBm. Andrew Myles, Cisco

  32. RAN1/RAN4 are very defensive about the ED-only mechanism in their response to clause 1 • RAN1/RAN4 response in May 2017 (clause 1) – with commentary • … While RAN1 recognized the technical difficulties in operating at a very low energy threshold levels close to -85dBm by stating that “Note: Ability to signal a certain maximum energy detection threshold does not indicate feasibility of operating at that threshold value”, RAN1 believes that providing this flexibility to the eNB to adapt the ED threshold to the scenario at hand is a valuable tool that can additionally enhance coexistence compared to the use of fixed thresholds. • IEEE 802 had previously noted that it is was a positive development that LAA defined a mechanism in LAA to allow a different ED threshold to be dynamically configured and that appropriate values will be studied in 3GPP RAN4 Andrew Myles, Cisco

  33. RAN1/RAN4 are very defensive about the ED-only mechanism in their response to clause 1 • RAN1/RAN4 response in May 2017 (clause 1) – with commentary • Comment received by e-mail (shared in interests of richer discussion) • There is as yet no plan in 3GPP to study appropriate ED thresholds in RAN4 • Per the RAN1 agreement, the ED threshold can be signalled from -52dBm to-85dBm in steps of 1dB • However, a UE is only required to implement an ED up to -72dBm and not below • This has been made clear by the following agreement in 3GPP, "Note: Ability to signal a certain maximum energy detection threshold does not indicate feasibility of operating at that threshold value" Andrew Myles, Cisco

  34. RAN1/RAN4 are very defensive about the ED-only mechanism in their response to clause 1 • RAN1/RAN4 response in May 2017 (clause 1) – with commentary • Next, RAN1 notes that ETSI BRAN has adopted an ED threshold of -72dBm for all systems to deployed in the 5GHz unlicensed spectrum going forward. • It is true that the current version of EN 301 893 does not allow 802.11ax to use the traditional Wi-Fi PD/ED mechanism • That is because it was not possible to specify the use of this mechanism for a standard (802.11ax) that did not exist at the time • Instead it was agreed (although the 3GPP participants are now challenging this) that the use of PD/ED by 802.11ax would be evaluated when developing the next version of EN 301 893 • IEEE 802 has now formally asked ETSI BRAN to consider allowing 802.11ax to use PD/ED when revising EN 301 803 Andrew Myles, Cisco

  35. RAN1/RAN4 are very defensive about the ED-only mechanism in their response to clause 1 • RAN1/RAN4 response in May 2017 (clause 1) – with commentary • Based on this, RAN1 previously requested that this be formally specified in the IEEE 802.11ax specification as well and expected that this could be considered as the normal deployment configuration in all regions in the world. • RAN1’s request was based on a false expectation about the next revision of EN 301 893 • However, IEEE 802 has rejected a request for harmonization of the ED threshold, and therefore RAN1 currently believes that IEEE 802 will adopt an ED threshold of -72dBm only in certain regions which adopt the EN 301 893 harmonized standard v2.1.0. • 802.11ax will have to follow the regulations in each region; if nothing changes them 802.11ax will need to adopt an ED threshold of -72dBm • However, it is hoped that EN 301 893 will be revised to allow 802.11ax (and LAA or MulteFire) to use the traditional PD/ED thresholds Andrew Myles, Cisco

  36. RAN1/RAN4 are very defensive about the ED-only mechanism in their response to clause 1 • RAN1/RAN4 response in May 2017 (clause 1) – with commentary • It has recently come to the attention of some members of RAN1 and RAN4 that some members of IEEE 802 intend to request ETSI BRAN to provide an exemption even for future 802.11 systems from -72dBm ED threshold and allow compliance with an ED threshold of -62dBm and PD of -82dBm. • It is not just some members of IEEE 802 , it is IEEE 802, as documented by the recent LS; should we formally notify RAN1 about the LS? • Some RAN1 and RAN4 members have also suggested the possibility of a new work item in ETSI BRAN. • This is true • RAN1 and RAN4 respectfully request that further discussion can take place once more concrete information is available. • Seems reasonable Andrew Myles, Cisco

  37. RAN1/RAN4 are very defensive about the ED-only mechanism in their response to clause 1 • RAN1/RAN4 response in May 2017 (clause 1) – with commentary • Note: RAN1 and RAN4 note that the term “-72dBm ED threshold” is used as a proxy for the following: -72dBm ED threshold for a 23dBm eNB transmit power and the ED threshold linearly increases up to -62dBm as the eNB transmit power reduces from 23dBm. ED threshold may also change as a function of the transmit bandwidth. • Understood and agreed • Note received by e-mail (shared in interests of richer discussion) • In the presence of Wi-Fi, LAA will only use 20MHz channels or integer multiples of it. • This restriction has been put in LAA to make it easier for Wi-Fi to detect LAA transmissions via ED. • However, if it is guaranteed that if Wi-Fi is not present in a channel, for example due to regulatory restrictions, LAA can use 10MHz channels too. • So, in the presence of Wi-Fi, LAA will only use a nominal ED of -72dBm at 23dBm transmit power and it won't change as a function of the transmit bandwidth Andrew Myles, Cisco

  38. IEEE 802’s LS noted in clause 2&3 they want to work with 3GPP, especially validating LAA using RAN4 testing • PDED ad hoc summary of next steps in March 2017 (clause 2 & 3) • In the interest of resolving these outstanding issues, IEEE 802 requests that 3GPP continue to work with IEEE 802 to gather additional evidence relating to LAA/802.11 coexistence • IEEE 802 was encouraged by 3GPP’s commitment to gather additional evidence by validating LAA/802.11 coexistence before LAA deployment using test plans developed by 3GPP RAN4 Andrew Myles, Cisco

  39. RAN1/RAN4 in their response to clause 2 & 3 did not commit to testing to validate LAA • RAN1/RAN4 response in May 2017 (clause 2 & 3) – with commentary • RAN1 and RAN4 thank IEEE 802 for its understanding and note that several stakeholders from the 802.11 community are actively participating in the discussion and specification of the LAA test plan in RAN4 and encourage other IEEE 802.11 stakeholders, whenever feasible, to directly participate in the standardization of the RAN4 test plan for LAA. RAN1 and RAN4 are always open to additionally work with IEEE 802 indirectly (via liaison statements for example) to incorporate any feedback whenever there is sufficient consensus. • The response failed to react to IEEE 802’s statement (in clause 3) that LAA devices will be required to satisfy the coexistence tests developed by 3GPP RAN4 before their deployment Andrew Myles, Cisco

  40. IEEE 802’s LS asked in clauses 4 & 5 for a commitment to use RAN4 tests to validate LAA • PDED ad hoc summary of next steps in March 2017 (clause 4 & 5) • IEEE 802 is now concerned that 3GPP may not undertake the promised LAA/802.11 coexistence tests before LAA’s deployment • IEEE 802 therefore requests that 3GPP reconfirm its previous commitment to validate LAA/ 802.11 coexistence using tests developed in 3GPP RAN4 before LAA’s deployment Andrew Myles, Cisco

  41. RAN1/RAN4 were non committal on validating LAA via RAN4 testing in its response to clauses 4 & 5 • RAN1/RAN4 response in May 2017 (clause 4 & 5) – with commentary • Per the latest time plan approved by the RAN plenary, RAN4 is expected to finalize the LAA multi-node study item by RAN4 #83 (May 2017), with approval of Technical Report TR 36.789 in RAN #76 (June 2017). • This answers IEEE 802 question about date of completion of test plan • Note by e-mail: The answer is already available from the Plenary in RP-171482 • It is out of scope of the RAN1 and RAN4 work to comment on the timeline for execution of the test plan, device certification and the expected review process. RAN plenary may provide further information to IEEE 802 regarding these aspects. • This answer fails to say how RAN1 will keep their previous commitment (in terms of process and timing) to undertake the promised LAA/802.11 coexistence tests before LAA’s deployment • If there is no agreed process or timing then it is only reasonable to assume that the commitment will not be kept Andrew Myles, Cisco

  42. RAN1/RAN4 were non committal on validating LAA via RAN4 testing in its response to clauses 4 & 5 • RAN1/RAN4 response in May 2017 (clause 4 & 5) – with commentary • If any coexistence issues have been identified, appropriate changes can be incorporated into specification by way of change requests (CRs) if they don’t impact the ASN.1 encoding (RAN2 RRC spec TS 36.331), provided there is sufficient consensus to do so. If any proposed specification changes absolutely require changes to ASN.1 encoding, then RAN plenary may discuss on the best way forward at that time based on the nature of identified issues. • This answer suggest the bar will be very high on any changes, and so we probably should not expect any as a result of the testing process • Note via e-mail (shared in interests of richer discussion) • This isn't the case. What has been stated here is the normal 3GPP procedure for changes made via CRs. • … Andrew Myles, Cisco

  43. RAN1/RAN4 were non committal on validating LAA via RAN4 testing in its response to clauses 4 & 5 • RAN1/RAN4 response in May 2017 (clause 4 & 5) – with commentary • … • If the tests show coexistence issues that can be corrected via changes in the LAA design, our expectation is that with sufficient push from the Wi-Fi organizations these will be accepted in 3GPP. • The only exception are changes that affect the signalling interface between eNB - UE or eNB - eNB i.e. the ones that are ASN.1 encoded. • Interface changes are always more difficult to adopt as issues such as backward compatibility etc have to be taken into account. • Still, the Plenary response has kept a door open for such changes by stating that "If any proposed specification changes absolutely require changes to ASN.1 encoding, then RAN plenary may discuss on the best way forward at that time based on the nature of identified issues" Andrew Myles, Cisco

  44. IEEE 802’s LS asked in clause 6 for some additional testing • PDED ad hoc summary of next steps in March 2017 (clause 6) • IEEE 802 also requests that 3GPP clarify its plans for other testing of LAA’s channel access mechanisms that may be relevant to LAA/802.11 coexistence • IEEE noted existing tests • Test of adherence to the ED threshold of -72dBm with an error tolerance of 4dB, in a single 20MHz carrier configuration only • Test of adherence to the TXOP limit of 8ms for Best Effort traffic (channel access priority class 3), in a single 20MHz carrier configuration only • IEEE 802 asked for additional tests such as • Differentiated access for different access channel priority classes via appropriate selection and adaptation of channel access parameters • Appropriate multiplexing of data of a lower access channel priority class in a COT obtained with the access parameters of a higher access channel priority class • Multicarrier channel access Andrew Myles, Cisco

  45. RAN1/RAN4 were non committal on additional RAN4 testing in its response to clause 6 • RAN1/RAN4 response in May 2017 (clause 6) – with commentary • RAN4 discussed and agreed the LBT functionalities tests as specified in TS 36.141 during Rel-13 Work Item. If there is a consensus, additional functionalities tests can be introduced in the specification by way of change requests (CRs). Current LBT functionalities tests include ED threshold test, maximum channel occupancy time and minimum idle time tests. • RAN4 told us about an additional test (min idle time), but implied there was not consensus to add more • E-mail received in response to title (shared in interests of richer discussion) • This is also not fully the case. • The way we interpret it is that the onus is on the Wi-Fi organizations to propose new tests in 3GPP which will be accepted only if there is sufficient consensus to do so. • This is normal 3GPP procedure. • … Andrew Myles, Cisco

  46. RAN1/RAN4 were non committal on additional RAN4 testing in its response to clause 6 • RAN1/RAN4 response in May 2017 (clause 6) – with commentary • … • Please note that 3GPP has now accepted mixed traffic profiles (Voice + Best Effort) for the coexistence tests. • So, the concern regarding LAA winning the channel with a higher access priority but multiplexing lower priority data will be (indirectly) assessed via the coexistence tests. • LAA has been allowed to do such multiplexing without increasing the minimum duration needed to transmit the higher priority data. • The remaining major concern is coexistence in multi-carrier environments. • It is possible to propose a new Study Item in the next 3GPP Plenary to extend the current coexistence tests to also include multi-carrier configurations. • These functionalities tests are additional tests defined for LAA, in addition to currently ongoing coexistence tests which are being developed. • This means that there are two types of tests for LAA • Functional tests for checking the ED threshold, adherence to TXOP and minimum idle time for Best Effort) • Coexistence tests to evaluate coexistence between LAA and Wi-Fi Andrew Myles, Cisco

  47. IEEE 802’s LS asked in clause 6 for RAN1/RAN4 perspective on alternative testing • PDED ad hoc summary of next steps in March 2017 (clause 7) • Alternatively, in the absence of availability of timely 3GPP RAN4 testing, IEEE 802 requests 3GPP provide its perspective on extending the Wi-Fi Alliance LTE-U tests to LAA Andrew Myles, Cisco

  48. RAN1/RAN4’s response to clause 7 indicated no interest in alternative testing • RAN1/RAN4 response in May 2017 (clause 7) – with commentary • RAN1 once again notes that LAA has been standardized with the active involvement of stakeholders of both LAA and 802.11 communities after an extensive simulation campaign. • They once again seem to be saying that IEEE 802 can’t object because some 802.11 stakeholders have been involved • Regardless, this statement has little to do with the question • RAN1’s choice of coexistence mechanism has also been adopted in ETSI BRAN harmonized standard as well. • Not quite; EN 301 893 was based on 802.11 LBT rather than LAA, although the ED threshold was agreed as a result of advocacy by 3GPP stakeholders. In addition EN 301 893 actually adopts 802.11 in its entirety • Regardless, this statement has little to do with the question Andrew Myles, Cisco

  49. RAN1/RAN4’s response to clause 7 indicated no interest in alternative testing • RAN1/RAN4 response in May 2017 (clause 7) – with commentary • RAN1 believes that the coexistence testing framework developed by RAN4 has been based on consensus (with some compromises from all the stakeholders) and it is sufficient to test the coexistence between LAA and 802.11 systems. • They are essentially saying that they are not interested in alternative approaches, but they do not address the question of timeliness • Note received by e-mail • In our opinion, the LAA - Wi-Fi coexistence tests that have been now defined in 3GPP RAN4 are a reasonably strict test of coexistence. • However, 3GPP will not commit to the critical concern of ensuring that LAA devices run and pass the test before deployment and that the results and configurations of the tests are made public. • It will instead argue that it is a standardization body and not a testing authority and that such tests have always been the purview of operators and device manufactures. • We need to counter this … Andrew Myles, Cisco

  50. How should IEEE 802 respond to the latest LS from RAN1/RAN4? • Initial comments of author (for discussion) • The LS from RAN1/RAN4 just seems to emphasise the disagreements with IEEE 802, and to indicate that RAN4 testing was unlikely to resolve the differences • There is no real commitment to validation testing (and no process or schedule) • The bar for changes as a result of testing is high • RAN1/RAN4 does not seem to want anything out of the LS exchange • There was no real action requested • What should IEEE 802 do in response? • Nothing? • Notify RAN1/RAN4 of IEEE 802’s LS to ETSI BRAN? • Ask RAN to comment on the timeline for execution of the test plan, device certification and the expected review process. • Document the lack of real cooperation (again)? Andrew Myles, Cisco

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