“802.11 Radio Measurements in Support of WLAN Management” Month 2000 doc.: IEEE 802.11-00/xxx November 2001 “802.11 Radio Measurements in Support of WLAN Management” Byoung-Jo “J” Kim, Zoran Kostic, Mathew Sherman, Harry Worstell AT&T Labs - Research NJ, USA macsbug@research.att.com kostic@research.att.com mjsherman@research.att.com hworstell@research.att.com Date: Nov. 12th, 2001 Z. Kostic and ”J” Kim, AT&T Labs - Research John Doe, His Company

Motivation for Pursuing Support for Radio Measurement in 802.11 Month 2000 doc.: IEEE 802.11-00/xxx November 2001 Motivation for Pursuing Support for Radio Measurement in 802.11 Fundamental enabler for automated WLAN management Existence of unpredictable interference in unlicensed bands Required for tools for Automatic Planning, Deployment, Maintenance Simple versions are a de-facto Need for today’s products Higher density, bigger coverage WLAN deployments are coming (Hong Kong, Singapore, Europe: Potential Operators Concerned about rapid deployment, interference management of Public WLAN) Simple Proprietary solutions exist, but opening the interfaces, allowing the interoperability and third party solutions are beneficial Needed for interoperability/radio resource management with other wireless technologies -Activities by 3G vendors in support of joint management of cellular/WLAN systems Progress in TGh & TGf: A good Starting point for RRM: DFS, TPC, IAPP Z. Kostic and ”J” Kim, AT&T Labs - Research John Doe, His Company

Thoughts on the Use of Radio Measurements November 2001 Thoughts on the Use of Radio Measurements Contained within a BSS Measurement and Reporting methods between an AP & STA’s in a single BSS Suitable for small deployment, unmanaged, Multi-dwelling, etc. Coordinated between BSS Involving multiple BSS’s Communication between APs and/or external managers over wireline networks Suitable for Large deployment, Enterprise, etc. Needed for coordination with 3G services Z. Kostic and ”J” Kim, AT&T Labs - Research

Measurements Contained Within a BSS November 2001 Measurements Contained Within a BSS Extend DCS to all 802.11 Radio Interfaces Measurements at STA’s and AP What and How to measure Where to measure (PHY/MAC) How to trigger measurements How to exchange results in Support of Autonomous Radio Resource Management Load Balancing Power control Interference management Z. Kostic and ”J” Kim, AT&T Labs - Research

Sharing the Measurements, e.g., Extending the Published MIB Month 2000 doc.: IEEE 802.11-00/xxx November 2001 Sharing the Measurements, e.g., Extending the Published MIB dot11CurrentChannel, dot11EDThreshold Radio Measurement Results by STA’s and AP’ loading (number of STA’s associated, number of STA’s, frames transmit/received during last second/min, etc.) Per STA statistics seen at AP’s Beacon transmit power (extend dot11CurrentTxPowerLevel per STA & beacon, Keep a sliding window average) Extend Counter objects to include /sec or /min averages, average number of retransmissions, etc., to reduce number of polling Traps to detect changes in the network (New beacon heard, high load, new STA joined/left, etc.) Z. Kostic and ”J” Kim, AT&T Labs - Research John Doe, His Company

Communication Means for Exchanging Measurement Results November 2001 Communication Means for Exchanging Measurement Results Among AP’s Extend IAPP to support Radio Measurement Result exchange among AP’s Among AP’s or with External Entities SNMP managers accessing MIB’s at AP’s Limited Coordination among nearby WLAN’s owned by different entities: Over-the-air Wired access is not assured. Dynamic Channel Selection Z. Kostic and ”J” Kim, AT&T Labs - Research

Extending the ideas from 802.11h November 2001 Extending the ideas from 802.11h For DFS: Channel Monitoring AP Channel Measurement Requests Channel Measurement Process in STAs Measurement reports from STAs to AP MODIFICATION: Collecting inputs (via SNMP or IAPP) from other APs and/or central radio resource manager (Need standard Mapping of measurement report to IAPP, or MIB ) AP or Manager decision making AP Channel Switch Announcement The new channel switch ! Power control Mobile decides everything, but AP can still provide SNR or Signal Strength to aid mobile to make better decisions. SNR is asymmetric due to interference. Z. Kostic and ”J” Kim, AT&T Labs - Research

Benefits of Radio Measurement Support November 2001 Benefits of Radio Measurement Support Enable Advanced Deployment, Management and Expansion Tools Economic Deployment and Management of Large-scale Networks (airports, downtown, etc) Better co-existence of independent WLAN’s Enable Higher Capacity Enable Better Load balancing More Robustness to interference Z. Kostic and ”J” Kim, AT&T Labs - Research

What to do now? Start an ad-hoc group to study the issues: November 2001 What to do now? Start an ad-hoc group to study the issues: What measurements are needed to support current and future needs (such as radio resource management) What are the basic mechanisms that need to be in 802.11 standards for radio measurement - protocols, PHY, MAC changes, MIB extension What can be done within existing TG’s to accommodate radio measurement? (MIB, TGe, TGf, TGh.) Consider creating a study group and PAR for a TG if needed We invite interested people to get involved – send e-mails to macsbug@research.att.com and kostic@research.att.com Z. Kostic and ”J” Kim, AT&T Labs - Research