1 / 14

New Radio Measurement Actions within the 802.11h Framework

New Radio Measurement Actions within the 802.11h Framework. Daryl Kaiser (Cisco Systems) 14 January 2003. Purpose. To review the radio measurement actions proposed in 02/677r2 To show how these measurements fit the 802.11h framework

curry
Télécharger la présentation

New Radio Measurement Actions within the 802.11h Framework

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. New Radio Measurement Actions within the 802.11h Framework Daryl Kaiser (Cisco Systems) 14 January 2003 Daryl Kaiser, Cisco Systems

  2. Purpose • To review the radio measurement actions proposed in 02/677r2 • To show how these measurements fit the 802.11h framework • In particular, the measurement request/report infrastructure Daryl Kaiser, Cisco Systems

  3. Wireless network goals that require radio measurement action • Detect possible rogue APs to help the WLAN administrator plug security holes • Quantify WLAN radio topology to facilitate automatic frequency selection and AP/client power limits • Measure BSS overlap to feed BSS overlap mitigation (TGe) and to help balance coverage, capacity and QoS • Quantify each station’s local performance to assist admissions control (TGe) and to facilitate roaming and load balancing • Detect non-802.11 interference and quantify noise to facilitate radio parameter avoidance and to inform mobile clients of situation Daryl Kaiser, Cisco Systems

  4. Summary of proposed radio measurement actions (02/677r2) • Beacon report detects possible rogue APs, quantifies WLAN radio topology and measures BSS overlap • Extended CCA report quantifies each station’s current local performance in terms of CCA busy fraction and backoff experience • Non-802.11 RPI histogram report detects non-802.11 interference and quantifies noise • Frame report identifies a station’s local contending stations • Reducing to one-liners: • What do you hear (and how much of it)? Extended CCA and RPI Histogram reports • Who do you hear? Beacon and Frame reports Daryl Kaiser, Cisco Systems

  5. 802.11h defines an infrastructure for measurement requests and measurement reports • One or more Measurement Request elements per frame Measurement Request frame Measurement Report frame Element … Element Element … Element Params Params Params Params … Measurement Report frame Element … Element One or more Measurement Report elements per frame Params Params Daryl Kaiser, Cisco Systems

  6. TGk would use the same measurement request format as 802.11h Add a category…and request/report actions • Category: 0=Spectrum Mgmt(TGh), 1=QoS Mgmt(TGe), 2=DLP(TGe), 3=Radio Measurement(TGk) • Action: TGh and TGe define actions unique to their categories, TGk=Measurement Request & Report • Dialog Token indicates the unique identity of the request …All fixed fields follow existing conventions • Activation Delay indicates the number of TBTTs to skip before executing the first request element • Measurement Offset indicates the start time offset within the beacon interval • Measurement Request elements are processed sequentially and executed in series or in parallel Category Action DialogToken Activation Delay Measurement Offset One or moreMeasurement Request elements 1 1 1 1 1 variable Daryl Kaiser, Cisco Systems

  7. Why define a new Radio Measurement category? • To distinguish radar avoidance and radio measurement capability • Stations advertising Spectrum Management can avoid radars • Stations advertising Radio Measurement can measure and report • Some TGh and TGk measurements may be similar, but… • Ultimately, these are two distinct capabilities Daryl Kaiser, Cisco Systems

  8. TGk would use 802.11h Measurement Request Element ID and the same fixed field definitions • Measurement Token is unique among the elements in a measurement request frame • Measurement Request Mode indicates (1) serial vs. parallel and (2) whether the originator wants to receive measurement requests and autonomous reports from the receiving station • Measurement Type identifies type of measurement, which defines the remaining format • 802.11h defines three types: Basic, CCA, and RPI Histogram • TGk would define new types: Beacon, Extended CCA, Non-802.11 RPI Histogram, Frame • Measurement Request contains the details of the request Element ID Length Add measurement types 1 1 Measurement Token Measurement Request Mode Measurement Type Measurement Request 1 1 1 variable Daryl Kaiser, Cisco Systems

  9. TGk measurement request details would include an extra field • Channel is identical to 802.11h • Duration is identical to 802.11h • Scan Mode would choose between passive, active and beacon table retrieval for Beacon measurement only • Other TGk measurements would not require Scan mode, and could replace it with a Spare field or eliminate it altogether Channel Duration 802.11h measurement request details 1 2 Channel Scan Modeor Spare Duration TGk measurement request details 1 1 2 Daryl Kaiser, Cisco Systems

  10. TGk would use the same measurement report format as 802.11h New category report action • Category: 0=Spectrum Mgmt(TGh), 1=QoS Mgmt(TGe), 2=DLP(TGe), 3=Radio Measurement(TGk) • Action: TGh and TGe define actions unique to their categories, TGk=Measurement Request & Report • Dialog Token indicates the unique identity of the request …This field follows existing convention • Measurement Report elements contain fixed fields and measurement type-specific fields Category Action DialogToken One or moreMeasurement Report elements 1 1 1 variable Daryl Kaiser, Cisco Systems

  11. TGk would use 802.11h Measurement Report Element ID and the same fixed field definitions • Measurement Token is the unique value from the measurement request frame • Measurement Report Mode indicates (1) serial vs. parallel and (2) whether the reporting STA is incapable of performing the requested measurement or refuses to perform it • Measurement Type identifies type of measurement, which defines the remaining format • Same as in Measurement Request. Three 802.11h types plus new TGk measurement types. • Measurement Report contains the measurement results Element ID Length New measurement types 1 1 Measurement Token Measurement Report Mode Measurement Type Measurement Report 1 1 1 variable Daryl Kaiser, Cisco Systems

  12. Some TGk measurement report details would match 802.11h formats. Others would define new formats. For example, the new Beacon Report… • PHY Type indicates the physical layer type as defined by dot11PhyType • Received Signal Strength is an absolute measurement in dBm • BSSID, Beacon Interval and Capability are copied from the received beacon or probe response • Parent TSF is the lower 4 bytes of the measuring station’s TSFTIMER at time of reception • Target TSF is the Timestamp field copied from the received beacon or probe response • Received Elements include other IEs in the received beacon or probe response Channel Duration PHY Type Received Signal Strength BSSID 1 1 1 1 6 Parent TSF Target TSF Beacon Interval Capability Information Received Elements 4 8 2 2 variable Daryl Kaiser, Cisco Systems

  13. Measurement report details for proposed TGk measurements • Beacon report would define a new report detail format • Extended CCA report would include Channel Busy Fraction as in 802.11h, plus the station’s recent backoff history per QoS class • Non-802.11 RPI histogram report would use the same format as 802.11h, but reflect only non-802.11 interference and noise • Frame report would define a new report detail format Daryl Kaiser, Cisco Systems

  14. Summary of how proposed TGk measurement requests and reports fit the 802.11 framework • Use action management frames defined by TGh and TGe • Define a new action category for radio measurements • Use Measurement Request & Report Element IDs defined by TGh • Use the same definition of CCA Busy Fraction as TGh • Use the same report RPI Histogram ranges and format as TGh Daryl Kaiser, Cisco Systems

More Related