1. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 1 Smart Grid Technology Information - May 2010 Date: 2010-5-05 Abstract: Information on 802.11 technology for inclusion in the June 2010 NIST PAP#2 Report NameCompanyAddressPhoneemail Bruce KraemerMarvell5488 Marvell Lane, Santa Clara, CA, 95054 +1-321-751-3988bkraemer@marvell.com Kaberi Banerjee

2. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 2 Introduction to the NIST PAP2 Report Report Preface This guide is the output of the Priority Action Plan number 2 (PAP#2), wireless communications for the smart grid, which is part of the Smart Grid Interoperability Panel (SGIP). PAP#2’s work area investigates the strengths, weaknesses, capabilities, and constraints of existing and emerging standards- based physical media for wireless communications. The approach is to work with the appropriate standard development organizations (SDOs) to determine the characteristics of each technology for Smart Grid application areas and types. Results are used to assess the appropriateness of wireless communications technologies for meeting Smart Grid applications’ requirements. This guide contains the smart grid reference architecture, the user applications’ requirements, candidate wireless technologies and their capabilities, a methodology to assess the appropriateness of wireless communications technologies along with an example model, and some results.

3. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 3 http://collaborate.nist.gov/twiki-sggrid/pub/SmartGrid/PAP02Wireless/NIST_Priotity_Action_Plan_2_r04.pdf

4. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 4 44 Priority Action Plan for Wireless communications (PAP#2) McLean, VA May 6, 2010 NIST

5. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 5 5 Scope of PAP 2 deliverable Guidelines for the use of wireless communications in different Smart Grid domains: Identify different Smart Grid application communication requirements Describe how well wireless communication technologies can support Smart Grid applications: Describe an evaluation approach to point out performance trends and issues Intended audience: All smart grid stakeholders including utility operators, network/communication vendors, professional and technical associations, standard setting organizations, local, state and federal agencies involved in policy, rules, and funding related to Smart Grid.

6. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 6 6 Administrative logistics Ownership: SGIP – PAP 2 No document control No copyright protection Make this a NIST Internal Report in order to provide document control and copyright Review process within PAP 2/SGIP: Consensus within PAP 2 NIST Internal review process Public release and revision: 1 st draft to be completed by June 30, 2010 Subsequent revisions as necessary

7. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 7 7 Review of draft document

8. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 8 8 Section 6: Findings and results

9. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 9 9 1.Does wireless technology X meet SG-NET requirements Y? 2.How to cover smart grid devices deployed using a particular wireless technology? 3.How many devices can a wireless technology support? For a specific topology and traffic characteristics 4.How well can device mobility be supported and what is the impact on the user application performance? 5.How well can wireless interference be tolerated and what is the impact on the user application performance? Key questions to answer

10. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 10 Caveats and things to keep in mind PAP 2 is about wireless communications therefore performance evaluation is conducted at layers 1 & 2 and on a link by link basis –A link by link performance assessment is necessary but not sufficient to assess the end-to- end performance. In order to relate wireless communications to the application communication requirements, there is a need to make assumptions regarding the presence of protocol layers above layer 2 and their mutual interactions: –Include all protocol layer overhead in size of data transmitted –Derive performance bounds within stated assumptions Performance results and quantitative numbers are always related to a specific scenario including topology, traffic characteristics, and for a given technology –General performance trends emerge based on the relationship between the various performance metrics and the input parameters.

11. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 11 Performance metrics Reliability (data transfer): the probability that a data packet successfully reaches its destination Reliability (connectivity) or Outage probability: the probability that a device cannot establish a link at maximum transmit power Delay: the time elapsed for a data packet to successfully reach its destination, including the time spent in queuing, transmission, propagation, retransmission, processing. Throughput : the packet data size in bits divided by the time it takes to reach its destination

12. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 12 Input parameters Topology –Number of devices –coverage in cell radius (meters) or distance between transmitter and receiver Traffic –Offered Load (bandwidth) –Size of the data to be transmitted (bits) –Data interarrival time (seconds) Environment –Propagation Technology –Bit rate –Effective Isotropic Radiated Power (EIRP)

13. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 13 Sample output:offered load varies while the number of devices is fixed Plots show Reliability, Throughput, Delay, and queue blocking probability metrics versus the application offered load. The plots show a common breakpoint indicated by the dashed line (at about 6.5 kb/s) where all the metrics show significant performance degradation. Breakpoint location depends on network parameters (e.g. number of stations), and on the MAC layer technology.

14. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 14 Example showing effect of varying other network parameters Example plots show Reliability, Throughput, Delay, and Pr{blocking} metrics for R max = 300 m, all other parameters the same. The plot below shows the offered load breakpoint vs. R max.

15. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 15 Section 6 structure alternatives By link –Using technology x discuss performance trends and breakpoints, i.e. reliability, delay, throughput versus number of devices, coverage, environment OR By application category –Using technology x discuss performance trends and breakpoints, i.e. reliability, delay, throughput versus number of devices, coverage, environment

16. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 16 Section 6 outline 6.1 Performance metrics 6.2 Input parameters 6.3 General performance trends 6.4 By link discussion 6.4.1 Technology X 6.4.2 Technology Y OR 6.4 By application category discussion 6.4.1 Technology X 6.4.2 Technology Y

17. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 17 17 Tools & results validation

18. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 18 18 Priority Action Plan for Wireless communications (PAP#2) McLean, VA May 6, 2010 NIST

19. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 19 19 Scope of PAP 2 deliverable Guidelines for the use of wireless communications in different Smart Grid domains: Identify different Smart Grid application communication requirements Describe how well wireless communication technologies can support Smart Grid applications: Describe an evaluation approach to point out performance trends and issues Intended audience: All smart grid stakeholders including utility operators, network/communication vendors, professional and technical associations, standard setting organizations, local, state and federal agencies involved in policy, rules, and funding related to Smart Grid.

20. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 20 20 Administrative logistics Ownership: SGIP – PAP 2 No document control No copyright protection Make this a NIST Internal Report in order to provide document control and copyright Review process within PAP 2/SGIP: Consensus within PAP 2 NIST Internal review process Public release and revision: 1 st draft to be completed by June 30, 2010 Subsequent revisions as necessary

21. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 21 21 Review of draft document

22. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 22 22 Section 6: Findings and results

23. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 23 23 1.Does wireless technology X meet SG-NET requirements Y? 2.How to cover smart grid devices deployed using a particular wireless technology? 3.How many devices can a wireless technology support? For a specific topology and traffic characteristics 4.How well can device mobility be supported and what is the impact on the user application performance? 5.How well can wireless interference be tolerated and what is the impact on the user application performance? Key questions to answer

24. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 24 Caveats and things to keep in mind PAP 2 is about wireless communications therefore performance evaluation is conducted at layers 1 & 2 and on a link by link basis –A link by link performance assessment is necessary but not sufficient to assess the end-to- end performance. In order to relate wireless communications to the application communication requirements, there is a need to make assumptions regarding the presence of protocol layers above layer 2 and their mutual interactions: –Include all protocol layer overhead in size of data transmitted –Derive performance bounds within stated assumptions Performance results and quantitative numbers are always related to a specific scenario including topology, traffic characteristics, and for a given technology –General performance trends emerge based on the relationship between the various performance metrics and the input parameters.

25. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 25 Performance metrics Reliability (data transfer): the probability that a data packet successfully reaches its destination Reliability (connectivity) or Outage probability: the probability that a device cannot establish a link at maximum transmit power Delay: the time elapsed for a data packet to successfully reach its destination, including the time spent in queuing, transmission, propagation, retransmission, processing. Throughput : the packet data size in bits divided by the time it takes to reach its destination

26. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 26 Input parameters Topology –Number of devices –coverage in cell radius (meters) or distance between transmitter and receiver Traffic –Offered Load (bandwidth) –Size of the data to be transmitted (bits) –Data interarrival time (seconds) Environment –Propagation Technology –Bit rate –Effective Isotropic Radiated Power (EIRP)

27. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 27 Sample output:offered load varies while the number of devices is fixed Plots show Reliability, Throughput, Delay, and queue blocking probability metrics versus the application offered load. The plots show a common breakpoint indicated by the dashed line (at about 6.5 kb/s) where all the metrics show significant performance degradation. Breakpoint location depends on network parameters (e.g. number of stations), and on the MAC layer technology.

28. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 28 Example showing effect of varying other network parameters Example plots show Reliability, Throughput, Delay, and Pr{blocking} metrics for R max = 300 m, all other parameters the same. The plot below shows the offered load breakpoint vs. R max.

29. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 29 Section 6 structure alternatives By link –Using technology x discuss performance trends and breakpoints, i.e. reliability, delay, throughput versus number of devices, coverage, environment OR By application category –Using technology x discuss performance trends and breakpoints, i.e. reliability, delay, throughput versus number of devices, coverage, environment

30. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 30 Section 6 outline 6.1 Performance metrics 6.2 Input parameters 6.3 General performance trends 6.4 By link discussion 6.4.1 Technology X 6.4.2 Technology Y OR 6.4 By application category discussion 6.4.1 Technology X 6.4.2 Technology Y

31. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 31 31 Tools & results validation

32. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 32 Report Outline Table of Contents Revision History............................................................................................................................................. iii Preface...................................................................................................................................................... - 1 - Authors...................................................................................................................................................... - 2 - 1 Overview of the process.................................................................................................................... - 3 - 2 Acronyms and Definitions.................................................................................................................. - 4 - 2.1 Acronyms........................................................................................................................................ - 4 - 2.2 Definitions....................................................................................................................................... - 7 - 3 Smart grid....................................................................................................................................... - 11 - 3.1 Reference Architecture................................................................................................................... - 11 - 3.2 List of actors.................................................................................................................................. - 13 - 3.3 Use Cases..................................................................................................................................... - 14 - 3.4 Application requirements................................................................................................................ - 16 - 3.4.1 Smart grid user applications’ quantitative requirements......................................................... - 16 - 3.4.2 Aggregation of requirements per actor to actor...................................................................... - 16 - 4 Wireless Technology....................................................................................................................... - 20 - 5 Evaluation approach / Modeling approach...................................................................................... - 21 - 5.1 Channel Models............................................................................................................................. - 23 - 5.1.1 Indoor-indoor environments................................................................................................... - 24 - 5.1.2 Outdoor-outdoor environments.............................................................................................. - 25 - 5.1.3 Outdoor-indoor environments................................................................................................ - 25 - 5.2 Physical Layer............................................................................................................................... - 26 - 5.3 MAC sublayer................................................................................................................................ - 26 - 5.4 Example Modeling Tool.................................................................................................................. - 26 - 5.5 Other Tools................................................................................................................................... - 27 - 6 Findings / Results........................................................................................................................... - 28 - 7 Conclusions.................................................................................................................................... - 31 - 8 References..................................................................................................................................... - 32 - 9 Bibliography.................................................................................................................................... - 32 -

33. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 33 Section 4 – Wireless Technology -Contents Outline Introduction The data collection form –Group categories –Row descriptions Clarification of the row entry Technology information (Columns) –Technology names –Technology sources –Explanation of Entries & Validation source Per Technology descriptions –Completed –Under development Reference Sources

34. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 34 Wireless Characteristics 1. Link Availability 2. Data/Media Type Supported 3. Coverage Area 4. Mobility 5. Data Rates 6. RF Utilization 7. Data Frames & Packets 8. Link Quality Optimization 9. Radio Performance Measurment & Management 10. Power Management 11. Connection Topologies 12. Connection Management 13. QoS & Traffic Prioritization 14. Location Characterization 15. Security & Security Management 16. Radio Environment 17. Intra-technology Coexistence 18. Inter-technology Coexistence 19. Unique Device Identification 20. Technology Specification Source 21. Deployment Domain Characterization 22. Exclusions

35. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 35 Wireless Technologies Cdma2000 1x and cdma2000 HRPD Cdma2000 xHRDP GMR-1 3G IPOS/DVB-S2 RSM-A IEEE 802.16 e,m IEEE 802.11 IEEE 802.15 Inmarsat BGAN LTE HSPA+ UMTS EDGE

36. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 36 Technology Description and Behavior in support of Throughput calculations Range Calculations Security

37. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 37 Technology Description Clarifications

38. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 38 Group 2: Data/Media Type Supported, b: Data; 2.1 Group 2: Data/Media Type Supported, b: Data; Over the air PHY rate What is the meaning of Data? It is in measurement units of Maximum user data rate per user in Mb/s. Since 802.15.4 gives 0.25 Mb/s one might assume that it is the physical medium rate. However with that assumption, it does not apply to the value for 802.11 of 0.70 Mb/s. Therefore one must assume another meaning. For example data rate minus protocol (and/or framing) overhead results in 0.70 Mb/s (i.e., maximum user data rate (i.e., MAC Service Data Unit)), if so then the 802.15.4 value must be changed to comply with that assumption. Agreement on a consistent meaning of Data is needed. Is it the maximum user data rate seen at the interface to/from the MAC sublayer? Is it an instantaneous data rate? Since it states Maximum user data rate per user, perhaps the number of users that was assumed for the calculation needs to be stated as well, especially when the medium is shared as in 802.11 and 802.15.4.

39. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 39 2.3 Group 5: Data Rates items c and d (Peak goodput over the air UL/DL data rate) How is the goodput calculated? Is goodput strictly calculated on a single MAC sublayer frame’s payload divided by the resulting physical layer packet? Is the goodput calculated including any CSMA overhead and the entire message exchange (e.g., data frame and acknowledgement frame)? Both 802.11 and 802.15.4 can act as either peer to peer (p2p) or AP to/from STA for 802.11 or coordinator to/from device for 802.15.4. So for the peer case UL and DL would be the same. However for the non- P2P case UL and DL might be different. Both 802.11 and 802.15 use the same channel in this case, but the protocol overhead might be different (e.g., polling a PAN coordinator to retreive data vs device sending to PAN coordinator for 802.15.4). Clarification (i.e., note) on the type of mode that is being used to achieve the values for the data rates is needed.

40. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 40 2.3.2 Sample peak goodput for 802.11 baseline Was not able to obtain 0.7 Mb/s, assuming only data transmission overhead for one data frame transmission and its associated acknoledgement. What other additional overhead assumptions were assumed? Beacon transmission? RTS/CTS? Association and authentication procedures? 2.3.2.1 (A) Assuming one message exchange of one 50us DIFS + zero backoff + long preamble (144) + PLCP (48) + 28 bytes MAC overhead + 2312 bytes user data (maximum) + 10 us SIFS + ACKnowledgement packet under DCF; a peak throughput of 0.959 Mb/s. 2.3.2.2 (B) Assuming one message exchange of one 50us DIFS + 15.5 backoff slots (average first attempt successful)+ long preamble (144) + PLCP (48) + 28 bytes MAC overhead + 2312 bytes user data (maximum) + 10 us SIFS + ACKnowledgement packet under DCF and DS; a peak throughput of 0.944 Mb/s.

41. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 41 Group 7, Data frames and packets, item a frame duration and item b Maximum packet size What is meant by frame? What is meant by packet? Are they the same or different?

42. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 42 2.4 Group 7, Data frames and packets, item a frame duration and item b Maximum packet size What is meant by frame? There are three primary Frame group types identified in 802.11 Management, Control & Data. Payload data is transported inside a data frame. The Data Frame is composed of a number of sub fields: control field, duration field, address fields, sequence field, data, frame check sequence. This collection of fields is referred to as a MAC Protocol Data Unit (MPDU). The source payload data may fit into one frame or if larger than 2312 bytes requires fragmentation and transmission using multiple data frames. When the MPDU is prepared to send out over the air there are additional fields added for preamble, start of frame delimiter and header. These fields then comprise the Physical Layer Packet Data Unit (PPDU). What is meant by packet? “Packet” is a general term that refers to the combination of control, address, and data fields described above that includes the payload data of interest. Are they the same or different? When the terms Packet and Frame are used without further qualifiers they can be considered to be equivalent.

43. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 43 Technology Description Protocol Details

44. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 44 Frame Control (2 bytes) Frame Control (2 bytes) Duration /ID (2 bytes) Duration /ID (2 bytes) Address1 (6 bytes) Address1 (6 bytes) Address2 (6 bytes) Address2 (6 bytes) Address3 (6 bytes) Address3 (6 bytes) Sequence. Control (2 bytes) Sequence. Control (2 bytes) QoS Control (2 bytes) QoS Control (2 bytes) HT Control (2 bytes) HT Control (2 bytes) 802.11 MAC and Physical Layer Data Frame Encapsulation (Ref: Draft P802.11-REVmb/D3.0, March 2010) MSDU Frame CheckSum (4 bytes) MAC MSDU CCMP Header (8 bytes) MAC Header LLC MIC (8 bytes) MIC (8 bytes) PHY MPDU PHY Layer Specific PPDU ( Example : OFDM Phy, Clause 17) PLCP Header PLCP Preamble PSDU Tail Pad Bytes

45. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 45 802.11 MAC and Physical Layer Control Frame Encapsulation (Ref: Draft P802.11-REVmb/D3.0, March 2010) Frame Control (2 bytes) Frame Control (2 bytes) Duration /ID (2 bytes) Duration /ID (2 bytes) Address1 (6 bytes) Address1 (6 bytes) Optional Address2 (6 bytes) Optional Address2 (6 bytes) Frame CheckSum (4 bytes) MAC MAC Header LLC PHY MPDU PHY Layer Specific PPDU ( Example : OFDM Phy, Clause 17) PLCP Header PLCP Preamble PSDU Tail Pad Bytes Optional Control Info (BlockAck and BlockAckReq) Optional Control Info (BlockAck and BlockAckReq) Carried Frame Control HT Control Carried Frame

46. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 46 802.11 MAC and Physical Layer Management Frame Encapsulation (Ref: Draft P802.11-REVmb/D3.0, March 2010) LLC Management Frame Body Frame Control (2 bytes) Frame Control (2 bytes) Duration /ID (2 bytes) Duration /ID (2 bytes) Address1 (6 bytes) Address1 (6 bytes) Address2 (6 bytes) Address2 (6 bytes) Address3 (6 bytes) Address3 (6 bytes) Sequence. Control (2 bytes) Sequence. Control (2 bytes) HT Control (2 bytes) HT Control (2 bytes) Frame CheckSum (4 bytes) MAC Management Frame Body MAC Header LLC PHY MMPDU PHY Layer Specific PPDU ( Example : OFDM Phy, Clause 17) PLCP Header PLCP Preamble PSDU Tail Pad Bytes

47. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 47 802.11 MAC and Physical Layer Management Frame Encapsulation (Ref: Draft P802.11-REVmb/D3.0, March 2010) LLC Management Frame Body Frame Control (2 bytes) Frame Control (2 bytes) Duration /ID (2 bytes) Duration /ID (2 bytes) Address1 (6 bytes) Address1 (6 bytes) Address2 (6 bytes) Address2 (6 bytes) Address3 (6 bytes) Address3 (6 bytes) Sequence. Control (2 bytes) Sequence. Control (2 bytes) HT Control (2 bytes) HT Control (2 bytes) Frame CheckSum (4 bytes) MAC Management Frame Body MAC Header LLC PHY MMPDU PHY Layer Specific PPDU ( Example : OFDM Phy, Clause 17) PPDU

48. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 48 Framing http://forskningsnett.uninett.no/wlan/throughput.html

49. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 49 PHY Header Details The value of the TXTIME parameter returned by the PLME_TXTIME.confirm primitive shall be calculated according to Equation (19-9): TXTIME = PreambleLengthDSSS + PLCPHeaderTimeDSSS + PreambleLengthOFDM + PLCPSignalOFDM + 4 × Ceiling((PLCPServiceBits + 8 × (NumberOfOctets) + PadBits) / NDBPS) + SignalExtension(19-9) where PreambleLengthDSSS is 144 μs if the PREAMBLE_TYPE value from the TXVECTOR parameter indicates “LONGPREAMBLE,” or 72 μs if the PREAMBLE_TYPE value from the TXVECTOR parameter indicates “SHORTPREAMBLE” =144+48 or 24+8+

50. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 50 Resulting Data Message sizes (for this selection) On-demand meter read 100 bytes TLS 25 bytes TransportTCP 20 bytes IP-SEC (Tunnel mode) 80 bytes IPv6 40 bytes IEEE 802.11 CCMP 16 bytes IEEE 802.11 28 bytes DSSS 24 bytes –---------------------------------------------------------------------- TOTALS 333 bytes Similarly for Application Error on-demand meter read –TOTALS 283 bytes Similarly for Multiple interval meter read –TOTALS1833 bytes - 2833 bytes* *Exceeds MTU of 802.11 must segment into two frames http://collaborate.nist.gov/twiki-sggrid/pub/SmartGrid/PAP02Wireless/March31NISTPresentation.ppt

51. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 51 Technology Description PHY Details

52. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 52 802.11a Throughput

53. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 53 Behavior

54. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 54 Relationship between Throughput and Payload Payload Length Throughput Lower SNR High SNR Low SNR

55. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 55 Effect of payload length on throughput for various retransmission limits (6 Mbps, SNR of 2 dB) www.mat.ucsb.edu/~ggroup/choudhury_iwcmc06.pdf

56. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 56 Throughput versus payload (18 Mbps, SNR 8dB) 10.66 Mbps 59.2% www.mat.ucsb.edu/~ggroup/choudhury_iwcmc06.pdf

57. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 57 Capacity with 5 data users in the network (SNR is 8 dB, 6 Mbps) www.mat.ucsb.edu/~ggroup/choudhury_iwcmc06.pdf

58. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 58 Throughput Calculations

59. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 59 Throughput Question 2.3.2.1 (A) Assuming one message exchange of one 50us DIFS + zero backoff + long preamble (144) + PLCP (48) + 28 bytes MAC overhead + 2312 bytes user data (maximum) + 10 us SIFS + ACKnowledgement packet under DCF; a peak throughput of 0.959 Mb/s Again, how much detail to provide? What is precise enough? How to account for theory vs practice?

60. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 60 802.11 Inter-frame Spacing

61. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 61 Frame Spacing Relationships aSIFSTime and aSlotTime are fixed per PHY. aSIFSTime is: aRxRFDelay + aRxPLCPDelay + aMACProcessingDelay + aRxTxTurnaroundTime. aSlotTime is: aCCATime + aRxTxTurnaroundTime + aAirPropagationTime + aMACProcessingDelay. The PIFS and DIFS are derived by the following equations, as illustrated in Figure 9-12. PIFS = aSIFSTime + aSlotTime DIFS = aSIFSTime + 2 × aSlotTime The EIFS is derived from the SIFS and the DIFS and the length of time it takes to transmit an ACK Control frame at the lowest PHY mandatory rate by the following equation: EIFS = aSIFSTime + DIFS + ACKTxTime where ACKTxTime is the time expressed in microseconds required to transmit an ACK frame, including preamble, PLCP header and any additional PHY dependent information, at the lowest PHY mandatory rate.

62. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 62 Basic Service Protocol - Listen Before Talk DIFS (listen) 1500 Byte User DATA PPDU 1500 Byte User DATA PPDU SIFS ACK PPDU ACK PPDU 1500 Byte User DATA PPDU 1500 Byte User DATA PPDU SIFS ACK PPDU ACK PPDU DIFS (listen) 10  s 50  s 304  s 12192  s

63. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 63 Listen Before Talk Protocol DIFS (listen) DATA PPDU DATA PPDU SIFS ACK PPDU ACK PPDU DATA PPDU DATA PPDU SIFS ACK PPDU ACK PPDU DIFS (listen)

64. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 64 Example throughput calculations - #1 1Mbps PHY rate, DCF, single sender to receiver pair, no backoff

65. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 65 Example throughput calculations - #2 1Mbps PHY rate, DCF, single sender to receiver pair, minimal backoff

66. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 66 Example 1: 11b 2Mbps Measured Throughput Analyzing Wireless LAN Security Overhead Harold Lars McCarter Thesis submitted to the Faculty of the Virginia Polytechnic Institute and State University in partial fulfillment of the requirements for the degree of Master of Science in Electrical Engineering 17-Apr-06Falls Church, Virginia http://scholar.lib.vt.edu/theses/available/etd-04202006-080941/unrestricted/mccarter_thesis.pdf

67. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 67 Example 2: Various 802.11 Reported Throughputs Huawei Quidway WA1006E Wireless Access Point http://www.sersat.com/descarga/quidway_wa1006e.pdf

68. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 68 Throughput Validation

69. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 69 Long preamble Mbit/sNet Mbit/sEfficiency 10.7574.9% 21.4170.7% 5.53.3861.5% 115.3248.4% http://forskningsnett.uninett.no/wlan/throughput.html

70. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 70 Short Preamble Mbit/sNet Mbit/sEfficiency 10.7776.9% 21.4974.3% 5.53.8369.6% 116.5259.3% http://forskningsnett.uninett.no/wlan/throughput.html

71. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 71 Short list of citations on Throughput Churong Chen; Choi Look Law;, "Throughput performance analysis and experimental evaluation of IEEE 802.11b radio link," Information, Communications & Signal Processing, 2007 6th International Conference on, vol., no., pp.1-5, 10-13 Dec. 2007 doi: 10.1109/ICICS.2007.4449813 URL: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4449813&isnumber=4449533 Na, C.; Chen, J.K.; Rappaport, T.S.;, "Measured Traffic Statistics and Throughput of IEEE 802.11b Public WLAN Hotspots with Three Different Applications," Wireless Communications, IEEE Transactions on, vol.5, no.11, pp.3296-3305, November 2006 doi: 10.1109/TWC.2006.05043 URL: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4027799&isnumber=4027759 Garg, S.; Kappes, M.;, "An experimental study of throughput for UDP and VoIP traffic in IEEE 802.11b networks," Wireless Communications and Networking, 2003. WCNC 2003. 2003 IEEE, vol.3, no., pp.1748-1753 vol.3, 20-20 March 2003 doi: 10.1109/WCNC.2003.1200651 URL: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=1200651&isnumber=27030 Bruno, R.; Conti, M.; Gregori, E.;, "Throughput Analysis of UDP and TCP Flows in IEEE 802.11b WLANs: A Simple Model and Its Validation," Techniques, Methodologies and Tools for Performance Evaluation of Complex Systems, 2005. (FIRB-Perf 2005). 2005 Workshop on, vol., no., pp. 54- 63, 19-19 Sept. 2005 doi: 10.1109/FIRB-PERF.2005.20 URL: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=1587695&isnumber=33459 Mahasukhon, P.; Hempel, M.; Song Ci; Sharif, H.;, "Comparison of Throughput Performance for the IEEE 802.11a and 802.11g Networks," Advanced Information Networking and Applications, 2007. AINA '07. 21st International Conference on, vol., no., pp.792-799, 21-23 May 2007 doi: 10.1109/AINA.2007.46 URL: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4220972&isnumber=4220857 Bruno, R.; Conti, M.; Gregori, E.;, "IEEE 802.11 optimal performances: RTS/CTS mechanism vs. basic access," Personal, Indoor and Mobile Radio Communications, 2002. The 13th IEEE International Symposium on, vol.4, no., pp. 1747- 1751 vol.4, 15-18 Sept. 2002 URL: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=1045479&isnumber=22399http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4449813&isnumber=4449533http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4027799&isnumber=4027759http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=1200651&isnumber=27030http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=1587695&isnumber=33459http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4220972&isnumber=4220857http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=1045479&isnumber=22399

72. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 72 New Smart Grid Topic at ITU

73. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 73 ITU Smart Grid Initiative by ITU Press Office Wed. May 12, 2010 Geneva - Some of the world’s biggest ICT companies have tasked a new ITU group with identifying standards needs for the world’s new Smart Grid deployments, which will bring the benefits of digital technology to the existing electricity network. The Focus Group on Smart Grid will survey existing national standards initiatives to see whether these can be adopted at an international level, and will also perform a gap analysis to identify new standardization requirements that will then be taken forward by relevant ITU-T Study Groups. This exploratory phase will be relatively short before work starts on the development of the standards necessary to support the global rollout of Smart Grid technologies. http://www.itu.int/ITU-T/newslog/ITU+Introduces+Smart+Grid+Standards+Initiative.aspx

74. doc.: IEEE 802.11-10/0505r0 Submission May 2010 Bruce Kraemer, MarvellSlide 74 TSAG - Telecommunication Standardization Advisory Group The ultimate aim of the Telecommunication Standardization Advisory Group (TSAG) is to make the ITU-T the most attractive place to come to do standards work. To this end and in recognition of the increasingly dynamic environment of information and communication technologies, TSAG overhauled ITU-T working methods to streamline approval procedures for new work items and the resulting international standards. This means that on average, a standard (ITU-T Recommendation) which took as much as four years to approve 10 years ago can now be approved in about eight weeks. For Recommendations which might have policy or regulatory implications, approval takes about nine months to allow additional consultation with the world’s governments. http://www.itu.int/net/ITU-T/info/tsag.aspx