Doc.: IEEE 802.11-10/0505r1 Submission May 2010 Bruce Kraemer, MarvellSlide 1 Smart Grid Technology...

May 2010

Bruce Kraemer, Marvell

Slide 1

doc.: IEEE 802.11-10/0505r1

Submission

Smart Grid Technology Information - May 2010

Date: 2010-5-05Abstract: Information on 802.11 technology for inclusion in the June 2010 NIST PAP#2 Report

Name Company Address Phone emailBruce Kraemer Marvell 5488 Marvell Lane,

Santa Clara, CA, 95054

+1-321-751-3988 [email protected]

Kaberi Banerjee

May 2010


Slide 2

doc.: IEEE 802.11-10/0505r1

Submission

Application Information

• Can we further clarify the Smart Grid applications?

• Huge amount of information developed by Open SG

• Example:

• http://osgug.ucaiug.org/UtiliComm/Shared%20Documents/SG-NET%20PAP%20work-in-progress/Diagrams-wip/SG-NET-diagram-r0.5e.pdf

May 2010


Slide 3

doc.: IEEE 802.11-10/0505r1

Submission

http://osgug.ucaiug.org/UtiliComm/Shared%20Documents/Interium_Release_3/Diagrams/SG-NET-diagram-r0.5e.pdf

May 2010


Slide 4

doc.: IEEE 802.11-10/0505r1

Submission

Smart Grid Use Case Requirements Derived

Requirements included in release 3.0

Meter Read Yes Yes Direct load control In progress No Service Switch Yes Yes PHEV Yes Yes System updates In progress No Distributed GEN In progress No Distributed Storage Draft No Outage Events Yes Yes Tamper Events Draft No Meter Events Draft No Demand Response Draft No Pre-Pay Metering Yes Yes Field Force tools Not started No Distribution auto support Yes Yes Transmission auto support Not started No Pricing TOU / RTP/ CPP in progress No Configuration mgmt in progress No Accounting Mgmt in progress No Performance Mgmt in progress No Security mgmt in progress No Fault mgmt in progress No Volt/VAR Management Yes Yes

Listing of pertinent use casesIn order to create a list of functional requirements for the Smart Grid, an exercise was performed to list all pertinent use cases that involve network communication. Sources for this information include the Southern California Edison Use Cases, Grid Wise Architectural Console use cases, EPRI and others. Use cases from all of these sources were selected based upon a network requirements basis. From this research the following high level use cases have been identified

http://osgug.ucaiug.org/UtiliComm/Shared%20Documents/Interium_Release_3/SG%20Network%20System%20Requirements%20Specification%20v3.doc

May 2010


Slide 5

doc.: IEEE 802.11-10/0505r1

Submission

900+ Uses cases documented

http://osgug.ucaiug.org/UtiliComm/Shared%20Documents/Interium_Release_3/SG%20Network%20System%20Requirements%20Specification%20v3.0.xls

May 2010


Slide 6

doc.: IEEE 802.11-10/0505r1

Submission

Discussion Topics from Monday May 16There are many pieces of simulation already provided and

others being constructed. Can we provide further guidance on how the data could be used to help engineer a network? Can we begin by providing guidance on how to interpret and use the model outputs e.g average and instantaneous throughput? (Dave Halasz)

• https://mentor.ieee.org/802.11/dcn/10/11-10-0614-00-0000-smartgridnistmodeloutput.ppt

May 2010


Slide 7

doc.: IEEE 802.11-10/0505r1

Submission

Discussion Topics from Monday May 16802.11 has agreed that CCMP is thebest security

machanism to use. Since it will be used in further technical descriptions and modeling we need to further characterize the security mechanism CCMP. (Dave Halasz)

https://mentor.ieee.org/802.11/dcn/10/11-10-0605-00-0000-smartgridccmpoverhead.ppt

May 2010


Slide 8

doc.: IEEE 802.11-10/0505r1

Submission

Documentation

• Comprehensive review of NIST report draft on next Smart Grid call Wed June 2.

May 2010


Slide 9

doc.: IEEE 802.11-10/0505r1

Submission

802.11 Project Plans

• What nees to be done to further enhance 802.11 technology for Smart Grid applications?

• Increase low bit rate range ; S1G re channelize, <1000 MHz– Project under way – speedy conclusion and demonstrations needed

• Complete mesh capability: Suitable features are in S, – Project 2/3 complete. Need to complete specification to build vendor and

user confidence

• Other evolutionary needs??

• Low power: need to demonstrate how to provide WLAN devices with 10 year+ battery life

May 2010


Slide 10

doc.: IEEE 802.11-10/0505r1

Submission

Technical Capabilities

• Focused discussion on how to maximize battery life with existing radio and protocol options.

• Exploration of (near term) improvements based only upon protocol extensions.

• Exploration of (longer term) improvements based upon PHY changes and protocol extensions.

May 2010


Slide 11

doc.: IEEE 802.11-10/0505r1

Submission

Following Material

Discussion Topics from Monday May 16

May 2010


Slide 12

doc.: IEEE 802.11-10/0505r1

Submission

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.

May 2010


Slide 13

doc.: IEEE 802.11-10/0505r1

Submission1313

Priority Action Plan for Wireless communications(PAP#2)

McLean, VAMay 6, 2010

NIST

http://collaborate.nist.gov/twiki-sggrid/pub/SmartGrid/PAP02Wireless/NIST_Priotity_Action_Plan_2_r04.pdf

May 2010


Slide 14

doc.: IEEE 802.11-10/0505r1

Submission14

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.

May 2010


Slide 15

doc.: IEEE 802.11-10/0505r1

Submission15

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:• 1st draft to be completed by June 30, 2010• Subsequent revisions as necessary

May 2010


Slide 16

doc.: IEEE 802.11-10/0505r1

Submission16

Review of draft document

May 2010


Slide 17

doc.: IEEE 802.11-10/0505r1

Submission17

Section 6: Findings and results

May 2010


Slide 18

doc.: IEEE 802.11-10/0505r1

Submission 18

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

May 2010


Slide 19

doc.: IEEE 802.11-10/0505r1

Submission

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.

May 2010


Slide 20

doc.: IEEE 802.11-10/0505r1

Submission

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

May 2010


Slide 21

doc.: IEEE 802.11-10/0505r1

Submission

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)

May 2010


Slide 22

doc.: IEEE 802.11-10/0505r1

Submission

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.

May 2010


Slide 23

doc.: IEEE 802.11-10/0505r1

Submission

Example showing effect of varying other network parameters

• Example plots show Reliability, Throughput, Delay, and Pr{blocking} metrics for Rmax = 300 m, all other parameters the same.

• The plot below shows the offered load breakpoint vs. Rmax.

May 2010


Slide 24

doc.: IEEE 802.11-10/0505r1

Submission

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

May 2010


Slide 25

doc.: IEEE 802.11-10/0505r1

Submission

Section 6 outline

6.1 Performance metrics6.2 Input parameters6.3 General performance trends6.4 By link discussion6.4.1 Technology X6.4.2 Technology YOR6.4 By application category discussion6.4.1 Technology X6.4.2 Technology Y

May 2010


Slide 26

doc.: IEEE 802.11-10/0505r1

Submission26

Tools & results validation

May 2010


Slide 27

doc.: IEEE 802.11-10/0505r1

Submission2727

Priority Action Plan for Wireless communications(PAP#2)

McLean, VAMay 6, 2010

NIST

May 2010


Slide 28

doc.: IEEE 802.11-10/0505r1

Submission28

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.

May 2010


Slide 29

doc.: IEEE 802.11-10/0505r1

Submission29

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:• 1st draft to be completed by June 30, 2010• Subsequent revisions as necessary

May 2010


Slide 30

doc.: IEEE 802.11-10/0505r1

Submission30

Review of draft document

May 2010


Slide 31

doc.: IEEE 802.11-10/0505r1

Submission31

Section 6: Findings and results

May 2010


Slide 32

doc.: IEEE 802.11-10/0505r1

Submission 32

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

May 2010


Slide 33

doc.: IEEE 802.11-10/0505r1

Submission

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.

May 2010


Slide 34

doc.: IEEE 802.11-10/0505r1

Submission

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

May 2010


Slide 35

doc.: IEEE 802.11-10/0505r1

Submission

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)

May 2010


Slide 36

doc.: IEEE 802.11-10/0505r1

Submission

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.

May 2010


Slide 37

doc.: IEEE 802.11-10/0505r1

Submission

Example showing effect of varying other network parameters

• Example plots show Reliability, Throughput, Delay, and Pr{blocking} metrics for Rmax = 300 m, all other parameters the same.

• The plot below shows the offered load breakpoint vs. Rmax.

May 2010


Slide 38

doc.: IEEE 802.11-10/0505r1

Submission

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

May 2010


Slide 39

doc.: IEEE 802.11-10/0505r1

Submission

Section 6 outline

6.1 Performance metrics6.2 Input parameters6.3 General performance trends6.4 By link discussion6.4.1 Technology X6.4.2 Technology YOR6.4 By application category discussion6.4.1 Technology X6.4.2 Technology Y

May 2010


Slide 40

doc.: IEEE 802.11-10/0505r1

Submission40

Tools & results validation

May 2010


Slide 41

doc.: IEEE 802.11-10/0505r1

Submission

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 -

May 2010


Slide 42

doc.: IEEE 802.11-10/0505r1

Submission

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

May 2010


Slide 43

doc.: IEEE 802.11-10/0505r1

Submission

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

May 2010


Slide 44

doc.: IEEE 802.11-10/0505r1

Submission

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

May 2010


Slide 45

doc.: IEEE 802.11-10/0505r1

Submission

Technology Description and Behavior

in support of

Throughput calculations

Range Calculations

Security

May 2010


Slide 46

doc.: IEEE 802.11-10/0505r1

Submission

Technology Description Clarifications

May 2010


Slide 47

doc.: IEEE 802.11-10/0505r1

Submission

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.

May 2010


Slide 48

doc.: IEEE 802.11-10/0505r1

Submission

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.

May 2010


Slide 49

doc.: IEEE 802.11-10/0505r1

Submission

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.

May 2010


Slide 50

doc.: IEEE 802.11-10/0505r1

Submission

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?

May 2010


Slide 51

doc.: IEEE 802.11-10/0505r1

Submission

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 802.11Management, 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.

May 2010


Slide 52

doc.: IEEE 802.11-10/0505r1

Submission

Technology Description

Protocol Details

May 2010


Slide 53

doc.: IEEE 802.11-10/0505r1

Submission

Frame Control

(2 bytes)

Frame Control

(2 bytes)

Duration /ID

(2 bytes)

Duration /ID

(2 bytes)

Address1(6 bytes)Address1(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)

MSDUMSDU

Frame CheckSum(4 bytes)


MAC

MSDUMSDUCCMP Header (8 bytes)CCMP Header (8 bytes)MAC HeaderMAC Header

LLC

MIC(8 bytes)

MIC(8 bytes)

PHY

MPDU

PHY Layer Specific PPDU ( Example : OFDM Phy , Clause 17)

PLCP HeaderPLCP HeaderPLCP PreamblePLCP Preamble PSDUPSDU TailTail Pad BytesPad Bytes

May 2010


Slide 54

doc.: IEEE 802.11-10/0505r1

Submission

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)


OptionalAddress2(6 bytes)

OptionalAddress2(6 bytes)



MAC

MAC HeaderMAC Header

LLC

PHY

MPDU



Optional Control InfoOptional Control Info

Optional Control InfoOptional Control Info

Optional Control Info(BlockAck and BlockAckReq)

Optional Control Info(BlockAck and BlockAckReq)

Carried Frame Control

Carried Frame Control

HT Control

HT Control

Carried Frame Carried Frame

May 2010


Slide 55

doc.: IEEE 802.11-10/0505r1

Submission

802.11 MAC and Physical Layer Management Frame Encapsulation(Ref: Draft P802.11-REVmb/D3.0, March 2010)

LLC LLC Management Frame Body

Management Frame Body

Frame Control

(2 bytes)

Frame Control

(2 bytes)

Duration /ID

(2 bytes)

Duration /ID

(2 bytes)




Sequence. Control

(2 bytes)

Sequence. Control

(2 bytes)

HT Control

(2 bytes)

HT Control

(2 bytes)



MAC


Management Frame BodyMAC HeaderMAC Header

LLC

PHY

MMPDU



May 2010


Slide 56

doc.: IEEE 802.11-10/0505r1

Submission

802.11 MAC and Physical Layer Management Frame Encapsulation(Ref: Draft P802.11-REVmb/D3.0, March 2010)

LLC LLC Management Frame Body


Frame Control

(2 bytes)

Frame Control

(2 bytes)

Duration /ID

(2 bytes)

Duration /ID

(2 bytes)




Sequence. Control

(2 bytes)

Sequence. Control

(2 bytes)

HT Control

(2 bytes)

HT Control

(2 bytes)



MAC


Management Frame BodyMAC HeaderMAC Header

LLC

PHY

MMPDU


PPDUPPDU

May 2010


Slide 57

doc.: IEEE 802.11-10/0505r1

Submission

Framing

http://forskningsnett.uninett.no/wlan/throughput.html

May 2010


Slide 58

doc.: IEEE 802.11-10/0505r1

Submission

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+

May 2010


Slide 59

doc.: IEEE 802.11-10/0505r1

Submission

Resulting Data Message sizes (for this selection)

• On-demand meter read 100 bytes• TLS 25 bytes• Transport TCP 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

– TOTALS 1833 bytes - 2833 bytes*• *Exceeds MTU of 802.11 must segment into two frames

http://collaborate.nist.gov/twiki-sggrid/pub/SmartGrid/PAP02Wireless/March31NISTPresentation.ppt

May 2010


Slide 60

doc.: IEEE 802.11-10/0505r1

Submission

Technology Description

PHY Details

May 2010


Slide 61

doc.: IEEE 802.11-10/0505r1

Submission

802.11a ThroughputPARAMETER

Channel BW (MHz) Modulation BPSK BPSK QPSK QPSK 16-QAM 16-QAM 64-QAM 64-QAM

Payload (PSDU/MPDU)Data Rate(Mbps) 6 9 12 18 24 36 48 54

MPDU/PSDU Length (min) (in octets) 1 1 1 1 1 1 1 1

MPDU/PSDU Length (max) (in octets) 4095 4095 4095 4095 4095 4095 4095 4095

MPDU framing basic overhead(Frame Control + 3 Address fields + DuID +Sequence Control + FCS) 28 28 28 28 28 28 28 28

MPDU framing : With CCMP overhead(+16) 44 44 44 44 44 44 44 44

MPDU framing : With CCMP and QoS overhead(+2) 46 46 46 46 46 46 46 46MSDU Length min(in octets) 1 1 1 1 1 1 1 1MSDU Length max(in octets) 2304 2304 2304 2304 2304 2304 2304 2304

MPDU Length max(in octets) 2350 2350 2350 2350 2350 2350 2350 2350

NDBPS 24 36 48 72 96 114 192 216NSYM 785 523 393 262 197 166 99 88

TSYM(us) 4 4 4 4 4 4 4 4 (Preamble+ SIGNAL) overhead(us) 20 20 20 20 20 20 20 20

PPDU Duration max(us) 3160 2112 1592 1068 808 684 416 372 Throughput(Mb/s) 5.83 8.73 11.58 17.26 22.81 26.95 44.31 49.55

Note1 :Indicates Mandatory Data Rates

Ref1 : Draft P802.11-REVmb/D3.0, March 2010, Clause 17

OFDM PHY20

May 2010


Slide 62

doc.: IEEE 802.11-10/0505r1

Submission

Behavior

May 2010


Slide 63

doc.: IEEE 802.11-10/0505r1

Submission

Relationship betweenThroughput and Payload

Payload Length

Throughput

Lower SNR

High SNR

Low SNR

May 2010


Slide 64

doc.: IEEE 802.11-10/0505r1

Submission

Effect of payload length on throughput for various retransmission limits (6 Mbps, SNR of 2 dB)

www.mat.ucsb.edu/~ggroup/choudhury_iwcmc06.pdf

May 2010


Slide 65

doc.: IEEE 802.11-10/0505r1

Submission

Throughput versus payload (18 Mbps, SNR 8dB)

10.66 Mbps59.2%


May 2010


Slide 66

doc.: IEEE 802.11-10/0505r1

Submission

Capacity with 5 data users in thenetwork (SNR is 8 dB , 6 Mbps)


May 2010


Slide 67

doc.: IEEE 802.11-10/0505r1

Submission

Throughput

Calculations

May 2010


Slide 68

doc.: IEEE 802.11-10/0505r1

Submission

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?

May 2010


Slide 69

doc.: IEEE 802.11-10/0505r1

Submission

802.11 Inter-frame Spacing

May 2010


Slide 70

doc.: IEEE 802.11-10/0505r1

Submission

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.

May 2010


Slide 71

doc.: IEEE 802.11-10/0505r1

Submission

Basic Service Protocol - Listen Before Talk

DIFS(listen)

1500 Byte User DATAPPDU


SIFS

ACKPPDUACK

PPDU



SIFS

ACKPPDUACK

PPDU

DIFS(listen)

10 s 10 s

50 s 50 s

304 s 304 s

12192 s 12192 s

May 2010


Slide 72

doc.: IEEE 802.11-10/0505r1

Submission

Listen Before Talk Protocol

DIFS(listen)

DATAPPDUDATAPPDU

SIFS

ACKPPDUACK

PPDU

DATAPPDUDATAPPDU

SIFS

ACKPPDUACK

PPDU

DIFS(listen)

May 2010


Slide 73

doc.: IEEE 802.11-10/0505r1

Submission

Example throughput calculations - #1

microsec/bit1

bitsEXAMPLE 1

difs 50 50 50 50 50 50backoff 0 0 0 0 0 0

header/adress etc transmit 192 192 192 192 192 192 192 192 192 192 192 192payload 400 400 1000 1000 1500 1500 12000 12000 15000 15000 18496 18496

sifs 10 10 10 10 10 10ack 192 192 192 192 192 192

MAC 112 112 112 112 112 112difs 50 50 50 50 50 50

backoff 0 0 0 0 0 0header/adress etc transmit 192 192 192 192 192 192 192 192 192 192 192 192

payload 400 400 1000 1000 1500 1500 12000 12000 15000 15000 18496 18496sifs 10 10 10 10 10 10

ack PHY 192 192 192 192 192 192ack MAC 112 112 112 112 112 112

microsec total 1912 3000 4000 25000 31000 37992payload bits 800 2000 3000 24000 30000 36992

payload Mbits/sec 0.418 0.667 0.750 0.960 0.9677 0.9737

1Mbps PHY rate, DCF, single sender to receiver pair, no backoff

May 2010


Slide 74

doc.: IEEE 802.11-10/0505r1

Submission

Example throughput calculations - #21Mbps PHY rate, DCF, single sender to receiver pair, minimal backoff

EXAMPLE 2difs 50 50 50 50 50 50


payload 400 400 1000 1000 1500 1500 12000 12000 15000 15000 18496 18496sifs 10 10 10 10 10 10ack 192 192 192 192 192 192

MAC 112 112 112 112 112 112difs 50 50 50 50 50 50


payload 400 400 1000 1000 1500 1500 12000 12000 15000 15000 18496 18496sifs 10 10 10 10 10 10

ack PHY 192 192 192 192 192 192ack MAC 112 112 112 112 112 112

microsec total 1943 3031 4031 25031 31031 38023payload bits 800 2000 3000 24000 30000 36992

payload Mbits/sec 0.412 0.660 0.744 0.959 0.9668 0.9729

May 2010


Slide 75

doc.: IEEE 802.11-10/0505r1

Submission

Example 1: 11b 2Mbps Measured Throughput

page 45 Open WEP 40 WEP 128 TKIP/PEAP CCMP/PEAPrates 1570.3 1559.3 1555.6 1524.2 1551.2

% 78.5% 78.0% 77.8% 76.2% 77.6%

Security Protocol

Analyzing Wireless LAN Security OverheadHarold Lars McCarterThesis submitted to the Faculty of the Virginia Polytechnic Institute and State Universityin partial fulfillment of the requirements for the degree of Master of Science in Electrical Engineering17-Apr-06Falls Church, Virginiahttp://scholar.lib.vt.edu/theses/available/etd-04202006-080941/unrestricted/mccarter_thesis.pdf

May 2010


Slide 76

doc.: IEEE 802.11-10/0505r1

Submission

Example 2: Various 802.11 Reported Throughputs

802.11g and 802.11a Modulation and Coding Options 802.11g and 802.11a Modulation and Coding Optionsover payload over payloadthe Code theair rate air

(Mbps) (Mbps) (%) (Mbps) (Mbps) (%)BPSK 1 0.81 81% BPSK 1/2 6 4.64 77%QPSK 2 1.58 79% BPSK 3/4 9 6.55 73%CCK 5.5 4.07 74% QPSK 1/2 12 8.31 69%CCK 11 7.18 65% QPSK 3/4 18 11.5 64%

16-QAM 1/2 24 14.18 59%avg 74.8% 16-QAM 3/4 36 18.31 51%

64-QAM 1/2 48 23.25 48%64-QAM 3/4 54 26.12 48%

avg 61%

Huawei Quidway WA1006E Wireless Access Point http://www.sersat.com/descarga/quidway_wa1006e.pdf

May 2010


Slide 77

doc.: IEEE 802.11-10/0505r1

Submission

Throughput

Validation

May 2010


Slide 78

doc.: IEEE 802.11-10/0505r1

Submission

Long preamble

Mbit/s Net Mbit/s Efficiency

1 0.75 74.9%

2 1.41 70.7%

5.5 3.38 61.5%

11 5.32 48.4%


May 2010


Slide 79

doc.: IEEE 802.11-10/0505r1

Submission

Short Preamble

Mbit/s Net Mbit/s Efficiency

1 0.77 76.9%

2 1.49 74.3%

5.5 3.83 69.6%

11 6.52 59.3%


May 2010


Slide 80

doc.: IEEE 802.11-10/0505r1

Submission

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. 2007doi: 10.1109/ICICS.2007.4449813URL: 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 2006doi: 10.1109/TWC.2006.05043URL: 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 2003doi: 10.1109/WCNC.2003.1200651URL: 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. 2005doi: 10.1109/FIRB-PERF.2005.20URL: 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 2007doi: 10.1109/AINA.2007.46URL: 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. 2002URL: http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=1045479&isnumber=22399

May 2010


Slide 81

doc.: IEEE 802.11-10/0505r1

Submission

New Smart Grid Topic at ITU

May 2010


Slide 82

doc.: IEEE 802.11-10/0505r1

Submission

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

May 2010


Slide 83

doc.: IEEE 802.11-10/0505r1

Submission

• 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

Doc.: IEEE 802.11-10/0505r1 Submission May 2010 Bruce Kraemer, MarvellSlide 1 Smart Grid Technology...

Documents

Transcript of Doc.: IEEE 802.11-10/0505r1 Submission May 2010 Bruce Kraemer, MarvellSlide 1 Smart Grid Technology...