IEEE%20802.11T

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IEEE 802.11T
March 2005

• Tom Alexander
• VeriWave, Inc.

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What is IEEE 802.11T?

• Task group within the IEEE 802.11 Wireless LANs
  group
• Formally created in August 2004 to recommend
  methods for testing performance of 802.11 devices
  and systems
• Goal establish a common framework, terminology
  and methodology for the 802.11 Wireless LAN
  industry

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Objectives of 802.11T

• Scope and purpose
• Official scope to provide a set of performance
  metrics, measurement methodologies, and test
  conditions to enable measuring and predicting the
  performance of 802.11 WLAN devices and networks
  at the component and application level
• Official purpose to enable testing, comparison,
  and deployment planning of 802.11 WLAN devices
  based on a common and accepted set of performance
  metrics, measurement methodologies and test
  conditions
• Output will be IEEE 802.11.2, a Recommended
  Practice
• Uses the word should

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Vital Statistics

• Officers
• Chair Charles Wright, Azimuth Systems
• Technical Editor Tom Alexander, VeriWave Inc
• Secretary none yet
• About 15 20 active members
• Sometimes up to 40 people attend
• Involvement from a broad cross-section of the
  WLAN industry
• System and chipset vendors Dell, Intel,
  Broadcom, AMD, Atheros,
• Test equipment vendors Spirent, Azimuth, Rohde
  Schwarz, VeriWave,
• Installation tools services vendors Wireless
  Valley,
• Users Microsoft, UBC, UNH-IOL,
• And some just plain interested folks
• Activity
• Meets during every 802.11 interim or Plenary for
  about 10 16 hours
• Weekly teleconferences (Thursday mornings, 9AM
  PST)
• Ad-hoc teleconferences

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Work To Date

• Scope and framework
• What kind of metrics? What sort of approach to
  measurement? What layer(s) do we include?
• Diverse group these discussions help build
  common understanding
• General consensus on some key issues
• Both open-air and conducted metrics should be
  specified
• Metrics should be somehow tied to end-user
  experience
• Etc.
• Draft structure
• Proposed templates for the overall draft and for
  individual measurement descriptions have been
  created, plus proposals for the organization of
  the standard
• Terminology
• Key discussion point in group to date (e.g.,
  What is a metric? What does controlled
  environment imply?)
• Lots of this is how we did it and this is how
  we should do it presentations
• Very useful in assessing what is possible and
  what is not
• Wireless measurement methodologies differ
  somewhat from wired

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Recent and Upcoming Work

• Convergence on some basic terminology
• Examples controlled test environment,
  conducted test, over-the-air test,
  interference, etc.
• Most of these are specific to wireless testing
  (as opposed to benchmarking in general)
• Not much disagreement (yet!) on terms such as
  latency, throughput, loss, delay, etc.
• Adoption of ground rules before voting on formal
  proposals
• Requirements for a proposal to be considered
  complete
• Format and content of formal metrics
  methodology proposals
• Timeline for first draft standard uncertain at
  the moment

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For Further Information

• The 802.11 document server
• www.802wirelessworld.com 802.11 document server
  with 802.11T contributions
• Examples of interesting contributions
• 11-04-1160-00-000t Enabling Prediction of
  Wireless Performance
• 11-04-1202-00-000t Proposed Metrics and TGT
  Call to Action
• 11-04-1222-01-000t Measurement Methodology
  Proposal Based on Approved Framework
• 11-05-1582-00-000t Environment and Metrics
  Laboratory vs. Real-world
• 11-05-0002-00-000t Proposed TGT Document
  Structure
• 11-05-0004-01-000t TGT Terminology and Concepts
• The 802.11T reflector
• March 802.11 Plenary
• March 14th to 18th, Atlanta, GA