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Introduction to VHT Usage Models. Authors:. Date: 2008-11-10. Introduction to VHT Usage Models, 2008 Submission for the November 2008 IEEE Joint 802.11 VHT Group Meeting in Dallas, TX. Abstract. This submission provides an overview of the purpose, contents and scope of:
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Introduction to VHT Usage Models Authors: Date: 2008-11-10 Grodzinsky / De Vegt
Introduction to VHT Usage Models, 2008Submission for the November 2008 IEEE Joint 802.11 VHT Group Meeting in Dallas, TX Grodzinsky / De Vegt
Abstract This submission provides an overview of the purpose, contents and scope of: • the Usage Model Document that was developed in Taskgroup 11n • the VHT Usage Model Document submitted by the WFA Furthermore a set of open questions and proposed next steps regarding the Usage Model activities for the VHT Taskgroups are identified. Grodzinsky / De Vegt
Topics • Context and Introduction • Usage Models in 802.11n • WFA Submission on Usage Models • Open Questions • Proposed Next Steps Grodzinsky / De Vegt
Context and Introduction • The 802.11n Taskgroup invested a significant amount of time in the development of a Usage Model Document • Intent was the creation of Simulation Scenarios to compare 802.11n Proposals • The VHT Taskgroups are at a stage where they need to determine their plans regarding the documentation and use of Usage Models • Purpose of this document is: • Describe the contents of the 802.11n Usage Model Deliverable • Describe the contents of the WFA Deliverable on Usage Models • Describe the relationship between the Role of the Usage Models and the Nature of the Selection Procedure • Identify questions to be addressed • Propose a set of next steps Grodzinsky / De Vegt
Topics • Context and Introduction • Usage Models in 802.11n • WFA Submission on Usage Models • Open Questions • Proposed Next Steps Grodzinsky / De Vegt
Usage Models in 802.11n • 11n Usage Models documented in: IEEE802.11-03/0802r19 • Intent of Usage Model document: “This document defines usage models for 802.11 TGn, intended to be used as part of the selection process to generate simulation results for specified well-defined simulation scenarios” Grodzinsky / De Vegt
Definitions in the 802.11n Usage Model Document Application – a source or sink of wireless data that relates to a particular type of user activity. Examples: Streaming video. VOIP. Environment – The type of place a WLAN system is deployed in. Initial examples: home, large office. Use case – A use case is a description of how an end user uses a system that exercises that system’s deployment of WLAN. A use case includes an application in a deployment environment with details regarding the user activity and both sides of the link. Examples: Watching television remote from the cable or set-top box within the home. Talking on the telephone remote from one’s desk at work. Usage Model – A specification of one or more applications and environments from which a simulation scenario can be created once the traffic patterns of the applications are known. Usage models are created to "cover" use cases. Simulation Scenario – A simulation scenario is a description of a usage model that supports simulation. A simulation scenario includes details needed for simulation. Types of details to be included are descriptions that link the usage model to the simulation scenario: environment linked to a channel model, position of the AP (console or ceiling mounted), position of STAs w.r.t. AP, uplink and downlink traffic (# packets, size of packets, interference (number and types of users on the same WLAN channel – adjacent cells, the same cell, number and types of users on alternate channels, BT, baby monitors, GPRS or other systems). A simulation scenario is created from a Usage Model by characterizing the traffic profile of the applications and possibly merging multiple applications together to reduce simulation time. Grodzinsky / De Vegt
Mappings between Application, Environment, Channel Model, Use case, Usage Model and Simulation Scenario • Understanding and defining the application, environment, channel model, use case, usage model and simulation scenario are all necessary to create comparative results from 802.11 TGn proposals. • Channel models have been defined in [5], with 6 channel models. Each environment will map to a pair of channel models.. • Each use case involves the use of one or more applications and is defined for one or more environments. It represents a single type of use of a system using the technology. • Each application reflects a source or sink of data. They will eventually be characterized in terms of a traffic profile that allows a simulation of the application to be created. • Each usage model contains a representative mixture of applications and channel models designed to adequately cover the important use cases. There is a many to many mapping between use cases and usage models (i.e., the same use case may contribute to multiple usage models and the same usage model may include applications from multiple use cases). • There will be a one-to-one mapping between usage models and simulation scenarios. The usage model is a marketing-oriented description of a "reasonable mixture" covering the important use cases. The simulation scenario fills in any technical details necessary to fully define the simulation inputs not present in the usage model. Grodzinsky / De Vegt
Key: = 1:1 = 1:N = N:M Scope and Primary Purpose of the 11n Usage Model Document Scope of Document Application ApplicationMix Element Primary Purpose Environment Use Case Usage Model Simulation Scenario Comparative Results ChannelModel 11n Proposal Grodzinsky / De Vegt
Example of Use Case Definitions on 802.11n Use Case Document Grodzinsky / De Vegt
Example 11n Usage Model Description- Residential Usage Model Grodzinsky / De Vegt
Topics • Context and Introduction • Usage Models in 802.11n • WFA Submission on Usage Models • Open Questions • Proposed Next Steps Grodzinsky / De Vegt
Wi-Fi Alliance Submission on VHT Usage Models • The WFA created a VHT Usage Model Document and submitted it to IEEE 802.11 (doc. 07/2988r4) • This submission embodies the results of discussions taken place in the Wi-Fi Alliance (WFA) Very High Throughput Study Group. The document contains usage model information intended to provide key input for the a PAR and 5 Criteria discussions inside the IEEE 802.11 VHT SG. • The document contains an overview of usage environments, 21 usage models across 6 categories and a prioritization framework for the usage models, based on anticipated market volume and anticipated market timing. Grodzinsky / De Vegt
Overview Of Usage Models Grodzinsky / De Vegt
Example of Prioritizing based on Market Volume and Anticipated Market Timing RelativelyHigh Market Volume Rela-tivelyLow Later Sooner Anticipated Market Timing For Mainstream Market Grodzinsky / De Vegt
Scope of the WFA VHT Usage Model Document Scope of WFAUsage Model Document Application ApplicationMix Element Environment Use Case Usage Model Simulation Scenario Comparative Results ChannelModel 11n Proposal Key: = 1:1 = 1:N = N:M Grodzinsky / De Vegt
Topics • Context and Introduction • Usage Models in 802.11n • WFA Submission on Usage Models • Open Questions • Proposed Next Steps Grodzinsky / De Vegt
Open Question Regarding Selection Procedure and Role of Usage Models and Simulation Scenarios • The original intent for the 11n Usage Model activity was the creation of simulation scenarios for the comparison of various 802.11n Proposals • Arguably, looking back, this comparison simulation activity ended up being less relevant than initially anticipated • The importance and level of detail required for the Usage Model definition will depend on the proposed role in the Selection Procedure • In case the Taskgroup decides to follow a more ‘Organic’ proposal development process (e.g. as outlined in document 08/579r1), the group may elect to reduce the time spent of the creation of Simulation Scenarios • In the case of a Rigorous Proposal Down-select Selection Procedure, more work is needed to create the actual Simulation Scenarios Grodzinsky / De Vegt
Open Questions • Are there any additional Use Cases that the Taskgroup should consider, in addition to the Cases identified by the WFA? • Should there be separate documents for 60GHz Use Cases and VHT L6 Use Cases? • Does the Taskgroup plan to conduct all activities related to ‘Simulation Scenario Development’ and actual comparison of competing proposals using Simulation Scenarios? • What Additional activities need to be conducted with regards to the Usage Models for VHT60 and VHT L6? Grodzinsky / De Vegt
Topics • Context and Introduction • Usage Models in 802.11n • WFA Submission on Usage Models • Open Questions • Proposed Next Steps Grodzinsky / De Vegt
Proposed Next Steps • Decide whether additional Use Cases need to be added • Decide whether we need to split the document into a VHT60 and a VHTL6 document • Decide on role of Usage Models in Selection Procedure • Other? Grodzinsky / De Vegt