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Site Survey Tool - TamoGraph

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Introduction
Overview
System Requirements
Driver Installation
Licensing and Trial Version Limitations
Interface Overview
Access Point List
Floor Plan / Site Map
Plans and Surveys, Properties, and Options Panel
Main Menu
Performing a Site Survey
New Project Wizard
Calibration
Configuration
Data Collection
Understanding Survey Types: Passive, Active, and Predictive
Active Survey Configuration
Best Practices, Tips, and Tricks
Survey Job Splitting
Predictive Surveys
Drawing Walls and Other Obstructions
Drawing Attenuation Zones
Placing and Configuring Virtual APs
Working with Presets
Applying Visualizations
Working with Multi-floor Sites
Mixing Real and Virtual Data
Best Practices, Tips, and Tricks
Analyzing Data – Passive and Predictive Surveys
Selecting Data for Analysis
Adjusting AP Locations After Passive Surveys
Splitting an AP into Multiple Unique APs
Working with Multi-SSID APs
Visualization Types
Signal Level
Signal-to-Noise Ratio
Signal-to-Interference Ratio
AP Coverage Areas
Number of APs
Expected PHY Rate
Frame Format
Channel Bandwidth
Channel Map
Requirements
Analyzing Data – Active Surveys
Selecting Data for Analysis
Visualization Types
Actual PHY Rate
TCP Upstream and Downstream Rate
UDP Upstream and Downstream Rate
UDP Upstream and Downstream Loss
Round-trip Time
Associated AP
Requirements
Spectrum Analysis
Hardware Requirements
Spectrum Data Graphs
Performing Spectrum Analysis Surveys
Viewing Collected Spectrum Data
Exporting Spectrum Data
Reporting and Printing
Customizing Reports
Google Earth Integration
Configuring TamoGraph
Plans and Surveys
Properties
Plan / Map
Environment
Client Capabilities
Requirements
Scanner
Options
Colors and Value Ranges
AP Detection and Placement
Visualization Settings
Miscellaneous
Configuring GPS Receiver
Using GPS Configuration Dialog
Finding the GPS Receiver Port Number
Taking Photographs
Voice Control
Using TamoGraph in a Virtual Machine
Frequently Asked Questions
Sales and Support

Frame Format

This visualization shows what format of 802.11 frames (also called packets) is being used in the given WLAN area. Wi-Fi networks use three frame formats:

· Non-HT: This is a legacy frame format used by 802.11 a/b/g equipment.
· HT-mixed: This is a frame format introduced in the 802.11n standard. It uses a protection mechanism that allows 802.11n devices to coexist with legacy 802.11 a/b/g devices, including those that do not belong to your WLAN.
· HT-Greenfield: This is a frame format introduced in the 802.11n standard, too. Unlike in HT-mixed mode, devices operating in Greenfield mode assume that there are no legacy 802.11 a/b/g stations around using the same or adjacent channels. 802.11 a/b/g devices cannot communicate with Greenfield devices. Rather, their packets will collide, causing problems for both parties.
· VHT: This is the latest frame format introduced in the 802.11ac standard. This format is used in the 5 GHz band only. It uses a protection mechanism that allows 802.11ac devices to coexist with legacy 802.11a and 5 GHz 802.11n devices, including those that do not belong to your WLAN.

Frame format is shown for the AP that has the strongest signal in the given map area among the APs selected for analysis. This mimics the roaming behavior of client adapters that connected to the strongest AP. While other audible APs may use other frame formats, a typical adapter will connect to the AP with the strongest signal. You can deselect one or several of the selected APs to see frame formats for less strong APs.

Among the three pre-802.11ac frame formats, the best throughput is provided by HT-Greenfield. In HT-mixed format, protection mechanisms that ensure coexistence with legacy equipment reduce throughput. However, it should be noted that as per the 802.11n standard, support for HT-Greenfield frame format is not mandatory, and currently, few APs support it. In the realm of 802.11ac, VHT is the only available format.

Double-clicking on the Frame Format legend on the status bar allows you to configure the color scheme and change its value range.

Suggested Solutions

If you do not see the frame formats that you expect to see, the following solutions are suggested:

· Check your AP configuration. If you are using 802.11n equipment, see if Greenfield mode is available, if HT-Greenfield frame format is what you want. Note that some APs have the “802.11n only” option, but this option does not necessarily mean that HT-Greenfield frame format will be used. Rather, switching this option on may simply disable legacy data rates.
· Your AP's ability to send frames in HT-Greenfield format depends on the wireless environment. A Greenfield-enabled AP may fall back to HT-mixed format in some situations (e.g., when a non-802.11n device connects to the AP or when other non-Greenfield APs are detected nearby). Because of the changing environment, the site survey results regarding the frame format may change from time to time. Perform site surveys regularly.
· If you are using legacy 802.11 a/b/g equipment, consider upgrading to 802.11n or 802.11ac.
· Remember that VHT is not available in the 2.4 GHz band.