Review: TamoGraph Site Survey 2.0
February 14, 2011
TamoGraph Site Survey might be missing some high-end site survey features, but provides simplicity, flexibility and great reporting at a modest price.
Full Product Name, Model: TamoGraph Site Survey 2.0
Manufacturer's URL: http://www.tamos.com/
List Price: $749 (Standard) or $999 (Pro)
Pros: Easy to use, flexible and fast, rich reports, modestly-priced
Cons: No active survey, no RF planner or spectrum integration
Before WLAN deployment, two tools can be handy: a predictive planner to recommend layout and a site survey for in-situ measurements. Given 802.11n's multi-path propagation, some practitioners question whether extensive planning is worthwhile. But even for 11n, post-deployment surveys are essential to verify that installed WLANs meet and continue to satisfy each site's unique requirements.
Enterprise site survey products start around $2,000 -- in part due to features that SMBs may not need. Installers pressed for cash may want to consider TamoGraph Site Survey ($749) -- a lean-and-mean passive survey tool. No, TamoGraph won't integrate with RF planners, spectrum analyzers, or iPerf. But we found TamoGraph fast, flexible, intuitive, and easier on the wallet.
Getting started with TamoGraph
As a stand-alone product, TamoGraph requires little to get going. Just run setup on any Microsoft Windows XP, Vista, 7, Server 2003/2008 (32 or 64-bit) PC with at least 2GB of RAM and 20MB free. Size matters for on-the-go tools. But since TamoGraph doesn't run on iOS or Android, we conducted most of this review on an eeePC netbook.TamoGraph can run without live Wi-Fi -- for example, to analyze surveys on a desktop with a big monitor. But to conduct a new survey, TamoGraph needs at least one compatible 802.11a/b/g/n adapter. This supported list is solid -- especially for Windows 7 and Vista. We tested TamoGraph on XP with an AirPcap NX USB and on Windows 7 with an Atheros 9285 PCIe.
Adapter selection is crucial, because a slow/weak adapter yields too-conservative results, while a fast/sensitive adapter produces overly-optimistic surveys. Using adapter(s) representative of your own WLAN is a survey best practice. TamoGraph can use multiple adapters to scan N channels simultaneously, but those adapters must be of the same type. To survey with different adapters, walkabouts must be repeated, but TamoGraph can export and merge independently-measured results for consolidated analysis and reporting.
GPS-enabled outdoor surveys require a TamoGraph Pro license ($999) and an NMEA-compatible receiver. We paired Pro with a Holux Bluetooth GPS receiver. Like most survey tools, Pro cannot be paired with non-NMEA GPS navigators. However, we found that a Pro license is needed only to create GPS-based surveys; those results can be imported into Standard.
Creating surveys with TamoGraph
It took just fifteen minutes to install TamoGraph and complete a quick two-floor survey. We weren't tempted to consult the well-illustrated guide until we drilled into analysis. Even then, TamoGraph left little to the imagination. While not bare-bones, TamoGraph is a what-you-see-is-what-you-get tool, with few hidden knobs or nested screens, relying mostly on mouse-over detail.
TamoGraph divvies the screen into three resizable panels: scanned APs (left), site floorplan or map (center), and project parameters (right). Upon launch, clicking "New Project" runs a wizard which prompts for name/description, environment type, channel list, and map image (below). Then calibrate the floorplan or map and optionally tweak project parameters before walking the site to record passive RF measurements.
As anyone who's surveyed a site knows, the devil is in the details. Surveys are labor intensive; balky tools cause frustration and waste. To this end, TamoGraph offers a choice of three survey modes that can be used in combination to find APs heard at any site.
- Point-by-Point: With this traditional approach, the surveyor pauses at regular intervals to click on a floor plan and run a channel scan. Scanning 11 2.4 GHz channels at 250ms requires pausing just a few seconds. Increasing dwell time or scanning 5 GHz takes longer, while whittling channels or using multiple adapters can make a survey go faster. But unlike some pricier tools (e.g., AirMagnet Survey), TamoGraph cannot survey 4.9 GHz or incorporate non-Wi-Fi readings from a spectrum analyzer.
- Continuous: This mode requires less map-clicking and gathers more data, but requires the surveyor to walk at a consistent speed in straight paths, clicking only to change direction. TamoGraph distributes readings evenly between each pair of clicked points. As you might expect, we found that measurements obtained with this method were faster, but more often impacted by human error.
- GPS: This mode can fully automate outdoor surveys, which can be a huge time-saver. Following map calibration, the surveyor clicks on just one point, closes the laptop lid, and then walks or drives throughout the area. So long as the GPS continues to get a satellite fix, TamoGraph repeatedly scans the channel list until the stop button is pushed.
Each method has its strengths; fortunately, you don't have to choose just one. We used continuous mode for larger indoor areas, point-by-point in tighter and more populous spaces, and GPS for exterior perimeter surveys and neighborhood "war drives."
However, all three methods passively gather only layer two measurements. TamoGraph cannot actively associate to any AP to measure throughput or latency. If you need layer three data, either step up to an enterprise-class survey tool or take another walkabout with iPerf or WaveDeploy.