Q. Why is
TamoGraph much more affordable than the competing site survey
A. Surprisingly, this
non-technical question is probably the most frequently asked one.
TamoGraph is more affordable for a number of reasons. We don't
spend money on an impressive office in Silicon Valley. We don't fly
first class looking for more venture capital. We've been in the
software business for 15 years and we know how to work efficiently,
to maintain a high brain-to-fat ratio. We also believe that all
WLAN professionals should be able to afford a professional tool to
do their job.
Q. Do I need
a compatible Wi-Fi card to perform active surveys?
A. No, you can use pretty much
any modern Wi-Fi adapter. However, active surveys give you only a
small part of the WLAN picture. To get comprehensive information,
passive surveys are mandatory. A compatible adapter is required for
Q. My card
is not on your list of supported hardware. What are my
A. Our hardware compatibility
list includes only those cards that we've tested ourselves in our
test lab. There are other cards that may be compatible with
TamoGraph. The best way to find out if your card is compatible is
downloading our Adapter Test Utility and running it on your computer. If a
compatible adapter is installed, the utility will display its name.
Before running our test utility, make sure that you use the latest
driver supplied by your computer or adapter vendor. Visit their Web
site to download and install the latest driver version. This is
important, because the results of the test depend on the driver
that is used. The newer the driver, the better the chances that it
will work with TamoGraph. Finally, you may want to buy a compatible
card, as they are not terribly expensive these days. Or simply
order a boxed version from us; it comes with a compatible USB
Q. Why is
the left panel that is supposed to display the list of access
A. This might be the case for a
number of reasons:
not have a compatible adapter for passive surveys. The access point
list is populated only if you have a compatible adapter or if you
opened a project that already contains previously collected survey
not install the driver for your compatible adapter. Please refer to
for instructions. To verify that your compatible adapter is present
and functioning correctly, look at the lower left corner of the
application window. Your compatible adapter name should be
displayed there. If the adapter name is displayed, but the list is
still empty, contact our technical support.
TamoGraph support 802.11ac WLANs?
A. Yes, it does.
Q. Do I need
an 802.11ac adapter to survey 802.11ac WLANs?
A. This depends on the type of survey. For
passive surveys, a supported 802.11n adapter is sufficient, as long
as it is a dual-band adapter, i.e., if it can work in the 5 GHz
band. Such adapters can capture 802.11ac management frames, which
is needed for passive surveys. For active surveys, when your
adapter is associated to the WLAN to measure throughput and actual
PHY rate, you may want to use an 802.11ac adapter if you need to
know the WLAN metrics for 802.11ac clients. However, this is not
mandatory, because you may want to estimate throughput for 802.11n
clients, which are far more widely used than 802.11ac clients are
at the time of this writing. In this case, an 802.11n adapter for
active surveys will suffice.
Q. I have a
Wi-Spy USB spectrum analyzer. Do I still need a separate Wi-Fi
adapter for passive or active surveys?
A. Yes, you do. Wi-Spy can be
used for spectrum analysis only. It cannot replace a Wi-Fi adapter
because it cannot capture packets or connect to networks.
Q. If I
select a small Guess Range, then the predicted coverage at the end
of the survey does not cover the whole office area that I am
testing. Yet, if I increase the Guess Range, the coverage shadows
seem to be bigger and cover the whole office. So I am confused how
the results can have any accuracy when the Guess range can easily
be manipulated to change the outcome of the coverage
A. Survey results may have an
accuracy close to 100% only if you survey every square centimeter
of the floor plan. Of course, this is impossible in practice (and
not necessary), so the application has to do some extrapolation
work to calculate the results for areas that have not been surveyed
but that are near the walkabout path. There is a dependency between
the guess range and the environment. If you are in the middle of a
stadium field with no obstacles, Wi-Fi signal propagates freely and
can be easily predicted dozens of meters around; therefore, you can
use a greater guess range. If you are in a crowded office, signal
propagation is very complex, so using the guess range that you used
on the stadium field would be wrong. TamoGraph recommends a guess
range for each environment type; this recommended value should be
taken into account when you plan your walkabout paths. For example,
if the recommended guess range is 5 meters and you survey the area
by walking parallel paths, the distance between the parallel lines
should not exceed 5 meters. To sum this up, if you conduct a
quality survey by walking the entire area and leaving no “blank
spots,” and if your walkabout paths are not far apart, then
increasing the guess range would have almost no negative effect.
That’s because, in such a scenario, you leave no room for the
Q. I noticed
that the AP icon location affects the visualizations. When I move
the icon, the visualizations change. How can I avoid that?
A. Moving the AP icon may or
may not affect visualizations; this depends on the TamoGraph
settings. A very detailed explanation of this functionality can be
found in the
Visualization Settings chapter of this help file; see the
How AP icon
locations affect signal option description.
Q. Do I need
to link the Multi-SSID APs manually to get valid results in the SIR
A. Usually, TamoGraph tries to
group multiple SSIDs together automatically during the survey.
However, depending on specific WLAN implementations, it might not
be an error-free process. If you noticed that TamoGraph had not
detected some SSID groups correctly, it is recommended that you
link the SSIDs belonging to the same physical AP manually to get
proper SIR results. It is preferable to do manual SSID linking
after the entire passive survey is completed.
TamoGraph support multi-floor projects?
A. Yes, you can create projects
with multiple floors in TamoGraph. If you are doing a predictive
survey, simply add new floors in Floor Manager, add floor plans for
each floor, define floor height and material, and then align the
Q. Do I need
to use the Floor Manager in passive surveys? Does the program take
into account the floor materials and floor order in passive
A. No. The Floor Manager should be used for
predictive surveys only. In passive surveys, the application
collects actual signal data regardless of the floors and AP
locations; in other words, it doesn’t “care” about floors, their
order or materials.
conducted a passive survey in a multi-floor building, and some of
the APs were auto-placed on adjacent floors rather than on the
floor where they are actually located. How do I correct
A. If you know the actual
locations of the APs on the their respective floors, then for each
floor: (a) manually correct the locations of the APs that are
physically located on that floor and (b) drag the icons of all APs
that belong to other floors off the floor plan. If you don’t know
the actual locations of any APs and wish to view the signal
coverage map only, then clear all AP locations; this will make the
application use only the actual data, without any
Q. I have
one physical AP that I want to move around to simulate multiple APs
before deploying my WLAN. Can TamoGraph treat this single AP as
multiple APs so that I can estimate the characteristics of the
A. Yes, this widely used method
is called “AP-on-a-stick”. TamoGraph provides the functionality
necessary to handle such scenarios. Please see
Splitting an AP into Multiple Unique APs
appears that there are very few virtual AP templates and all of
them are for generic APs. How do I create a virtual AP that
simulates a specific model by a major Wi-Fi equipment
A. Virtual APs can be
constructed like Legos. For example, if you want to simulate
a Cisco Aironet 2700
series AP, you should
begin with the Generic dual
802.11ac template. Place
the AP on the floor map, double-click on it, configure its
properties to match the properties of the physical AP you plan to
deploy (e.g., channel width or output power), and then select the
antenna type, which in your case should be Cisco Aironet 2700
series 4 dBi. Be sure to
do this for both radios of this dual-band AP. In other words, you
use Lego bricks to build a model that matches the actual AP. You
can then save this configuration as a new template and use it in
your projects. Why don’t we provide you with a ready-to-use model?
Because we cannot know how you plan to configure your
physical Cisco Aironet 2700
series APs. For example,
we cannot know whether you plan to use 20 or 40 MHz channels in
your APs. This is why you have the utmost flexibility in creating
your own template.
Q. Is there
a way to tell the software to ignore all APs except the one with
which I am are surveying? I want to collect data for our
survey AP only and generate a report for this AP only.
A. You can have visualizations
for any set of AP, even a single AP. There are two buttons on the
toolbar that switch between the “All APs” and “Selected APs” modes,
so you can press the latter and select only one AP on the left
pane. Please note that in case of the Signal-to-Interference Ratio
visualization, the signal of the selected AP is analyzed against
all APs in the projects.
Q. Can I use
multiple adapters with TamoGraph to make the scanning process
A. Yes, TamoGraph can capture
data from multiple channels simultaneously if you use multiple
compatible USB adapters. This shortens the time needed to collect
data from the channels being scanned as you move along the survey
path, and, therefore, improves the data quality. For example, with
the default 250 ms per channel interval, it takes five seconds to
sweep through 20 channels if you use only one adapter. If you use
three adapters, the same amount of data will be collected in less
than two seconds. The following 802.11n USB adapters can be used
for multi-channel capturing: D-Link DWA-160 v.A1, v.A2, v.B2, and
v.C1, Edimax EW-7733UnD, Linksys AE3000, NETGEAR WN111 v2, NETGEAR
WNDA3100 v1, Proxim ORiNOCO 8494, SMC Networks SMCWUSB-N2, Sony
UWA-BR100, TP-Link TL-WDN3200, TP-Link TL-WN721N, TP-Link TL-
WN722N, TP-Link TL-WN821N v1, v2, and v3, TP-Link TL-WN822N v1 and
v2, Ubiquiti SR71-USB, and CACE Technologies AirPcap Ex or NX. The
following 802.11ac USB adapters can be used for multi-channel
capturing: Belkin F9L1109 v1, D-Link DWA-180 rev A1, D-Link DWA-182
rev C1, Edimax EW-7822UAC, EnGenius EUB1200AC, Linksys WUSB6300,
NETGEAR A6210, Proxim ORiNOCO 9100, TP-LINK Archer T4U, TRENDnet
TEW-805UB, and ZyXEL AC240. Note that different types of adapters
cannot be mixed; all of the adapters should be of the same model.
You should also install the same driver for all of the
Q. Some of
the channels in the scanner options window are not listed. Is this
normal? What if I want to monitor these channels? Is this normal?
What if I want to monitor these channels?
A. The answer depends on the
||Atheros-based miniPCI and miniPCIe
adapters: Depending on your country, your wireless adapter may not
support all the channels shown in that window. The channels that
are available for use in a particular country differ according to
the regulations of that country. In the United States, for example,
FCC regulations only allow channels 1 to 11 to be used in the
802.11b/g/n band. The firmware of the wireless adapters being sold
in the US is typically configured to disallow channels 12 and
||Atheros-based USB adapters, Intel 7xxx and
8xxx miniPCIe adapters, and recommended Ralink-, MediaTek-, and
Realtek-based USB adapters: All channels are always available when
using them in TamoGraph.
adapters (e.g. Intel 6xxx, Dell, or Broadcom): enabling
channels 12 and 13 may be possible. Open the TamoGraph application
folder (usually C:\Program Files\TamoGraph or C:\Program Files
(x86)\TamoGraph). You will see the file named ch1213.exe there.
Double-click on that file to execute it. Restart TamoGraph and
enable channel 12 and 13 in the scanner options; these channels
will become available for selection. Note that the adapter's
ability to capture packets on channels 12 and 13 depends on the
regulatory domain set by the laptop vendor. If the vendor enabled
them in your case, there won't be a problem. However, we've heard
of many examples when laptop vendors did not enable channels 12 and
13 even in the laptops that were sold in a country where these
channels were legal.
Q. Why is
the UDP downstream throughput value always zero?
A. This is a firewall issue.
This means that the UDP data being sent from the server cannot
reach the client. When performing UDP testing, the client sends
upstream UDP traffic to the server from a random UDP port to the
server port (27100 by default.) The return downstream traffic goes
from port 27101 to the client source port. Use this information to
configure your firewall.
Q. Why do I
see very high (over 50%) UDP downstream loss?
A. This question is answered in
the UDP Upstream
and Downstream Loss chapter.