Bugzilla – Bug 141029
NetworkManager does not show correct value for signal strengh
Last modified: 2007-06-05 09:57:56 UTC
Even though iwconfig shows a positive Link Quality value, KNetworkManager displays a zero value for Signal strengh. Please see the attached screenshot.
Created attachment 61764 [details] Signal strengh is zero, even though iwconfig reports a positive a Link Quality of 40
Joao, could you please give it a try with nm-applet and report whether it shows the signal strength correctly?
Joao, can you please re-test with Beta2 (should be released by tomorrow)? It has an updated version of NetworkManager and KNetworkManager
Created attachment 65545 [details] Signal strengh and Encrypted values in KNetwork Manager are wrong
I have re-tested now with Beta2 and the problem persists. As you can see by the attached screenshot, the value of Signal strengh does not match iwconfig's Link Quality. Also it says "Encrypted: no" which is wrong (as iwconfig shows, WEP is being used).
Where does KNetworkManager get the signal strengh from? HAL?
Can you please run `nm-tool` as root? It should tell whether NM shows a signal strength for the network. (In reply to comment #6) > Where does KNetworkManager get the signal strengh from? HAL? No, NetworkManager.
Created attachment 66479 [details] nm-tool and iwconfig output As you can see by the attached screenshot (taken using Beta3), although iwconfig shows a positive value for Link Quality, nm-tool gives 0% for Strengh and 0.000 MHz for Freq. No wonder that KNetworkManager shows wrong values. So this is a NetworkManager bug. Should a new bug be opened?
Thanks for the updates, Joao. I'll investigate this. No need to open a new bug, I'll adjust the summary and will get back to you as I have news. Moving to Beta 3.
Just noticed one curious thing: even though nm-tool and KNetworkManager yellow tooltip show a zero value for signal strengh, the KNetworkManager System Tray icon (which is a tiny bar chart) reflects the real signal strengh value. Where does it get its value from?
(In reply to comment #10) > Just noticed one curious thing: even though nm-tool and KNetworkManager yellow > tooltip show a zero value for signal strengh, the KNetworkManager System Tray > icon (which is a tiny bar chart) reflects the real signal strengh value. Where > does it get its value from? This is a bug. As long as NM does not provide accurate information about the signal strength, KNM has no possibility to determine the signal strength by itself.
In Beta4, nm-tool still doesn't report the correct signal strengh. I have tested with a non-encrypted network and nm-tool always report 100% signal strengh while, at the same time, iwconfig's Link Quality varies.
(In reply to comment #11) > This is a bug. As long as NM does not provide accurate information about the > signal strength, KNM has no possibility to determine the signal strength by > itself. Actually, I found out that is not entirely true. I tried GNOME on Beta5 and the yellow tooltip displayed when the mouse pointer is over the 'nm-applet' icon shows: «Wireless network connection to 'QD-TCF' (43%)» And that percentage value, not only is correct, but also changes dinamically. This means that nm-applet gets the correct signal strengh, even though nm-tool reports a wrong value. And this happens also with KNetworkManager. The small icon on the System Tray with the little bar chart actually shows the correct value for Signal Strengh! But the rest of KNetworkManager shows a wrong value. Please see attached screenshot for details.
Created attachment 71013 [details] As you can see, the small bar chart in the System Tray area shows the correct value (same in nm-applet). But on the other 2 places where KNetworkManager shows the signal strengh, the values are wrong.
Thanks for the updates Joao. The divergence between the signal strength shown by ifup and NM is done on purpose. NM normalizes the signal strength reported by the wireless driver to a logarithmic scale. I hope Will has an idea wrt divergence between the context menu and the signal strength shown in the tray. cc'ing Will.
s/ifup/ifconfig
Timo: The divergences are because nm-tool is showing the per-network quality and the tooltip is showing the per-device strength. In other words, we have two values here. Both a device-wide and a per-network value. A few drivers are broken and do not compute the per-network value. This is what the user is seeing here. The iwconfig value is the per-device setting and his driver displays this. The nm-tool value is the per-network and his device does not. I don't think there is a bug here, actually, except that this driver needs to be fixed. All of the places that the user is seeing zero are per-network.
No, no, no, we do have a bug! And you found it -- hooray :-) Thanks, Robert. For the progress bars and tooltips we're using net->getStrength() but we're using dev->getStrength() for the tray icon. This fits to the what I'm seeing in the attachment of comment #14.
Created attachment 71142 [details] The fix: use net->getStrength() instead of dev->getStrength(), add fallback, show correct icon if signal is zero
I've commited the fix to SVN. Joao, thanks for the testing and your patience. If you're keen on using the fixed package, please let me know. Otherwise you will not have the pleassure of getting it until Beta 8 is released (two weeks from now).
Fixed, closing.