The quest for easy wireless client management on Linux continues; Eric Geier takes us on a tour of three Linux network management tools for managing roaming, profiles, and encryption keys.
We went on a mission to find, experiment with, and examine Linux programs to
help manage our Wi-Fi connections. We found many different networking utilities.
Most are based around profile-based configuration, where connection details such
as encryption keys are saved for reccurring connections. Some even support per-network IP and DNS settings. This is great, for example, if your work network
requires a static IP address, while at home your router using its DHCP server;
IP address information is saved for each network's profile. In addition to a
simple signal indicator for wireless networks, some utilities offer details such
as signal and noise level graphs and the displaying of the channels used by the
On our search, here are some of the network connectivity utilities we came
across: NetworkManager, Wicd, KWiFiManger, WaveSelect, AP
Radar, NetChoose, gWireless. We're going to review Network Manager, Wicd, and KWifiManager.
The first networking utility we'll review is NetworkManager,
an interface for both wired and wireless connections, installed by default in
Ubuntu. Though NetworkManager lacks advanced functionality, such as per network
IP settings and channel info, it includes the basic features.
As Figure 1 shows, a click on the tray icon displays all the detected Wi-Fi
networks and shortcuts to perform networking tasks. When you click a wireless
network, you're prompted if a encryption key is required and then it connects. A
profile is automatically created for the network, including any encryption keys
You can click on Connect to Other Wireless Network to manually enter a
network name (SSID) and the security type, in order to connect to non-broadcast
or hidden Wi-Fi networks. Additionally, you can create your own ad-hoc or
computer-to-computer network by clicking Create New Wireless Network.
As Figure 2 shows, right-clicking the icon lets you disable/enable the wired
and wireless connectivity. Clicking Connection Information shows you the details
of the current connection, such as the data rate, IP settings, and the hardware
(or MAC) address. To view and/or change the profiles created for networks you've
connected to, you can click Edit Wireless Networks.... Shown in Figure 3, for
each profile, you can change the security/encryption settings and, for networks
with multiple access points (APs), you can add the MAC addresses of all the APs
that use the same network name (BSSID).
You'll find NetworkManager provides a simple networking experience when
working with simple networks. You may want to look elsewhere if you work on
multiple networks that each require advanced settings (such as static IP
addresses) or need a tool that provides detailed signal strength and channel
Wicd is another utility that helps
you manage connections to wired and wireless networks. It has no Gnome
dependencies (although it does require GTK) and it should work on any Linux
distribution (distro). It can be obtained from their Website or through your
distro's repository. For specific installation instructions on a variety of
distros, see their downloads
Once installed, clicking on its tray icon opens up the Wicd Manager, where
all the action happens. As Figure 4 shows, you see an entry for the wired
connection and each Wi-Fi network with its signal strength (percentage or dBm),
encryption status, and physical (MAC) address.
Clicking an entry's arrow shows the details area, as you can see for the
dlink network in Figure 4. For wireless networks you see another piece of
information, the channel, plus buttons to configure custom scripts for the
network and to set advanced settings, such as static IP and DNS addresses and
encryption keys. Figure 5 shows all these areas: the Wicd Manager with a
network's details plus the script and advanced setting windows. The settings you
input into these windows are saved, so even if you go out of the network's
range, the settings will return the next time it's detected-sort of a
disappearing profile scheme. The details area of the wired connection is
similar, however also contains a field where you can create and pick different
profiles for the wired adapter, each configurable with static IP and DNS
Now for the application's toolbar. The Network menu provides the shortcuts to
connect to hidden wireless networks and to create a ad-hoc network. Obviously,
the Disconnect button disconnects you from the network and the Refresh button
re-scans the airwaves for a updated list of Wi-Fi signals. The Preferences
button takes you to where you can change advanced settings. Besides applying
global DNS settings and switching to displaying signals in dBm, you probably can
steer clear of these settings.
Though Wicd provides advanced features, such as profile-based IP settings,
signal strength, and channel information, it lacks a simple window displaying
the common connection details, such as the IP settings and MAC addresses.
Nevertheless, you can use other methods to get the run down of connection
details, such as by running the ifconfig -a or iwconfig command.
The last networking utility we'll look at is KWiFiManager,
for managing wireless connections. We found that though it lacks support for
wired networks, it provides a few features that make it quite useful in the
wireless arena. Lets take a tour and see.
Like the other utilities, KWiFiManager places a icon in the system tray,
however this one can even show the signal strength number in addition to its set
of animated signal bars, so you'll always have a solid idea of the signal with
just a glance. Plus you on the icon. A click of the icon brings up the
As Figure 6 shows, the Scan for Networks... button brings up a list of nearby
Wi-Fi networks. You can select one, based off its network name, signal strength,
and encryption settings, and then click Switch to Network.... Then on the
window, you'll see the connection's speed (data rate), name or SSID, MAC address
of the AP, and the channel. Plus on the left you see the signal bars and number.
From the File menu, you can disable/enable the wireless radio and bring up
the Connection Statistics window. This window shows a real-time graph of the
signal and, if enabled, noise levels. This is great for checking if RF
interference is causing connectivity problems. Plus it could even serve as a
crude tool for wireless LAN surveying.
The Settings menu offers even more geeky wireless features. When Acoustic
Scanning is enabled, the program emits tones (lower tones for weak signals and
higher for better signals) to help you find a better spot for the connection or
even the AP itself. This menu is also where you can enable the noise levels to
be shown with the signal levels on the Connection Statistics window.
Additionally, here is where you can tell the program to always display the tray
icon and/or enable the signal strength number on it.
From the Settings menu, you can also launch the Configuration Editor (see
Figure 7), where you can create profiles for wireless networks. Though the
interface is a bit crude compared to those of other utilities and only WEP
encryption is supported, it does provide profile-based management. You can enter
a network's name (SSID) and WEP keys, desired speed and power management
settings for the adapter, and specify scripts to run on successfully connection.
Wrapping It Up
Now you should have a feel for what three different Linux networking
utilities offer and how to get around their interfaces. In the end, we'd like to
recommend that for Linux and wireless newbies that are using Ubuntu, you might
want to just stick with NetworkManager. However, for those that use multiple
wireless networks and desire a utility that shows a bit more Wi-Fi details, Wicd
might be the answer. Then for those that need even more advanced wireless
features, KWiFiManager could serve great along with another utility to manage
Eric Geier is an author of many
computing and networking books, including Home
Networking All-in-One Desk Reference For Dummies (Wiley 2008) and 100
Things You Need to Know about Microsoft Windows Vista (Que 2007).
This article was first published on LinuxPlanet.com.