2.3. Controlling NetworkManager

2.3. Controlling NetworkManager
	Chapter 2. Managing Network Connections with NetworkManager

Both KDE and GNOME have their own applets for NetworkManager. An appropriate applet should start automatically with the desktop environment. The applet is then shown as an icon in the system tray. Functions of both applets are similar, but their interfaces are a little different. They can also be used in other graphical environments with standard system tray support.

Using a tray applet, choose a network to use explicitly at any time. Such a choice takes precedence over automatically selected networks. The chosen network is used as long as it is available, meaning that plugging a network cable in does not switch to a wired network connection automatically.

2.3.1. The KNetworkManager Applet

KNetworkManager is a KDE applet for controlling NetworkManager. If it is not running, start it with the command knetworkmanager. When it is running, an icon indicating a current network status is shown in the system tray. Depending on the state of the network connection, the panel icon changes appearance:

: The wired connection has been established.
: Currently there is no connection to the Internet.
: The wireless connection has been established. Blue bars illustrate strength of the signal. More blue bars means better signal strength.
: The connection is being established or terminated.

Right-clicking the icon opens the KNetworkManager menu with various commands for managing network connections. See Figure 2.1, “Available Networks in the KNetworkManager Applet”. The menu contains available network connections for both wired and wireless devices. If you hold the mouse cursor over them, details about the connection are displayed. The currently used connection is checked in the menu.

Figure 2.1. Available Networks in the KNetworkManager Applet

2.3.1.1. Wireless Networks

The signal strength of wireless networks is shown in the menu. Encrypted wireless networks are marked with a blue lock icon. To connect to an encrypted network, choose it from the menu. In the dialog that opens, choose the type of Encryption the network uses and enter the appropriate Passphrase or Key.

	Hidden Networks
To connect to a network that does not broadcast its service set identifier (ESSID) and therefore cannot be detected automatically, choose Connect to Other Wireless Network. In the dialog that opens, enter the ESSID and set encryption parameters if necessary.

To see all trusted and untrusted networks, click Options+Show Networks.

2.3.1.2. Dial-Up Connections

To access dial-up connections, choose Dial-Up Connections. When dial-up connections have already been defined, start the connection by clicking the connection to use. Configure Dial-Up Connections opens YaST where you can define a new dial-up connection.

2.3.2. The GNOME NetworkManager Applet

GNOME also has its own applet for NetworkManager. If it is not running, start it with the command nm-applet. When it is running, an icon is shown in the system tray. The appearance of the icon depends on the state of the network connection. If you are not sure what the icon means, hold the mouse cursor over it until an explanation appears.

Left-click the applet icon to show a menu with available networks, shown in Figure 2.2, “Available Networks in GNOME NetworkManager Applet”. The currently used connection is checked in the menu. To connect to a network, choose it from the list. To disable networking, right-click the applet icon and uncheck Enable Networking.

Figure 2.2. Available Networks in GNOME NetworkManager Applet

To get information about the current connection (including interface used, IP address, and hardware address), right-click the applet icon and choose Connection information from the menu. In this dialog, you can also configure your network devices. To do so, click Configure Networking. It opens YaST where you can define a new connection.

2.3.2.1. Wireless Networks

The signal strength of wireless networks is also shown in the menu. Encrypted wireless networks are marked with a shield icon. To connect to an encrypted network, choose it from the menu. In the dialog that opens, choose the type of Encryption the network uses and enter the appropriate Passphrase or Key.

	Hidden Networks
To connect to a network that does not broadcast its service set identifier (ESSID) and therefore cannot be detected automatically, left-click the icon and choose Connect to Other Wireless Network. In the dialog that opens, enter the ESSID and set encryption parameters if necessary.

If your wireless card supports access point mode, you can use NetworkManager for configuration. To configure your wireless card as an access point, click Create New Wireless Network. See Figure 2.3, “Access Point Configuration”. Add the network name and set the encryption in the Wireless Security.

Wireless Security

	Wireless Security
If you set Wireless Security to `None`, everybody can connect to your network, reuse your connectivity and intercept your network connection. To restrict access to your access point and to secure your connection, use encryption. You can choose from various WEP and WPA–based encryptions. If you are not sure which technology is best for you, read Section “Authentication” (Chapter 28, Wireless Communication, ↑Deployment Guide).

If you set Wireless Security to None, everybody can connect to your network, reuse your connectivity and intercept your network connection. To restrict access to your access point and to secure your connection, use encryption. You can choose from various WEP and WPA–based encryptions. If you are not sure which technology is best for you, read Section “Authentication” (Chapter 28, Wireless Communication, ↑Deployment Guide).

Figure 2.3. Access Point Configuration

To disable wireless networking, right-click the applet icon and uncheck Enable Wireless.