2.2.6. Configuring a Wi-Fi Connection
This section explains how to use NetworkManager to configure a Wi-Fi (also known as wireless or 802.11a/b/g/n) connection to an Access Point.
Quickly Connecting to an Available Access Point
The easiest way to connect to an available access point is to click on the network connection icon to activate the Notification Area applet, locate the
Service Set Identifier (
SSID) of the access point in the list of
Wi-Fi networks, and click on it. A padlock symbol indicates the access point requires authentication. If the access point is secured, a dialog prompts you for an authentication key or password.
NetworkManager tries to auto-detect the type of security used by the access point. If there are multiple possibilities,
NetworkManager guesses the security type and presents it in the
Wi-Fi security drop-down menu. To see if there are multiple choices, click the
Wi-Fi security drop-down menu and select the type of security the access point is using. If you are unsure, try connecting to each type in turn. Finally, enter the key or passphrase in the
Password field. Certain password types, such as a 40-bit WEP or 128-bit WPA key, are invalid unless they are of a requisite length. The
Connect button will remain inactive until you enter a key of the length required for the selected security type. To learn more about wireless security, see
Section 2.2.10.2, “Configuring Wi-Fi Security”.
If NetworkManager connects to the access point successfully, the Notification Area applet icon will change into a graphical indicator of the wireless connection's signal strength.
Connecting to a Hidden Wi-Fi Network
All access points have a
Service Set Identifier (
SSID) to identify them. However, an access point may be configured not to broadcast its SSID, in which case it is
hidden, and will not show up in
NetworkManager's list of
Available networks. You can still connect to a wireless access point that is hiding its SSID as long as you know its SSID, authentication method, and secrets.
To connect to a hidden wireless network, press the Super key to enter the Activities Overview, type control network and then press Enter. The Network window appears. Select Wi-Fi from the menu and then select Connect to Hidden Network to cause a dialog to appear. If you have connected to the hidden network before, use the Connection dropdown to select it, and click Connect. If you have not, leave the Connection dropdown as , enter the SSID of the hidden network, select its Wi-Fi security method, enter the correct authentication secrets, and click Connect.
Editing a Connection, or Creating a Completely New One
You can edit an existing connection that you have tried or succeeded in connecting to in the past by opening the Wi-Fi page of the Network dialog and selecting the gear wheel icon to the right of the Wi-Fi connection name. If the network is not currently in range, click History to display past connections. When you click the gear wheel icon the editing connection dialog appears. The Details window shows the connection details.
To configure a new connection whose SSID is in range, first attempt to connect to it by opening the
Network window, selecting the
Wi-Fi menu entry, and clicking the connection name (by default, the same as the SSID). If the SSID is not in range, see
Section 2.2.6, “Connecting to a Hidden Wi-Fi Network”. If the SSID is in range, the procedure is as follows:
Press the Super key to enter the Activities Overview, type control network and then press Enter. The Network settings tool appears.
Select the Wi-Fi menu entry.
Click the Wi-Fi connection profile on the right-hand side menu you want to connect to. A padlock symbol indicates a key or password is required.
If requested, enter the authentication details.
Configuring the SSID, Auto-Connect Behavior, and Availability Settings
To edit a Wi-Fi connection's settings, select Wi-Fi in the Network page and then select the gear wheel icon to the right of the Wi-Fi connection name. Select Identity. The following settings are available:
- SSID
The
Service Set Identifier (
SSID) of the access point (AP).
- BSSID
The
Basic Service Set Identifier (
BSSID) is the MAC address, also known as a
hardware address, of the specific wireless access point you are connecting to when in
Infrastructure mode. This field is blank by default, and you are able to connect to a wireless access point by
SSID without having to specify its
BSSID. If the BSSID is specified, it will force the system to associate to a specific access point only.
For ad-hoc networks, the BSSID is generated randomly by the mac80211 subsystem when the ad-hoc network is created. It is not displayed by NetworkManager
- MAC address
Like an Ethernet Network Interface Card (NIC), a wireless adapter has a unique MAC address (Media Access Control; also known as a hardware address) that identifies it to the system. Running the ip addr command will show the MAC address associated with each interface. For example, in the following ip addr output, the MAC address for the wlan0 interface (which is 00:1c:bf:02:f8:70) immediately follows the link/ether keyword:
~]# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UNKNOWN qlen 1000
link/ether 52:54:00:26:9e:f1 brd ff:ff:ff:ff:ff:ff
inet 192.168.122.251/24 brd 192.168.122.255 scope global eth0
inet6 fe80::5054:ff:fe26:9ef1/64 scope link
valid_lft forever preferred_lft forever
3: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 1000
link/ether 00:1c:bf:02:f8:70 brd ff:ff:ff:ff:ff:ff
inet 10.200.130.67/24 brd 10.200.130.255 scope global wlan0
inet6 fe80::21c:bfff:fe02:f870/64 scope link
valid_lft forever preferred_lft forever
A single system could have one or more wireless network adapters connected to it. The MAC address field therefore allows you to associate a specific wireless adapter with a specific connection (or connections). As mentioned, you can determine the MAC address using the ip addr command, and then copy and paste that value into the MAC address text-entry field.
- Cloned Address
A cloned MAC address to use in place of the real hardware address.
The following settings are common to all connection profiles:
Saving Your New (or Modified) Connection and Making Further Configurations
Once you have finished editing the wireless connection, click the
Apply button to save your configuration. Given a correct configuration, you can connect to your modified connection by selecting it from the Notification Area applet. See
Section 2.2.1, “Connecting to a Network Using a GUI” for details on selecting and connecting to a network.
You can further configure an existing connection by selecting it in the Network window and clicking the gear wheel icon to reveal the connection details.
Then, to configure:
