Translations by Koichi Akabe

\advanced{A \acronym{MAC} address is a hardware address for your computer's network card, and entering it is sometimes important when using a cable modem connection or similar. If you know the \acronym{MAC} address of you network card, this can be entered in the appropriate text field in the \button{Wired} tab of the editing window.}

A \gls{wireless connection} is when your computer is connected to the Internet via a wireless radio network, also known as Wi-Fi. Laptop computers commonly use Wi-Fi due to their portability, making it easy to access the Internet from different rooms in the house or when traveling. In order to connect to wireless connection, you must have a working wireless network. You will usually need to purchase and install a \emph{wireless router} or \emph{access point}, although some locations will already have a wireless network established.

To manually configure a wired connection, right-click on the NetworkManager icon and select \menu{Edit Connections}. Make sure you are looking at the \button{Wired} tab inside the \window{Network Connections} window that is displayed.

{\bfseries\acronym{DNS} servers} are one or more \acronym{IP} addresses of ``Domain Name System'' servers. These servers convert standard web addresses (like \url{http://www.ubuntu.com}) into \acronym{IP} addresses such as 91.189.94.156. This step allows your computer to ``find'' the correct web site when you type in the web address you wish to visit. A minimum of one \acronym{DNS} server is required, and any additional ones are used in case the first one fails.

The {\bfseries gateway} is the \acronym{IP} address at your \acronym{ISP}'s end. It helps your computer connect or ``talk'' with their network, which acts as a ``gateway'' between your computer and the Internet.

The {\bfseries network mask} tells your computer how large the network is that it belongs to. It takes the same form as an \acronym{IP} address, but is usually something like 255.255.255.0

An {\bfseries\acronym{IP} address} is a unique address used for identifying your computer on the Internet. When connecting through \acronym{DHCP} this is likely to change at times, however, if your \acronym{ISP} has provided you with a static address then it will not. An \acronym{IP} address is always given in the form of four numbers separated by decimal points, for example, 192.168.0.2.

\gltodo{``\acronym{DHCP},'' ``\acronym{ISP}''} In order to connect with a wired connection, you need to know whether your network connection supports \gls{DHCP}. This stands for ``Dynamic Host Configuration Protocol,'' and is a way for computers on your network to automatically receive configuration information from your Internet service provider (\gls{ISP}). This is usually the quickest and easiest way of establishing a connection between your computer and your \acronym{ISP} in order to access the Internet, although some \acronym{ISP}s may provide what is called a \emph{static address} instead. If you are unsure whether your \acronym{ISP} supports \acronym{DHCP}, you may wish to contact their customer service line to check. They will also be able to provide you with information on your static address if one has been allocated to you (in many cases \acronym{ISP}s only allocate static addresses to customers upon request).

If you are still not online after following these steps, you may need to try setting up your Internet configuration manually, using a static \acronym{IP} address.

You should see a window showing details about your connection. If your \acronym{IP} address is displayed as 0.0.0.0 or starts with 169.254, then your computer was not successfully provided with an address through \acronym{DHCP}. If it shows another address, it is most likely that your connection was automatically configured correctly. To test out your Internet connection, you may want to open the \application{Firefox} web browser to try loading a web page. More information on using Firefox can be found later in this chapter.

If your network supports \acronym{DHCP}, you may already be set up for online access. To check this, click on the NetworkManager icon. There should be a ``Wired Network'' heading in the menu that is displayed. If ``Auto eth$0$'' appears directly underneath, then your computer is currently connected and probably already set up correctly for \acronym{DHCP}. If ``disconnected'' appears in gray underneath the wired network section, look below to see if an option labeled ``Auto eth$0$'' appears in the list. If so, click on it to attempt to establish a wireless connection.

\gltodo{``\acronym{DHCP},'' ``\acronym{ISP}''} In order to connect with a wired connection, you need to know whether your network connection supports \gls{DHCP}. This stands for ``Dynamic Host Configuration Protocol,'' and is a way for computers on your network to automatically receive configuration information from your Internet service provider (\gls{ISP}). This is usually the quickest and easiest way of establishing a connection between your computer and your \acronym{ISP} in order to access the Internet, although some \acronym{ISP}s may provide what is called a \emph{static address} instead. If you are unsure whether your \acronym{ISP} supports \acronym{DHCP}, you may wish to contact their customer service line to check. They will also be able to provide you with information on your static address if one has been allocated to you (in many cases \acronym{ISP}s only allocate static addresses to customers upon request).

You can also right-click on the NetworkManager icon. This will open a menu allowing you to enable or disable networking, view technical details about your current connection, or edit all connection settings. In the image above, the check box next to ``Enable Networking'' is currently selected; you can deselect it to disable all network connections. This may be useful if you need to shut off all wireless communication, such as when in an airplane.

In order to connect to the Internet in Ubuntu, you need to use the \application{NetworkManager} utility. NetworkManager allows you to turn all networking on or off, and helps you manage your wired, wireless, and other connections.

A \gls{wireless connection} is when your computer is connected to the Internet via a wireless radio network, also known as Wi-Fi. Laptop computers commonly use Wi-Fi due to their portability, making it easy to access the Internet from different rooms in the house or when traveling. In order to connect to wireless connection, you must have a working wireless network. You will usually need to purchase and install a \emph{wireless router} or \emph{access point}, although some locations will already have a wireless network established.

\newglossaryentry{wired connection}{name={wired connection}, description={A wired connection is when your computer is physically connected to a \gls{router} or \gls{Ethernet port} with a cable, this is the most common connection for desktop computers.}}

If you are in a location with Internet access, you will want to make sure you are connected in order to get the most out of your Ubuntu operating system. This section of the manual will help you check your connection and configure it where necessary. Ubuntu can connect to the Internet using a wired, wireless, or dialup connection. It also supports some more advanced connection methods, which we will briefly discuss at the end of this section.

\gltodo{``wired connection,'' ``router,'' ``Ethernet port,'' ``wireless connection,'' ``dialup connection''} A \gls{wired connection} refers to when your computer is physically connected to a \gls{router} or an \gls{Ethernet port} with a cable. This is the most common connection for desktop computers.

You can access all the functions of NetworkManager using its icon in the top panel. This icon may look different depending on whether you currently have a working connection, and whether the connection is wired or wireless. If you are unsure, try hovering your mouse over the icon until a short description appears near the cursor. This will read ``Wired network connection `Auto eth$0$' active'' (for example) if you have a working wired connection, or otherwise something else related to networking or connections such as ``No connection'' or ``Networking disabled.''

Clicking this icon will bring up a list of network connections that are available to you. If you are currently connected to the Internet, the name of this connection will be highlighted in bold.

Establishing a wired connection

If you have an \emph{Ethernet} cable running from a wall socket, a router, or some other device, then you will want to set up a wired network connection in Ubuntu.

To check if you are online, right-click on the NetworkManager icon in the top panel and select the \menu{Connection Information} option.

The list may already have an entry such as ``Auto eth$0$,'' or a similar name. If a connection is listed, select it and then click the \button{Edit} button. If no connection is listed, click the \button{Add} button instead.

If you are adding a connection, you first need to provide a name for the connection so you can distinguish it from any others that are added later. In the ``Connection name'' field, choose a name such as ``Wired connection 1.''

When you have returned to the \application{Network Connections} screen, your newly-added connection should now be listed. Click \button{Close} to return to the desktop. If your connection is configured correctly, the NetworkManager icon should have changed to show an active connection. To test if your connection is properly set up, refer to the instructions above for checking a \acronym{DHCP} connection.

Wireless

If your computer is equipped with a wireless (Wi-Fi) card and you have a wireless network nearby, you should be able to set up a wireless connection in Ubuntu.

Connecting to a wireless network for the first time