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86 CHAPTER 8 GETTING EVERYTHING UP AND RUNNING SECURE SOCKET LAYER (SSL) The transfer of confidential or financial data across the Web to and from online banking sites, for example is nearly always protected by an additional layer of secure protection called Secure Socket Layer (SSL) HTTP. You can tell if this is the case with any site because the address will begin with https://. Additionally, most browsers display a padlock symbol at the bottom of the screen. Accessing such sites should be safe, even if your wireless connection isn t protected with either WEP or WPA. Similarly, although online shopping sites don t use SSL while you re browsing, when it s time to pay, they always use SSL. This ensures your credit card details are encrypted. If the store doesn t adopt an https:// address when you click to visit the virtual checkout, you shouldn t shop there! So, there s an argument to be made that you don t really need WEP or WPA protection if you simply use your wireless connection to browse the Internet. However, some web mail services transfer your username and password in the clear, which is to say without using SSL. This means this information could be picked up by an eavesdropper. In the case of Hotmail and Yahoo Mail, you can select secure login, but it isn t activated by default. Google Mail appears to use SSL all the time for login, but after this, your e-mail messages are transmitted across the Internet in the clear and, in theory, can be eavesdropped by anyone, anywhere. Configuring WEP WEP keys come in either hexadecimal (hex) or plain text (passphrase) varieties. Hex keys look like this in their 128-bit form: CB4C4189B1861E19BC9A9BDA59. In their 64-bit form, they will be shorter and may look similar to 4D9ED51E23. A passphrase will take the form of a single short sentence. Ubuntu can work with both 64- and 128-bit keys, as well as passphrases. Follow these steps to configure WEP (these steps assume your network card has already been configured, as described above): 1. Select System . Administration . Networking to open the Network Settings dialog box. 2. Double-click the entry in the list corresponding to your wireless card. 3. In the Key Type drop-down list, select Hexadecimal, if you have a hex key, or select Plain (ASCII), if you have a passphrase. In the WEP Key box, type the key or passphrase. Then click OK. 4. In the Network Settings dialog box, click the entry in the list for your wireless card, as shown in Figure 8-4. Select Deactivate, and then click Activate. Then click OK. 5. Test your connection by attempting to browse to a web site. If you find your card doesn t seem to work after you enter new WEP settings, try rebooting. Then open the Network Settings applet and make sure your card is activated.
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CHAPTER 8 GETTING EVERYTHING UP AND RUNNING 85 If the connection doesn t use Wireless Equivalent Privacy (WEP) protection, you can leave the WEP Key field empty (it doesn t matter what the Key Type drop-down list reads). If it does use WEP protection, continue reading for instructions on how to configure it. In most instances, wireless network cards are configured with DHCP, so that they grab a network address automatically. The nature of a wireless network, where many people might join or leave the network at will, means that using static IP addresses is a bad idea. Caution When I configured a wireless card on a desktop computer, I found that I was unable to use DHCP. The card would pause for a long time without being able to find an address. The fix was to assign a static IP address to the card. I simply examined my router s settings to find the range of IP addresses that it normally assigns via DHCP and chose one to give my PC. This occasional inability to get an address by DHCP is clearly a bug that may have been fixed by the time you read this, so consider performing a system update as soon as you re online (see Chapter 9). Using WEP or WPA Encryption Some wireless networks use the WEP or Wi-Fi Protected Access (WPA) system. These systems encrypt the data being transmitted on the network so it cannot be stolen by hackers with special equipment. Also, people can t join the wireless network unless they know the encryption key, which is basically an access code. This prevents unauthorized people from accessing the network. Note At one time just a few years ago, people walking or driving past office blocks would be able to steal a business s Internet connection! This practice, known as war driving, became a hobby for some people. It s still possible today, although businesses have realized the dangers and usually protect their networks. Additionally, connecting to a wireless network connection without permission has been made illegal in some countries. The encryption key normally takes the form of a string of letters and numbers, which you should get from your system administrator. Alternatively, you administrator may give you a passphrase, which might be a sentence in English, including spaces between words. You then enter that as a kind of long password. As of this writing, WEP encryption is supported in Ubuntu, while WPA support is still in its infancy. It s possible to get WPA working with a little hard work, but it s not something for beginners. WEP is by far the easiest choice when it comes to configuration. Although WEP has been found to be relatively easy to circumvent, for most home users, it offers sufficient protection. If possible, you should reconfigure your wireless base station to use WEP rather than WPA, and configure Ubuntu accordingly. Only if you have no choice, or if you re sufficiently confident of your Linux command-line skills, should you configure WPA.
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84 CHAPTER 8 GETTING EVERYTHING UP AND RUNNING Joining a Wireless Network A wireless (also referred to as Wi-Fi) network is, as its name suggests, a network that does away with cabling and uses radio frequencies to communicate. It s more common for notebooks and handheld computers to use wireless connections, but some desktop computers also do. Notebooks and PDAs typically use built-in wireless network cards, with an antenna built in to the case. However, some notebooks might use PCMCIA cards, which will have an external square antenna, as shown in Figure 8-3. Figure 8-3. If you use a PCMCIA wireless card, it will most likely have an external antenna. Configuring a Wireless Card The process for configuring a wireless network card is quite similar to configuring a standard Ethernet card, meaning you can follow the instructions for configuring a network card in the previous section, with the following differences: The wireless card will be identified as Wireless Connection. If your computer also has a standard Ethernet adapter in addition to wireless capabilities, you ll need to make sure you select the wireless card when choosing an adapter to configure. You need to select the base station you wish to connect to in the Network Name (ESSID) drop-down list or, if your base station is configured so it doesn t broadcast its name, you should type it manually into the Network Name (ESSID) field. If you work in an office environment, you may need to speak to your network administrator to find out the base station name.
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CHAPTER 8 GETTING EVERYTHING UP AND RUNNING 83 3. In the dialog box that appears, put a check in the Enable This Connection check box. In the Configuration drop-down list, make sure Static IP Address is highlighted. In the IP Address, Subnet Mask, and Gateway Address text boxes, fill in the relevant details. Figure 8-2 shows an example of a completed Interface Properties dialog box. Click OK after filling in the information. Figure 8-2. You can configure Ubuntu to work with DHCP networks, or you can define a static IP address. 4. In the Network Settings dialog box, click the DNS tab. 5. Click the Add button, and then type the first DNS address. Click Add again, and enter the second DNS address, if you have been given one (and then enter a third if you were given one). Click OK. Tip If you re using a static IP address with a router, such as that provided by a DSL modem, the DNS address will probably be the same as the router/gateway address. 6. Click the Connections tab in the Network Settings dialog box. 7. Click the Apply button, and then click OK. Your network connection should now work. Test it by using the web browser to visit a web site. If you find it isn t working, try rebooting. However, if your system administrator mentioned that a proxy must also be configured, you ll also need to follow the instructions in the Working with a Proxy Server section later in this chapter.
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82 CHAPTER 8 GETTING EVERYTHING UP AND RUNNING Configuring a Network Card via DHCP Most computers that connect to a broadband router or an office network receive their configuration data via the Dynamic Host Control Protocol (DHCP), which is to say that your computer receives its IP, gateway, subnet mask, and DNS addresses automatically. However, you will need to configure your network card to work via DHCP. You can do this configuration with the Network Settings applet, which can be found under the System . Administration menu. Because you re going to configure hardware settings, you ll need to enter your password to proceed. Follow these steps to configure your network card: 1. Select System . Administration . Networking to open the Network Settings dialog box. 2. You should find your Ethernet card at the top of the list. It will be identified as eth, followed by a number, such as eth0or eth1. Ubuntu should indicate that the card isn t configured. Click the entry for your Ethernet card, and then click Properties. Note Listed beneath the Ethernet card will be any other networking devices you might have, such as a dial-up modem. If you don t want to use these, you can leave them unconfigured. 3. In the Properties dialog box, put a check in the Enable This Connection check box, and make sure the Configuration drop-down list reads DHCP. Then click OK. 4. In the Network Settings dialog box, click Activate. Then click OK. 5. After a few seconds, your network card should be up and running. Test it by using the web browser to visit a site. From this point on, your network card should automatically activate each time you boot, so you should not need to return to the Network Settings applet. Configuring a Static IP Address On some networks, you might have been assigned an IP address, which you must enter manually, along with a few other networking addresses. This is referred to as a static IP address. You should speak to your system administrator or technical support person to determine these settings. Ask the administrator for your IP address, DNS server addresses (there are usually two or three of these), your subnet mask, and the router address (sometimes referred to as the gateway address). The settings you will get from your system administrator will usually be in the form of a series of four numbers separated by dots, something like 192.168.0.233. Once you know your settings, proceed as follows. 1. Select System . Administration . Networking to open the Network Settings dialog box. 2. Find your network card in the list (it should be referred to as eth0), click its entry, and then click Properties.
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CHAPTER 8 GETTING EVERYTHING UP AND RUNNING 81 Note To configure most hardware devices, you ll be asked for your password, because configuring hardware requires superuser privileges. Getting Online Getting online is vital in our modern Internet age, and Ubuntu caters to all the standard ways of doing so. Linux was built from the ground up to be an online operating system and is based on Unix, which pioneered the concept of networking computers together to share data back in the 1970s. However, none of this is to say that getting online with Ubuntu is difficult! In fact, it s very easy. Regardless of whether you use a modem, standard Ethernet card, or wireless card, the same program is used to configure your network settings under Ubuntu. Support for many makes and models of equipment is built in, so in most cases, all you need to do is enter a few configuration details. Note Linux actually runs around 60% of the computers that make the Internet work! Whenever you visit a web site, there s a strong chance that it s run using Linux. As your Linux skills increase, you ll eventually get to a stage where you, too, can run your own Internet servers. It sounds difficult, but can be quite easy. Using an Ethernet Card Ethernet is one of the oldest and most established network technologies. When we talk of Ethernet, we refer to wired networks all the computers on the network are connected by cabling to a central hub or router. (The other form of networking technology, which works without wires, is covered in the next section.) You might go online via an Ethernet card in a variety of situations. If you have DSL or cable broadband service at your home or workplace, for example, you might use a DSL router. Your computer will then connect to this router via Ethernet, and all you need to worry about on your PC is getting your Ethernet card up and running. Note Using a DSL or cable modem router is the preferred way of going online via broadband. However, some people use USB-based DSL modems, which connect to and are operated by their PC. These are covered in the Using a USB-Based DSL Modem section later in this chapter. If you re running Ubuntu on a PC in an office environment, it s likely that you will connect to the local area network using an Ethernet card. This lets your computer communicate with other computers, as well as with printers. In some offices in which an Internet connection is provided, this connection will allow you to go online.
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CHAPTER 8 GETTING EVERYTHING UP AND RUNNING Figure 8-1. Ubuntu s Device Manager program can display just about everything you need to know about attached hardware. You should be aware of a few important differences between the Windows and Ubuntu versions of Device Manager. Under Ubuntu, the list is for information only. You can t tweak any settings and must instead rely on separate pieces of configuration software. On the other hand, Ubuntu s list is far more comprehensive than that in Windows. In Ubuntu, Device Manager thoroughly probes the hardware to discover its capabilities. Perhaps the biggest difference, however, is that just because a piece of hardware is listed within Ubuntu s Device Manager doesn t mean that the hardware is configured to work with Ubuntu. In fact, it doesn t even imply that the hardware will ever work under Ubuntu. Device Manager s list is simply the result of probing devices attached to the various system buses (PCI, AGP, USB, and so on) and reporting back the data. Nonetheless, Device Manager is the best starting place if you find that a certain piece of hardware isn t working. If a piece of hardware is listed, then it proves, if nothing else, that the system recognizes that the hardware is attached. That said, it s very unlikely that you ll need to use Ubuntu s Device Manager, because most hardware will work after you install Ubuntu. At the very most, all you ll need to do is configure a few settings for the hardware.
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CHAPTER 8 GETTING EVERYTHING UP AND RUNNING 79 drivers are usually tied into particular versions of Linux. Sometimes, they can be hacked to work with other versions of Linux, but this isn t something that beginners can take on themselves. Although the folks behind Ubuntu strongly support open-source software, even they realize proprietary drivers need to be used in certain situations. For example, it s impossible to use the 3D graphics elements of most modern graphics cards unless you have a proprietary driver. Because of this, it s often possible to grab proprietary drivers from the Ubuntu online software repositories. We ll look at connecting to these software repositories later in this chapter, in the Setting Up Online Software Repositories section, and you ll also learn how to download 3D graphics card drivers, in the Installing 3D Graphics Card Drivers section. Note Linux sees hardware in a technical way, rather than in the way humans do. If you attach something like a USB CD-R/RW drive, Linux will recognize the drive hardware and attempt to make it work. It won t try to find a driver for that specific make and model of CD-R/RW drive. Thus, Linux is able to work with a wide range of hardware because a lot of hardware is actually very similar on a technical level, despite the differences in case design, model names, and even prices! WHAT HARDWARE WORKS? The question of what hardware works under Ubuntu is one that s not easily answered. However, you can take a look at http://doc.gwos.org/index.php/HCL to see if your hardware is listed. This is an informal list created by the people who run Ubuntu s online forums, and it s not comprehensive (which is to say that there may be hardware that works fine that isn t mentioned). Nor is the list guaranteed to be 100% accurate. But it s certainly worth a look. You can find a Ubuntu hardware database at http://hwdb.ubuntu.com, but at the time of writing, it s fairly primitive and shows only basic details about various users systems. However, you can help the effort by submitting your own system information to the list: click Applications . System Tools . Ubuntu Device Database. This will anonymously submit a list of your computer s hardware. It s very likely that the list will be opened up to the public very soon, so you should certainly check the site if you re thinking of adding any new hardware to your system. A search engine like Google is your best friend if the two Ubuntu hardware lists don t help. Simply search for the brand and model of your hardware and add Ubuntu to the search string. This should return results, usually from the Ubuntu forums (www.ubuntuforums.org) or an individual s blog, written by those who have found a way to make that type of hardware work. Viewing Your Hardware When using Windows, you might have come across Device Manager, the handy tool that lists your PC s hardware. Ubuntu contains a similar piece of software, as shown in Figure 8-1, which you can open by selecting System . Administration . Device Manager.
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