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310 Chapter 7 Configuring Network Connectivity You can also implement a hybrid network. In this case, the WAP is typically connected to the modem as before and computers in fixed locations are connected using wired connections to Ethernet ports on the WAP. Most third-party WAPs have several Ethernet ports in addition to the wide area network (WAN) port that connects to the modem. You can wire the fixed computers directly to the WAP or you can connect them by using a switch (or a hub) and connect the switch to the WAP. Wireless-enabled devices connect directly to the WAP, and both wired and wireless devices are on the same network and obtain their IP configuration from the WAP, which provides DHCP and internal DNS services (in the case where a Wi-Fi–enabled computer provides wireless access, DHCP and DNS services are provided through ICS). The WAP forwards any datagrams that need to go to the Internet (for example, browser requests) through the modem to your ISP, which provides external DNS resolution. Typically, you configure a third-party WAP by accessing a webpage interface and a Wi-Fi adapter card through a dialog box. Refer to the manufacturer’s documentation for details. MORE INFO Internal vs. external resolution If you need to resolve a computer name on your internal network to an IP address (for example, if you entered ping Glasgow in the Command Prompt window), then the DNS service on your WAP or ICS computer provides the IPv4 address that corresponds to the computer name. If, on the other hand, you needed to resolve an FQDN on the Internet (if you entered http://www.contoso.com in your browser, for example), then that FQDN is resolved over the Internet. FQDNs are resolved over the Internet using a DNS server hierarchy and an iterative process. Although it is unlikely that the 70-620 examination will test your knowledge of iterative DNS queries, you will need to know how DNS works over the Internet if you intend to develop your career as a network engineer. For more information, access http://technet2.microsoft.com/WindowsServer /en/library/0bcd97e6-b75d-48ce-83ca-bf470573ebdc1033.mspx?mfr=true. Traditionally, an ICS computer provided DNS, DHCP, and Internet connectivity for a wired SOHO network and a third-party WAP performed the same function for a wireless network. However, many modern computers (both desktop and laptop) include a built-in Wi-Fi adapter card, which means that the computer itself can act as a WAP. Windows Vista provides a wizard that lets you easily configure wireless access for such a computer. The same wizard lets you save wireless settings on a USB flash drive to enable you to join other wireless-enabled computers to your network. If you use this facility, the computer that you configure to provide wireless access is also configured for ICS, so it provides DHCP and DNS services on the SOHO network. Figure 7-7 shows the SOHO network configurations described in this lesson. Lesson 1: Using the Network And Sharing Center to Configure Networking 311 Wi-Fi enabled ICS computer To ISP and internet wireless computers modem To ISP and internet wireless computers modem WAP wired computer(s) ICS computer To ISP and internet modem switch Figure 7-7 Exam Tip SOHO network configurations The 70-620 examination is likely to test the configuration in which a computer running Windows Vista is configured to provide both wireless access and DHCP and DNS services. 312 Chapter 7 Configuring Network Connectivity Setting Up a Network Connection The first computer you install on a wired SOHO network will likely be connected to a modem through a USB or Ethernet connection. It will also have an Ethernet connection to enable computers and other devices to connect to it through a hub. Your ISP will give you instructions about how to establish an Internet connection and will provide a username and password. To connect to the Internet, you access the Network And Sharing Center from Control Panel, click Set Up A Connection Or Network, select Connect To The Internet, and click Next. You then select the method you are using to connect—for example, Broadband PointTo-Point Protocol Over Ethernet (PPPoE)—and enter the name and password that your ISP provided, as shown in Figure 7-8. If you choose to allow other people to use the connection, a UAC dialog box appears. When you click Connect, the wizard configures your Internet connection. Figure 7-8 Providing information from your ISP You can specify a name for your network by opening the Network And Sharing Center and clicking Customize. You then select Public or Private (Private for a SOHO) and type a network name—for example, tailspintoys.com. On the next wizard page you click Close to confirm your settings. The Network And Sharing Center now displays your network connected to the Internet, as shown in Figure 7-9. You can get details about the Sharing And Discovery settings and change a setting if you need to by clicking the arrow beside each setting. Lesson 1: Using the Network And Sharing Center to Configure Networking Figure 7-9 313 The Network And Sharing Center Typically, other computers on a wired SOHO will connect to the Internet through the first computer that you configure on the network. To enable this to happen, you need to configure ICS on that computer. You also enable ICS in the configuration where a computer with a Wi-Fi adapter is providing both ICS and wireless connectivity. To enable ICS, follow these steps: 1. Open the Network And Sharing Center and click Manage Network Connections. 2. Right-click the connection you want to share and click Properties. 3. As prompted, either provide administrator credentials or click Continue in the UAC dialog box. 4. Click the Sharing tab, and then select the Allow Other Network Users To Connect Through This Computer’s Internet Connection check box. NOTE The Sharing tab The Sharing tab is not available if you have only one network connection. You cannot configure ICS unless you have both a connection to the Internet and a connection to other computers on your network. 314 Chapter 7 Configuring Network Connectivity 5. If you want to, you can also select the Allow Other Network Users To Control Or Disable The Shared Internet Connection check box. This is sometimes known as making the connection universal, and it is necessary if you want to determine whether someone else has been making changes to network connection settings. 6. Optionally, you can allow other network users to use services running on your network by clicking Settings and selecting the services you want to allow. When you enable ICS, your LAN connection is configured with a new static IP address (192.168.0.1) and other settings—for example, subnet mask, default gateway, and DNS server address. The static address (192.168.0.1) is used as the default gateway for the subnet—default gateway addresses need to be static. If you connect other computers to your network before you enable ICS, you might need to change their TCP/IP settings, typically by rebooting. As a general rule it is preferable to add other computers to your network after you have configured ICS. To add a computer to a wired network you need only connect it to the network and turn it on. Provided the computer is set to receive its configuration automatically and the computer’s name is not the same as that of another computer already on the network, the computer will join the network and receive its configuration through ICS. If you have changed the default workgroup name (WORKGROUP) on your network, you also need to change this setting on any computer you add. Adding a computer through a wired connection to a hybrid network is the same as adding it to a fully wired network. You simply plug it in and turn it on. By default it should be configured to obtain its IP settings automatically. In this case, however, it obtains them from the WAP (either a third-party WAP or a Wi-Fi–enabled computer configured to provide wireless access and ICS). MORE INFO Setting up a virtual private network (VPN) connection If your business network supports a VPN connection, you might want to connect to the business network from home by using the VPN connection. You also need to be able to advise users you support on how to do this. For more information, search for “Set up a connection to your workplace by using VPN” in Windows Help and Support. Exam Tip The 70-620 examination probably will not ask you how to set up a VPN server. It could, however, test your knowledge of how to connect through a VPN connection. Adding a Wireless Device to a Network If you have a wireless network, you can run the Set Up A Wireless Router Or Access Point Wizard on one computer that is already on your network and save network settings to a USB flash drive. This is the same wizard that you would use to configure a computer with a Wi-Fi adapter Lesson 1: Using the Network And Sharing Center to Configure Networking 315 to provide wireless access for a network. The steps you follow are almost identical except that in one case you are configuring settings to create a file on a USB drive that enables other computers to connect to a configured wireless network. In the other case you are configuring the actual wireless settings. You can add a wireless-enabled computer to your network by plugging the USB flash drive into that computer and clicking Wireless Network Setup Wizard in the AutoPlay dialog box. You save wireless settings to a USB drive and add a wireless-enabled computer to your network in the practice session later in this lesson. If you are setting up a WAP on a computer with a WiFi interface that is running Windows Vista, you follow much the same procedure except you do not specify saving the settings to a USB flash drive. (You also need to configure ICS on that computer.) However, you can save settings to a flash drive if your Windows Vista computer is Wi-Fi enabled and provides wireless access itself or if it is not Wi-Fi enabled but is connected to a third-party WAP. Saving settings to a USB flash drive is therefore the more universal procedure, which is why it has been chosen for the practice session. Alternatively, you can manually add a wireless computer running Windows Vista to your network by clicking Connect To on the Start menu, choosing the wireless network from the list that appears, and then clicking Connect. You then type the network security key or passphrase (if prompted) and click OK. NOTE Network security key By default, a WAP is set to permit open access by any wireless-enabled computer within its range. You can set up your WAP to require a security key and ensure that any user who wants to add a computer to the network needs to provide a passphrase. Refer to the manufacturer’s instructions for details. For more information about wireless network security, search for “Set up security for your wireless network” in Windows Help and Support. Quick Check ■ You are adding a new computer to a wired network that connects to the Internet through a cable modem attached to one of your computers by a USB cable. The new computer is configured to obtain its IP configuration automatically. When you turn the new computer on, it is configured with an IP address, a subnet mask, and IP addresses for its default gateway and DNS server. Where does it get this information? Quick Check Answer ■ From the computer attached to the modem, which is configured to run ICS To add a wireless device other than a computer to a network, you need to follow the manufacturer’s instructions that came with the device. You might be able to add the device using a USB flash drive. If the device is a printer, you might need to enable printer sharing so that other 316 Chapter 7 Configuring Network Connectivity computers on the network can use it. If you want to add a Bluetooth enabled device to your network, you need a Bluetooth network adapter. MORE INFO Bluetooth For more information about Bluetooth, search for “Bluetooth” in Windows Help and Support. Wireless Networks In a wireless network the computers are connected by radio signals instead of wires or cables. Advantages of wireless networks include mobility and easy physical installation (you do not need to run cables under the floor). Disadvantages include a slower connection (typically) than a wired network and interference from other wireless devices, such as cordless phones. Currently three types of wireless network technologies are in common use: ■ 802.11b Up to 11 megabits per second (Mbps); good signal range; low cost. This technology allows fewer simultaneous users than the other two options and uses the 2.4 gigahertz (GHz) frequency. This frequency is prone to interference from microwave ovens, cordless phones, and other appliances. ■ 802.11a Up to 54 Mbps; more simultaneous users than 802.11b but a smaller signal range; expensive. This option provides a fast transmission speed and uses the 5 GHz frequency, which limits interference from other devices. However, its signal is more easily obstructed by walls and other obstacles and it is not compatible with 802.11b network adapters, routers, and access points. ■ 802.11g Up to 54 Mbps (under optimal conditions); more simultaneous users than 802.11b; very good signal range; not easily obstructed. This option is compatible with 802.11b network adapters, routers, and access points, but it uses the 2.4 GHz frequency and has the same interference problems as 802.11b. It is also more expensive than 802.11b. 802.11b is adequate for most home and many small office applications. If, however, your network carries a high volume of streaming media (video or music) traffic or if interference is a major problem, you might consider 802.11a. If you already have 802.11b devices on your network but require high-speed transmission between specified network points, you might consider 802.11g. Most modern WAPs on sale from computer equipment retailers are now 802.11g. If you have more than one wireless network adapter in your computer or if your adapter uses more than one standard, you can specify which adapter or standard to use for each network connection. Lesson 1: Using the Network And Sharing Center to Configure Networking NOTE 317 802.11n The 802.11n standard is still in draft format and cannot currently be described as being “in common use.” However, a number of vendors are manufacturing equipment using the current draft 802.11n standard. Most 802.11n devices are compatible with 802.11b and 802.11g. Exam Tip Several 802.11 standards exist in addition to 802.11a, 802.11b, and 802.11c. However, the standards described in this lesson are those in common use. If you see any other standard (for example, 802.11d) given as a possible answer in the examination, that answer is almost certainly wrong. Whether this statement should include 802.11n is debatable because it is possible to buy an adapter that conforms to the draft 802.11n standard. Managing Network Connections You can view a list of all the connection interfaces (wired and wireless) on a computer by opening the Network And Sharing Center and clicking Manage Network Connections. This opens the Network Connections folder that stores all the connections that enable your computer to connect to the Internet, a network, or another computer. When you install a network adapter in your computer, Windows creates a connection for it in the Network Connections folder. A local area connection is created for an Ethernet network adapter (or any other hard-wired network adapter), and a wireless network connection is created for a wireless network adapter. You can right-click any network connection and select Status. If you click Details in the Local Area Connection Status dialog box, you access the Network Connection Details dialog box, shown in Figure 7-10. The information in the Network Connection Details dialog box for any connection on your computer will almost certainly differ from that shown in Figure 7-10, but it is instructive to look at the information in that figure. In this case, the workstation is on a small business network that connects to another (probably larger) network that provides DNS, WINS, and DHCP services. It is likely that workstations on the small business network access other networks, including the Internet, through the second network. The computer is on the 10.16.10.0 subnet, with an IP address of 10.16.10.143. This subnet accesses other subnets, in particular the 10.16.10.30 subnet, through a gateway with an IP address of 10.16.10.1. The 10.16.30.0 subnet contains a server with the IP address 10.16.30.10 that provides DHCP, DNS, and WINS services. (The router is configured to pass DHCP broadcasts between the networks.) A server with the IP address 10.16.30.11 also provides WINS and DNS services. Figure 7-11 shows this network structure. This type of setup is common in a business or educational environment, but you are unlikely to come across it on a home network. 318 Chapter 7 Configuring Network Connectivity Figure 7-10 The Network Connection Details dialog box 10.16.30.0 subnet default gateway DHCP, DNS, and WINS servers default gateway To internet 10.16.10.0 subnet 10.16.10.143 Figure 7-11 Typical network structure in a business or educational environment Lesson 1: Using the Network And Sharing Center to Configure Networking 319 On a wired home network with ICS enabled, a workstation typically has an address on the 192.168.0.0 network with its default gateway 192.168.0.1. A WAP is typically not configured with the 192.168.0.1 address but might instead have, for example, the IP address 192.168.123.254. This is then the default gateway for the computers and other devices on the network. Whatever the settings on your network are, you should take a note of them when everything is working correctly. This information is invaluable if something goes wrong. Figure 7-10 also shows that NetBIOS over TCP/IP is enabled. Some services and applications use NetBIOS names rather than DNS hostnames, and enabling this setting allows these applications to work. The Physical Address value in Figure 7-10 is the MAC address of the NIC. Exam Tip The 70-620 examination is most unlikely to contain questions related to NetBIOS over TCP/IP or MAC addresses. This book defines them but does not discuss them in depth. Clicking Close in the Network Connection Details information box returns you to the Local Area Connection Status dialog box. Clicking Properties and supplying administrator credentials or clicking Continue in the UAC dialog box accesses the Local Area Connections Properties dialog box. From this dialog box you can enable or disable the items shown or install more items (client services, server services, or protocols) by clicking Install. Typically, the Local Area Connection Status dialog box (for both wired and wireless connections) might contain the following items: ■ Client For Microsoft Networks Enables the computer to access resources on a Microsoft network. ■ ■ ■ ■ ■ ■ Quality Of Service (QoS) Packet Scheduler Provides traffic control. This can be significant if you have high-bandwidth traffic, such as video streaming, on your network. File And Printer Sharing for Microsoft Networks Enables other computers to access resources on your computer in a Microsoft network (and other networks). Internet Protocol Version 6 (TCP/IPv6) IPv6 configuration. Internet Protocol Version 4 (TCP/IPv4) IPv4 configuration. Link-Layer Topology Discovery Mapper Input/Output (I/O) Driver Discovers and locates other computers, devices, and network infrastructure components on the network and determines network bandwidth. Link-Layer Topology Discovery Mapper Responder Allows the computer to be discovered and located on the network. If an item is configurable, selecting the item activates the Properties button, and you can click this to configure the item’s properties. You can also configure the adapter itself (for example, update the driver) by clicking Configure in the Local Area Connections Properties dialog box.