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components behave in a similar manner as they would if used from a UNIX-based computer. Also included is the Interix Software Development Kit (SDK), which supports over 1900 UNIX application programming interfaces (APIs).

tip For more information about Microsoft Services for UNIX and Windows XP, check out the Microsoft Windows Services for UNIX Web site at www.microsoft.com/windows/ sfu/default.asp.

Requirements for SFU 3.0

To install SFU 3.0, your computer must meet the following minimum requirements:

●16 MB of RAM.

●19 MB of available hard disk space. 184 MB is required for a complete installation.

●CD-ROM drive.

●Microsoft Internet Explorer version 5.5 or later.

●Network adapter.

In addition to the minimum requirements, there are several Microsoft recommendations for any computer running SFU. There are also some limitations associated with SFU 3.0. The following list outlines recommendations that should be met to ensure maximum performance as well as limitations to keep in mind:

●If Windows 2000 is used to host SFU 3.0, Service Pack 2 should be installed, although it is not required.

●Gateway for NFS requires a server edition of Windows.

●SFU 3.0 cannot be used with Windows NT 4.0 Terminal Services Edition.

●Client for Network File Systems (NFS) and Gateway for NFS cannot be simultaneously installed on the same computer.

●Server for NIS must be installed on a Windows 2000 domain controller.

Installing Services for UNIX

To install SFU, you need the SFU installation CD and a computer running Windows XP, Windows 2000, or Windows NT 4.0. After the install process is completed, your SFU installation will be ready for use.

Connecting Windows and Mac OS X Using Samba

Because Mac OS X is based on a distribution of UNIX, it offers some of the interoperability features possible with other UNIX systems. If a Mac OS X system running Samba is present on the network, you can connect to the server using its Universal Naming Convention (UNC) path, such as \\macosx_server\sharename, where macosx_server is the NetBIOS name used by Samba on the Macintosh, and sharename is the name of the SMB resource being shared. In addition, Samba allows the Mac OS X systems to connect with SMB resources shared by Windows (or other Samba) systems.

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Wireless

Networking

The buzz about wireless networking has been around for years, but only recently has wireless networking begun to become a reality for corporate networks and for home and small office networks. In fact, if you browse your local computer store, you are likely to find many different brands of wireless access points as well as wireless network adapters for desktop computers and laptops.

What does all this mean for you? Wireless networking has finally arrived; it works well, it offers different levels of security, and it’s cost effective, although sometimes more expensive than traditional wired networking. If you are currently planning a home or small office network, a wireless network is certainly a viable alternative. In an existing corporate network, adding wireless functionality to the network might solve a number of problems and give mobile network users added flexibility.

In this chapter, you’ll learn about wireless networking. You’ll learn how it works, your security options, the network designs you can use, and whether wireless networking is right for you.

Getting to Know

Wireless Networking

Microsoft Windows XP helps make configuring a wireless network simple. Before trekking off to the computer store to buy the components needed, however, you should read this section to gain an understanding of wireless networking, the kinds of wireless networks supported by Windows XP, and whether you can benefit from wireless networking.

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Why Wireless Networks Are Important

Wireless networks provide freedom—that is the basis for their appeal. In a world of mobile employees, networking needs to be just as mobile, and that mobility goal has evolved into the wireless technologies available today. Here are just a few examples of some common uses for wireless networking.

●In a home network, you can use a laptop computer with a wireless network adapter and travel from room to room, retaining network connectivity. Combined with Internet Connection Sharing (ICS), you can have your desktop computer provide an Internet link, and your wireless computer can access the Internet through the ICS host computer. This not only allows you to access shared information available on the desktop computer (such as folders and printers), but also allows you to browse the Internet from any room in your house or even in your yard—anywhere within the usable range of your wireless equipment! The coverage area for your wireless network depends on many factors, such as the locations of your wireless equipment, how well the signal can travel through various obstructions, and any interference on the frequencies used by the wireless equipment.

●In a home network, wireless networking can help reduce computer costs and give you more flexibility. For example, your family room might have two computers networked together. One computer provides Internet access to your home network. Your children use the Internet for homework as well as game playing on a regular basis, and using the computer in the family room is sometimes inconvenient for you. You could add a wireless adapter to a laptop computer and do your computing in the quiet and privacy of another room while your children do their homework or play games in the family room.

●You could have a home network that is completely wireless, or you could have a residential gateway with an integrated wireless hub, known as a wireless access point, connected to a DSL connection for Internet access. Each computer in your house can be outfitted with a wireless NIC, and the network will work just like a wired network, but you’ll have the added freedom of placing each computer in any location you want without worrying about running cables. Additionally, should you need to rearrange your network at some point in the future, the computers can be easily moved with no network disruption.

●In a small office environment, wireless networking provides many of the same features that a home network user would find attractive; however, in an office setting, the key benefit provided by wireless networking is its flexibility. For example, you might work in a small office building and your job

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duties might include attending meetings in various rooms throughout the building, taking notes at each meeting using your laptop. Traditionally, you might use a laptop for such purposes, but you would have to disconnect from the network each time you moved and reconnect with a cable to a jack in the wall. The cabling can be clumsy and aggravating, if such jacks are available at all. Plus, you must disconnect and log back on to the network each time. Using a wireless network, you can move about as needed without concern for the locations of network jacks and even keep continuously connected if you like.

●In corporate networks, wireless networks are often used as a workaround for particular access problems. For example, they might be used in a portion of an office building where cables cannot be placed. Wireless connections can easily solve these problems and provide the required network connectivity.

●If your company or site hosts network or Internet access for outside visitors, you can even configure wireless networking to provide network access to visiting clients or business partners (with appropriate security of course). By equipping a laptop with a wireless network adapter, Windows XP can automatically configure its wireless adapter for access to the wireless network where available, giving your clients and partners instant access to the Internet when they arrive at your site.

●Many public areas, including airports, conference centers, and hotels, now provide wireless Internet access on open networks. These areas, called hot spots, give mobile users access to the Internet on the users’ own computers. Because Windows XP can automatically configure access to the wireless network, you can essentially step off an airplane, turn on your laptop, and access the Internet. After you arrive and check in to your hotel, you can resume your Internet connection and continue to access it while attending a conference. If you have a VPN or other remote access connection via the Internet to your private network, you can access your personal documents as well.

Types of Wireless Networking

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port on your computer. Additionally, laptops and PDAs can connect to a desktop computer for data transfer. Infrared is a great solution for device-to-PC connectivity, but in terms of a LAN solution, infrared is not the preferred method. In many cases, however, infrared can provide solutions to unique problems. In addition to not being practical for a LAN, infrared is restricted to computers and devices in one physical area, such as a single room.

●Wireless Personal Area Networks (WPANs). A WPAN is a personal area network, which means it resides in one generalized space, such as a room. Quite literally, a personal area is the area surrounding a person. WPANs are useful for wireless network computing in one location or wireless networking between PDAs, cellular phones, laptop computers, and so on. WPANs can use infrared connections for objects that are very close (for example, objects sitting on the same table), or they can use radio frequency technologies such as Bluetooth, which can communicate up to 30 feet. The IEEE (its full name is the Institute of Electrical and Electronics Engineers) has established a working group (IEEE 802.15) for the development of WPAN standards. The 802.15 standard seeks ease of interoperability, simple designs, and compatibility with other wireless networks. You can learn more about the standard at www.standards.ieee.org.

Keeping the Standards Straight

As you investigate different wireless technologies and standards, it’s easy to become confused by the many standards and numbers. Keep in mind that the IEEE’s job is to create standardization for different kinds of networks that use the same technology. The end result is that different devices can work together on the same network. Using the 802.15 standards, devices such as laptops, PDAs, cellular phones, and other portable devices can implement the Bluetooth specification, and they can all communicate and work together on the same WPAN. You’ll see different IEEE standards apply to different kinds of wireless networks (as well as wired networks), and each time you read about an IEEE standard, you’ll know that standards for communication are in place or being developed that will make the technology a viable means of networking for you.

●Wireless Local Area Networks (WLANs). A WLAN is a wireless network located in a home, office building, school, or other such structure. A WLAN can also exist as a separate network in addition to a wired LAN if desired. The WLAN uses radio frequencies to enable all computers within the

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WLAN to communicate with each other. The IEEE 802.11 standard for WLANs defines speeds of 1 and 2 Mbps. Clearly, the 802.11 standard is rather slow. However, the new IEEE standard for WLAN networking is 802.11b, which defines transfer rates of up to 11 Mbps using the 2.4 GHz Industrial, Scientific, and Medical (ISM) frequency band. The 802.11b standard is currently the most popular standard, giving you speeds comparable to a typical Ethernet network. IEEE 802.11a, a newer standard that provides bit rates of up to 54 Mbps using the 5 GHz frequency band, is now available as well.

●Wireless Metropolitan Area Networks (WMANs). WMANs allow wireless communications within a single metropolitan area. For example, a WMAN in New York City could let a company connect wirelessly to its three offices located around the city. The IEEE 802.16 standard, which defines the technologies that can be used in WMANs, is still under development. WMANs can use radio waves, infrared light, or even laser connections to transfer data between locations.

●Wireless Wide Area Networks (WWANs). A WWAN connects WLANs that are separated over wide geographic areas. For example, if your company has offices in New York, Seattle, and Dallas, a WWAN could be used to wirelessly connect the different WAN network segments. WWAN technologies involve the use of satellite communications maintained by service providers and also use the same technologies as cellular phones and wireless PDAs. Common technologies include Global System for Mobile Communications (GSM), Cellular Digital Packet Data (CDPD), and Code Division Multiple Access (CDMA).

Wireless Networks Supported by Windows XP

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How Infrared and Wi-Fi Work

Windows XP is optimized for two kinds of wireless networking—infrared and Wi-Fi. Each network type has its own advantages and challenges, and is typically used for different purposes. The following sections examine how infrared and Wi-Fi networking work in Windows XP.

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Wired and Wireless LANs Bridged Using a Wireless Access Point

Ethernet clients

Wireless access point

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