Setting Up a Small Office or Home Network : Configuring Your Network Hardware

• Network adapters Each computer needs an adapter to communicate with the other computers on the network. (An adapter is sometimes called a network interface card, or NIC.) Network adapters can be internal or external. Internal adapters are often incorporated directly onto the motherboard of a desktop or notebook PC, or they can be installed in a PCI slot on a desktop PC or a mini-PCI slot hidden within the guts of a notebook computer. External adapters are typically connected to a USB port. Most wired network adapters conform to the Ethernet standard. Wireless adapters conform to one of several 802.11 (Wi-Fi) standards.

• A central connection point Use a hub or switch to connect the computers in an Ethernet network. This function is sometimes integrated in a router or residential gateway. On a wireless network, a wireless access point handles these duties.

  In this article, we sometimes use the term hub in its generic sense to refer to a central connection point for networks that use a star-bus topology, such as Ethernet. However, a hub (using its more precise definition) is just one of several types of connection points commonly used in home and small office networks:

  • Hub A hub is the simplest and slowest of these devices, all of which have several jacks (called ports) into which you can plug cables attached to computers and other network devices. In a hub (which is sometimes called a repeater), data that is received on one port is broadcast to all its ports, which produces a lot of unnecessary network traffic.

  • Switch By keeping track of the unique Media Access Control (MAC) address for each connected device, a switch is able to receive data and in turn send it only to the port to which the destination device is attached. A switch is faster and more secure than a hub.

  • Router Unlike hubs and switches, which are used to connect computers on a single network, a router is typically used to connect two or more networks. In a small network, a router typically is used to connect the local area network to the network at an internet service provider (which, in turn, uses routers to connect to the internet backbone).

    A residential gateway is a router that typically adds Network Address Translation (NAT) and Dynamic Host Configuration Protocol (DHCP) capabilities. (NAT enables multiple computers on a network to share a single public IP address. DHCP is a system for assigning an IP address to each computer on a network.) In addition, many residential gateways include a stateful packet inspection fire-wall and other security features.

    A wireless gateway adds wireless capability to a residential gateway, thereby enabling connections to computers with Wi-Fi adapters as well as computers with wired adapters. To add wireless capability to a network centered around a nonwireless residential gateway, use a wireless access point.

• Cables On an Ethernet network, you connect each network adapter to the hub using an eight-wire Category 5, Category 5e, or Category 6 patch cable with RJ-45 connectors on each end. (Cat 5 is designed for Fast Ethernet, with speeds up to 100 Mbps, whereas Cat 5e and Cat 6 cable are designed for Gigabit Ethernet, with speeds up to 1 Gbps.) HomePNA networks connect to an existing telephone jack with a standard telephone connector (RJ-11). Power-line networks typically use Cat 5 cables to connect computers to adapters that plug into a power outlet. By definition, wireless networks require no cables, except typically between the wireless access point and the internet.

Although it's not required, most networks also include one additional hardware component: a modem or other device to connect your network to the internet.

1. Wired or Wireless?

When setting up a network in a home or office for use with Windows 7, you can choose from several technologies, including

• Ethernet This popular networking standard, developed in the mid-1970s, has stood the test of time. The original Ethernet standard (also known as 10Base-T) is capable of transferring data at maximum speeds of 10 megabits per second. The Fast Ethernet standard (also known as 100Base-T) can transfer data at 100 megabits per second and is currently the mainstream system used in most homes and small office networks. A newer standard called Gigabit Ethernet allows data transfers at 1 gigabit (1,000 megabits) per second. In an office or home that is wired for Ethernet, you can plug your network adapter into a wall jack and install a hub at a central location called a patch panel. In a home or office without structured wiring, you'll need to plug directly into a hub.

• Wireless In recent years, wireless networking technology has enjoyed an explosion in popularity, thanks to its convenience, steadily decreasing prices, and ubiquity. Wireless connections are now available in many hotels, trains, buses, ferries, and airplanes in addition to the more traditional hotspot locations such as cafés and libraries.

  Although wireless local area networks (WLANs) were originally developed for use with notebook computers, they are increasingly popular with desktop computer users, especially in homes and offices where it is impractical or physically impossible to run network cables. The most popular wireless networks use one of several variants of the IEEE (Institute of Electrical and Electronics Engineers) 802.11 standard, also known as Wi-Fi. Using base stations and network adapters with small antennas, Wi-Fi networks using the 802.11g standard transfer data at a maximum rate of 54 megabits per second using radio frequencies in the 2.4 GHz range. (Some manufacturers of wireless networking equipment have pushed the standard with proprietary variations that approximately double the speed.) Currently the most popular, 802.11g-based networks have largely supplanted those based on an earlier standard, 802.11b, which offers a maximum speed of 11 megabits per second. Nipping at the heels of 802.11g is 802.11n, which offers approximately a tenfold improvement in speed as well as significantly greater range.
  

  Most 802.11g hardware works with 802.11b networks as well. Likewise, most 802.11n (draft) hardware is backward compatible with 802.11g and 802.11b devices. (Note, however, that all traffic on your network runs at the speed of the slowest wireless standard in use; if you've just bought an 802.11n router, you might want to pony up a few dollars more to replace your old 802.11b and g network adapters.)

  Another Wi-Fi standard you might encounter is 802.11a, which can reach maximum speeds of 54 Gbps. It broadcasts in a different frequency range (5 GHz), and is therefore incompatible with 802.11b, 802.11g, and 802.11n equipment, except for specialized dual-band and multiband gear.

  A number of other wireless network standards promulgated by the IEEE's 802.11 Working Group promise benefits such as better security. Be aware that, despite the confusingly similar names, network equipment using one of the wireless standards is generally compatible only with other equipment using the exact same standard. 

• Phone line Networks that comply with early versions of the HomePNA standard operate at speeds of roughly 10 megabits per second; the HomePNA 3 standard works at speeds of up to 128 megabits per second. HomePNA networks don't require a central connection point such as a router or hub; instead, they employ a daisy-chain topology in which all network adapters communicate directly by plugging into existing telephone jacks and transmitting data on the same wires that carry telephone and fax signals, without interfering with those communications. 

• Power line Another technology that uses existing wiring communicates over power lines. Two trade associations—HomePlug Powerline Alliance and Universal Powerline Association—have developed standards (which are not compatible with each other) for power-line communications, and each one can be found on devices from a small number of manufacturers. Speeds up to 200 megabits per second are claimed. You can find more information at the HomePlug Powerline Alliance (homeplug.org) and Universal Powerline Association (upaplc.org).

Ethernet and wireless are the dominant networking technologies in homes and offices. The availability of inexpensive wireless network gear has relegated phone-line and power-line technologies to niche status; they are most attractive in older homes where adding network cable is impossible and wireless signals are impractical because of distance, building materials, or interference.

In many homes and offices, it's impractical to rely exclusively on one type of network. For example, it might not be feasible to run cables to every location where you want a computer. Yet, a wireless network might not be adequate because the signal can't reach all locations due to the number and type of walls and floors that separate computers. In such a case, you can install two or more networks of different types and use a router or a bridge to connect the disparate networks.

2. Installing and Configuring a Network Adapter

On most systems, you don't need to take any special configuration steps to set up a network adapter, regardless of whether it's for an Ethernet, wireless, HomePNA, or power-line adapter. The Plug and Play code in Windows handles all the work of installing drivers. If you install an internal adapter and Windows includes a signed driver for that adapter, the driver should be installed automatically when Windows detects the adapter. (If Windows cannot find a built-in driver, you'll be prompted to supply the location of the driver files.) For an external adapter connected to a USB or IEEE 1394 port, the driver installs in the same way as one for an internal adapter, and thereafter it loads and unloads dynamically when you attach or remove the adapter.

3. Making Connections

On a standard Ethernet network, all computers must be connected via one or more routers, switches, or hubs.

If you're going to connect your network to a broadband internet service, you should use a router or residential gateway as the primary hub. Most such products designed for use in homes and small offices combine a router and hub; in this type of device, you connect your external DSL or cable modem to the internet connector (often labeled as wide area network, or WAN) on the router and then connect each computer on the network to a port on the local area network (LAN) side.

If you use a dial-up connection for internet service, you can use any type of hub to connect your computers.

On wireless networks, a wireless access point typically serves as a hub.

You must be able to run a cable from the hub to each computer on your network. It's not always feasible to make a direct connection from each computer or other networked device to the central hub. (Furthermore, the central hub might not have enough ports to connect all devices.) To make additional connections in an Ethernet network, use another hub or switch.

Figure 1 shows a schematic diagram of a typical network in a home or small business. This network includes both wired and wireless segments.