Networking: A Beginner’s Guide Fifth Edition- P17 doc

62 Networking: A Beginner’s Guide All of these components are available separately, just as you would purchase them for a business. You can also purchase home networking kits, which include all of the components that you need, along with instructions for setting up the home network. TIP Look for recent reviews of products for home networking and use those reviews to help you decide which product meets your needs. Many computer magazines have up-to-date product reviews, including reviews of home-oriented products. Check your local library or the magazine rack at your local bookstore. Phoneline and Powerline Networking Options A point made in the preceding section bears repeating: The hardest part of installing a home network is the wiring. Most people aren’t qualified to install network cabling, nor do they want to start making holes in their walls and trying to figure out how to route cabling through their house (or under their house). Many companies have come out with alternative network options that eliminate the need for installing network cabling, including phoneline and powerline networks. Phoneline Networks It’s possible to use a home’s existing telephone wiring to provide a network connection between computers in a home. This option becomes attractive if there are telephone connections near each computer. Intel, 3Com, D-Link, and other companies offer phoneline network kits for the home. A resource available on the Internet for phoneline networking is http://www .homepna.org. Powerline Networks Some companies offer hardware that lets you network computers through a home’s existing power wiring. The network equipment transmits its information through the power wiring, and all that’s needed is to plug a special adapter into an available outlet near each computer. Be aware that powerline networks are subject to electrical noise from various types of equipment in the home. (One reviewer, in fact, had his powerline network crash every time his refrigerator’s compressor came on.) However, if this approach makes sense in your home, give it a try. Just be sure to save your receipts and ensure you can return the equipment if it doesn’t work in your home. You can learn more about powerline networking at http://www.homeplug.com. Wireless Networking By far, the most popular home networking option is to use wireless connections. Quite a number of companies—including NETGEAR, D-Link, and Linksys—offer wireless home networking equipment. 63 Chapter 5: Home Networking When using the latest technology, wireless networks run at a pretty fast clip. They start at 11 Mbps (more than adequate for home use), and many variants go up to 54 Mbps. However, different factors in your home may limit the wireless network’s speed or functionality. For example, an appliance may be the source of electrical interference, or something in the walls might limit the signal strength between rooms or floors. Make sure that you can return or exchange the equipment if it doesn’t work properly in your home. Wireless Standards Three basic wireless standards are in wide use: 802.11b, 802.11a, and 802.11g. It’s counterintuitive, but in this particular case, 802.11a is a more advanced and faster standard than 802.11b. 802.11g is essentially an upgrade to 802.11b and uses the same frequencies to transmit data. The 802.11g standard is presently leading the market, and many good and relatively inexpensive solutions use this standard. You can even purchase units that combine an 802.11g wireless access point (WAP), which is sort of like a wireless hub, with a router intended to share a home’s high-bandwidth Internet connection among multiple computers. The nice thing about such combination units is that you don’t need to pay more for Internet service for multiple computers, since the router makes it appear as if only one computer were on the connection. NOTE A new wireless Ethernet standard called 802.11n is starting to emerge. It promises higher speeds and potentially better range than the existing standards. This is still a draft standard, expected to be finalized around the end of 2009. Products that use the draft standard are currently available, but if there are changes to the draft 802.11n standard in its final release, these products may not work properly with devices based on the final version. Wireless Network Caveats Before you install a wireless network, you should be aware of the following: N The predominant standards operate at different data speeds. 802.11b operates at 11 Mbps; 802.11g and 802.11a both operate at up to 54 Mbps. N The particulars of the home and other installed equipment may interfere with a wireless network. This is most pronounced with 802.11b and 802.11g, which operate at 2.4 GHz—the same frequency as many portable telephones and also near the frequency where microwave ovens operate. For example, when I set up an 802.11b network at my home several years ago, I kept getting dropped connections, and I couldn’t use my portable phone anywhere near the wireless network connections because it caused audible interference. 802.11a operates at 5 GHz, which may be less subject to interference in a home that has interference in the 802.11b/g frequency. 64 Networking: A Beginner’s Guide N A wireless network potentially exposes you to security risks. People with wirelenss network cards installed in their notebook computers can cruise around looking for free connections. More likely is that your neighbors may be able to “hitch a free ride” on your Internet connection through your home network if you don’t secure it when you install it (this is more common than you might think). N This area is continuing to evolve very rapidly, and a solution purchased today may not be compatible with equivalent hardware available in a couple of years. Chapter Summary In this chapter, you learned a little about the rapidly changing field of home networking. In many cases, you can build a home network using inexpensive, off-the- shelf parts designed for small business networks. The main problem with this approach is cabling the house, although if all of the computers are in one room, this won’t be too difficult. For more complicated setups, or to have more flexibility, consider using alternative networking technologies. NOTE For more on setting up a home network, see Home Networking Survival Guide by David Strom (McGraw-Hill/Professional, 2001). Generally, most people should first investigate using wireless home networking equipment. This equipment works well in many homes, is inexpensive, and is well supported for this purpose. In certain cases, it may be appropriate to use standard wired networking equipment or even phoneline or powerline networking equipment. As always, assess your needs carefully and make sure that you can exchange or return any home network equipment if it doesn’t work properly in your home. 65 Chapter 6 Understanding Network Hardware 66 Networking: A Beginner’s Guide I f network wiring constitutes the nervous system of a network, then the devices discussed in this chapter represent the various organs. These network devices— repeaters, routers, hubs, and such—are responsible for moving data from one network cable to another. Each device has different properties and uses. A good network design uses the correct device for each of the various jobs the network must fulfill. In this chapter, you learn about essential networking hardware, including the following: N Repeaters N Hubs and concentrators N Switches N Bridges N Routers N Gateways N Firewalls N Short-haul modems for short interbuilding connections It is essential that you understand these basic components that go into building a network, as well as the job each performs. Directing Network Traffic The critical test of any network design is its capability to direct network traffic from one node to another node. You must connect the network’s various devices in a configuration that enables the network to pass signals among the devices as efficiently as possible, taking into account the type of network and the different connectivity requirements for the network. The following are the basic connection devices: N Repeaters These extend the distance that network traffic can travel over a particular type of network media. N Hubs (concentrators) These devices are used to connect nodes to one another when you use a star topology, such as 100Base-T. N Bridges These are basically intelligent repeaters that direct traffic from one segment to another only when the traffic is destined for the other segment. N Routers These can intelligently route network traffic in a variety of important ways. N Switches These form fast point-to-point connections for all the devices connected to them. Connections from one port on a switch to another port are made on an as-needed basis and are not broadcast to ports that aren’t involved in the traffic. By limiting the connections made, switches help eliminate traffic collisions caused by noncommunicating segments. . equipment transmits its information through the power wiring, and all that’s needed is to plug a special adapter into an available outlet near each computer. Be aware that powerline networks are subject. 802.1 1a, and 802.11g. It’s counterintuitive, but in this particular case, 802.1 1a is a more advanced and faster standard than 802.11b. 802.11g is essentially an upgrade to 802.11b and uses the same. 62 Networking: A Beginner’s Guide All of these components are available separately, just as you would purchase them for a business. You can also purchase home networking kits, which include all