Home Networking

Introduction

If you own multiple PCs, you have probably thought about how great it would be if your computers could talk to each other. With your computers connected, you could:

Share a single printer between computers
Share a single Internet connection among all the computers in your home
Access shared files such as photographs, MP3s, spreadsheets and documents on any computer in the house
Play games that allow multiple users at different computers
Send the output of a device like a DVD player or Webcam to your other computer(s)

In this reading, we'll look at the different methods you can use to create a home network. At the moment, wireless networking appears to be the easiest and one of the least expensive options. You can buy an 802.11b or 802.11g access point, connect it to your cable modem or DSL modem in a few minutes, and have all your computers talking on a network very quickly. Keep reading for more information on wireless networking and other home networking options.

How to Connect
There are many ways to connect your home computers:

Wire your house with data cables by hiding all the network cable in the walls
Run cables across the floor between computers in the same room
Install some form of wireless networking
Link your computers through your power lines
Link your computers through your phone lines
Walk diskettes and CDs back and forth (the most inexpensive, and inconvenient way)

Each of these methods has it's advantages and disadvantages, but all require you to configure your computer to share printers, files, and an internet connection (with the exception of walking disks and CDs back and forth). You would also need to set up some kind of security system to keep your information protected. The configuring process of setting up a home network requires that you choose which system of networking would work best for you. The four choices are Ethernet, phone-line-based networking, power-line-based networking, and wireless. Once you have made that decision, you need to buy the hardware required to install that system, and then configure your computers so that each computer is talking to the others correctly.

Hardware
There are a number of hardware components necessary to create a home network. Not all of them will be used in one network, and each component is useful in different network configurations. The following is a list of hardware components necessary to build a network, and a description of how they work.

Routers are devices that forward data packets along networks. A router is connected to at least two networks, commonly two LANs or WANs or a LAN and its ISP's network. Routers are located at gateways, the places where two or more networks connect. Routers use configuration tables to determine the best path for forwarding the packets, and they use protocols such as ICMP to communicate with each other and configure the best route between any two hosts. A router has two separate, but related, jobs: it makes sure that information does not go where it's not needed (crucial to keep information from clogging connections of other users), and it sees that information gets to its destination.

Hubs are common connection points for devices in a network. Hubs are commonly used to connect segments of a LAN. A hub contains multiple ports to which clients are connected directly, and one or more ports that can be used to connect the hub to the backbone or to other active network components. When a packet arrives at one port, it is copied to the other ports so that all segments of the LAN can see all packets. Another type of hub, called a switching hub, actually reads the destination address of each packet and then forwards the packet to the correct port. Conventional hubs, also known as passive hubs, simply rebroadcast every packet to every port. Since switching hubs forward each packet only to the required port, they provide much better performance.

Network Interface Cards, often abbreviated as NIC, are expansion boards you insert into a computer so the computer can be connected to a network. Most NICs are designed for a particular type of network, protocol, and media, although some can serve multiple networks.

Transceivers, short for transmitter-receiver, are devices that both transmit and receive analog or digital signals. When speaking of a wireless network, transceivers are also called access points. The term is used most frequently to describe the component in local-area networks (LANs) that actually applies signals onto the network wire and detects signals passing through the wire. For many LANs, the transceiver is built into the network interface card (NIC). Some types of networks, however, require an external transceiver. In Ethernet networks, a transceiver is also called a Medium Access Unit (MAU).

A firewall (technically software) is a set of related programs, located at a network gateway server, that protects the resources of a private network from users from other networks. Basically, a firewall, working closely with a router program, examines each network packet to determine whether to forward it toward its destination. A firewall also includes or works with a proxy server that makes network requests on behalf of workstation users. A firewall is often installed in a specially designated computer separate from the rest of the network so that no incoming request can get directly at private network resources. There are a number of firewall screening methods. A simple one is to screen requests to make sure they come from acceptable (previously identified) domain name and Internet Protocol addresses. For mobile users, firewalls allow remote access in to the private network by the use of secure logon procedures and authentication certificates.

Now that you're familiar with what hardware is used when building a network, you are ready to read about how to create the four different types of home networks.

Ethernet

Ethernet is available in two speeds: 10 megabits per second (Mbps) and 100 Mbps. Most NICs are capable of operating at either speed, but you should check to be sure before purchasing. The difference in cost between the two speeds is minimal. A 100-Mbps card costs about $15 to $40, and a 10/100-Mbps card costs about $25 to $50.

There are two different ways to connect Ethernet cards: coax and Cat 5 cabling. Coax was once the more popular of the two, but today just about everyone uses Cat 5 because it is easier to configure. Cat 5 has a cable that looks a lot like a telephone cable. You run one cable to each computer, and each cable connects to a hub at the other end. A basic hub for a home network is a small box that typically costs from $25 to $50 (depending on its speed and how many connections it can support).

**Figure 1: Hub**

The hub takes the signal from each computer and sends it to all of the other computers in your home. Hubs come in several sizes, noted by the number of ports available -- a four-port hub can connect four computers, an 8-port hub can connect up to eight computers and so on. Most hubs are stackable. A stackable hub has a special port that can connect it to another hub to increase the capacity of your network. So if you start with a four-port hub but eventually have five computers, you can buy another four-port hub and connect it to the one you already have, increasing the potential number of computers on your network.

To connect the computers, you will need Unshielded Twisted Pair (UTP) Category 5 cable. This type of cabling is designed to handle the 100-Mbps speed needed by Ethernet. You can buy Cat 5 cables in predetermined lengths with the connectors already attached. If you plan to install the Cat 5 cabling in the walls of your house, you can buy the cable in rolls, cut it to length and connect the cable to special wall boxes.

Because an Ethernet network can be configured in many different ways, there are no automated installation programs, and you will have to configure all your network options manually. To read up on how to do this, click here.

Phone Line Networking

Phone-line networking is one of several ways to connect the computers in your home. If your computers are in different rooms, then phone line networking could be a good solution for you. Phone-line networking is easy to install, inexpensive and fast, and it doesn't require any additional wiring. Phone-line networking, most commonly referred to as HomePNA, is based on the specifications developed by the Home Phone Networking Alliance (HPNA). The HPNA is a consortium of key networking technology companies that created a phone-line standard for the networking industry. The current specification operates at 10 Mbps.

To install a phone line network, you will need to have a phone jack near every computer that you wish to link to the network. Otherwise, you will have to run an extension cord, or install new wiring. Although a phone line network runs at a reasonable speed, it is still ten times slower than Ethernet (100 Mbps) and if you are going to be sending out large amounts of data, you may want to consider using a faster method of networking.

In HomePNA, voice and data travels along the same wires without interfering with each other. This is accomplished by broadcasting the data at a different frequency from the voice transmissions. The process is similar to how radio stations are broadcast over different frequencies.

If you decide that HomePNA is best for you, here are the basic steps:

Buy a kit, making sure you have a HomePNA card or external adapter for each computer in your home.
Install the hardware (internal card or external adapter).
Plug the included cable into the hardware and into the phone jack.
Install the software

HomePNA adapters come in two versions: internal card (PCI) or USB. You can buy kits consisting of HomePNA cards for two computers, an installation CD and all the necessary cables for about $90 to $110. If you plan to use a laptop computer that does not have a USB port, you can either buy a USB-to-PCMCIA adapter ($50) or get a parallel-port USB adapter.

Power Line Networking

Power line networking uses electrical wiring in your house to create a network. Like phone line networking, power line networking is built around the idea of adding no new wires to your home. Even more convenient is the fact that you will not need a phone jack next to every computer. Instead, you connect each computer together using electrical outlets. Power line networking in the least expensive method of networking, but the connection can be rather slow - between 50 kilobits per second (Kbps) and 350 Kbps.

**Figure 2: Passport Wall Plug**

There are currently two competing power-line technologies. The original technology is called Passport, by a company named Intelogis. A new technology called PowerPacket, developed by Intellon, is the now the standard for power line networking, according to HomePNA. Intelogis provides a kit that connects two computers and one printer for $59. Additional adapters cost about $40. There are specific versions for computers or printers, so make sure you get the correct one. Since the network does not affect power usage or consumption, no additional monthly costs are incurred. The cost of PowerPacket technology is expected to be comparable to HomePNA solutions and significantly less than 802.11 wireless solutions.

To install a power line network, you will need to use your computer's parallel port or USB port. A wall device (part of the Passport or PowerPacket kit) will be directly plugged into an electrical outlet. To use Passport technology, a parallel cable is plugged into the wall device and into the parallel port of the computer. The power-line network must be the last item connected to the parallel port. Initial PowerPacket devices connect via a USB or Ethernet cord from the computer to a small wall adapter. Subsequent devices will have the circuitry built in, meaning the only connection needed would be the power cord. Once the hardware is in place, install the networking software (from your kit) on your computers.

Wireless Networking

WiFi is the wireless way to handle networking. It is also known as 802.11 networking and wireless networking. The big advantage of WiFi is its simplicity. You can connect computers anywhere in your home or office without the need for wires. The computers connect to the network using radio signals, and computers can be up to 100 feet or so apart. Many laptops now come with a WiFi card, making it even easier to use WiFi technology.

To install a wireless network, you will need to do the following steps:

Buy a 802.11a, 802.11b or 802.11g network card. 802.11g has the advantage of higher speeds and good interoperability on 802.11b equipment. For a laptop, this card will normally be a PCMCIA card that you slide into a PCMCIA slot on your laptop. Or you can buy a small external adapter and plug it into a USB port. For a desktop machine, you can buy a PCI card that you install inside the machine, or a small external adapter that you connect to the computer with a USB cable.
Install the card
Install the drivers for the card
Find an 802.11 hotspot
Access the hotspot.

A hotspot is a connection point for a WiFi network. It is a small box that is hardwired into the Internet. The box contains an 802.11 radio that can simultaneously talk to up to 100 or so 802.11 cards. There are many WiFi hotspots now available in public places like restaurants, hotels, libraries and airports, and you can also create your own hotspot in your home. For information on creating hotspots, click here.

On the newest machines, an 802.11 card will automatically connect with an 802.11 hotspot and a network connection will be established. As soon as you turn on your machine, it will connect and you will be able to browse the Web, send email, etc. using WiFi. Older machines require a little more work. First, you must access the software for the 802.11 card -- normally there is an icon for the card down in the system tray at the bottom right of the screen. Then, click the "Search button" in the software. The card will search for all of the available hotspots in the area and show you a list. Double-click on one of the hotspots to connect to it.

File Sharing

One of the most common activities on a home computer network is file sharing. Sharing files is relatively easy, and once it is set up, you can share files with any computer on your network. In most Windows systems, to use file sharing you have to first make sure that file sharing is enabled. To do this, right click the Network Neighborhood icon on your desktop. Select Properties from the menu, and look for Client for Microsoft Networks.

**Figure 3: File Sharing**

When a computer is a "client" of a network, that computer can communicate and share information with other computers that are clients of the network. Sometimes the software required to make a computer a client of a particular type of network isn't loaded. If that's the case:

Click Add in the Network Properties window.
Choose Client from the list of choices in the window that pops up.
Click Add. You will see a list of different companies or vendors on the left pane (side) of the window.
Click Microsoft in that left pane. This will bring up a list of Microsoft's software clients in the right pane.
Choose Client for Microsoft Networks from the list and click OK. Windows will copy all of the necessary files and may prompt you for the Windows System CD. If so, insert the CD and continue.

Once the software is installed, you should be back to the original Network window. To enable file sharing, click the button labeled File and Print Sharing. You will see two options, one for sharing files and the other for sharing printers. Click the box next to each option to enable it. Once it is enabled, you will see a checkmark in the box. You may then close the sharing-options window. Click the Access Control tab near the top of the Network window. For easier control of who can access which files, click the box beside Share-level Access Control. Then, close the Network window. File and Print Sharing. files printers Access Control Share-level Access Control

You must now select which folders you want to share. Sharing your entire hard drive is not recommended. It is too easy for someone to accidentally delete an important system file if the whole disk is shared. Instead, create folders that will be used specifically to share files. Once you have identified the folder(s), right click on the folder to view the pop-up menu. Select the Sharing menu item. A window will open with several options. The default choice for sharing is Not Shared. Change this to Shared As and type in a name for the shared folder. The "Shared As" name does not have to be the same as the name of the folder, but it makes it easier to remember if it is.

Printer Sharing

**Figure 4: Printer sharing**

Once you have completed the steps to enable file sharing, you're ready to create a shared printer for your network. On most Windows systems, this can be done by locating the Printers menu. To find Printers, click on the Start button and choose Settings. From the menu that appears, choose Printers. A window will appear showing all the printers on the local system. Right click the icon of the printer you wish to share. Select Sharing from the pop-up menu. The Properties menu for that printer will pop-up. Select the Sharing tab if it is not already selected. Click the Shared As option, and type in a name for your printer. You may also wish to set up a password for accessing the printer, and can do so here. Click OK to save your settings. Your printer is now shared.

You may now access the printer from another computer: To do this, go to that computer and open the Printers window. Double-click the Add a Printer wizard. Choose the Network Printer option and click Next. The wizard will display a list of all shared printers on the local area network (LAN). Click on the printer you wish to access and click Next again. The wizard will then install the appropriate driver if it is available, or else request that you put in a disk or CD with the driver software. Once the wizard finishes installing the software, the printer will appear to your system just like a local printer.