Home Networking

How and why a home network



With a home network you can do things like:

And those computers don't have to be the same. They can all be running different versions of Windows, or be running different operating systems entirely. It can be a combination of Windows, Linux, Macintosh and Unix systems. The network allows them to communicate with one another because they all speak the same network language.

As Sun Microsystems said in their advertisements: "the network IS the solution".

There is a lot of information in this section. If you are unsure of yourself, hire an expert or ask someone who understands networks to set up yours.

If you're ready to tackle this yourself, strap on your seat belt and here we go.

Network Basics

The key to networking is a router. The router links multiple computers to each other and to the Internet (the network of networks). The router speaks TCP/IP (Transmission Control Protocol/Internet Protocol) and hands out IP addresses to all the attached computers in your house. These addresses look like 192.168.1.101. Four numbers between 0 and 255 separated by a dot (.). These are the IP addresses and the process is called DHCP or Dynamic Host Configuration Protocol.

For home networking there are two types of IP addresses. Those on your personal network and those on the Internet. You can have up to 256 computers on your network. These have an IP addresses of 192.168.1.1 through 192.168.1.255. In fact, your router probably has an address of 192.168.1.1. Most do.

To check, type 192.168.1.1 in the address box of your web browser and you will get a router login screen:

Your router manual will tell you the default User Namee and Password for your router. It varies by brand.

If 192.168.1.1 does not take you to your router try 192.168.2.1. If that doesn't work you will have to find the router manual.

If you've lost the manual you can find a .pdf copy on the Internet. Go to Google and search on +router +model number.

The other type if IP address is your Internet address. You can find your Internet IP address by going to What's My IP. This is the Internet IP address of your router. If you don't have a router it's the IP address of your computer, and you are exposed to Internet hackers. (see Security Help for more information on why you need a router for any broadband connection.

Network Devices

LinkSys Components

To the right is a picture of the typical home networking components.

The top (black) device is a VoIP (Voice over IP) adapter. This allows telephone calls over the Internet instead of through a telephone company. This particular one is from Vonage and has an IP address of 192.168.15.1.

The second device is a WAP or Wireless Access Point. This device transmits and receives wireless signals throughout the house so laptop computers and PDA's can share printers, files and access the Internet.

The Third device is a Switch or Hub. This particular one allows the wired attachment of up to 16 additional computers to the network. Each on light represents an attached computer. These come in various sizes ranging from 4-255 computers.

The fourth device is the router itself. This particular one allows the direct attachment of 4 computers. It hands out IP addresses to all the other devices. This particular router is a LinkSys BEFSR41.

The fifth device is a cable modem. This device attaches to Comcast and passes the Internet signal to all the other devices. You will have a DSL modem if your broadband is from BellSouth (now AT&T).

 

Now you don't need all these components. Many of the newer network devices combine function in a single device. For example, the current VoIP adapter from Vonage contains both a router and a WAP. The current cable modem from Comcast contains a 4 port router and a WAP. Most DSL modems from AT&T contain a router, a 1-4 port hub, and a WAP. This raises the problem of multiple routers on the same network. You cannot have multiple routers passing out IP addresses. This WILL cause problems. Fortunately every router has a setting to disable DHCP. Remember only one router per network.

IP Addresses

An IP address consists of four Hexadecimal numbers. This means there are only 2564 or 4,294,967,296 possible IP addresses. This raises a problem because it is estimated there are already over 2 billion Internet users worldwide. The Internet was designed in a time when IBM thought the worldwide market for computers was a couple hundred. It was felt that 4 billion was more than enough IP's. So much for the experts.

The original intent was for every Internet user to have his or her own IP address. We ran out of IP addresses back in 1995 and Internet growth started its explosive climb. A standard called IPv6 was adopted in 1994, but every router on the Internet has to be upgraded to implement it so progress has been slow and other less expensive schemes like IP sharing have been adopted by ISP's instead of IPv6. For those interested a complete description of IPv6 may be found here.

MAC Address

In addition to the IP address, there is a MAC or Media Access Control address on every network device. The MAC address is 8 hexadecimal digits. Every network component has a MAC address. Since an Hexadecimal digit can represent 0-255, there are 2568 or 4,722,366,482,869,645,213,696 possible devices. There is room for a lot of network devices. A bit better planned than IP addresses.

Routers

This is how a router works.

Every computer attached to the hub or switch portion of a router is assigned an IP address through DHCP. Since every computer, network card, or network device has a unique MAC address the router associates a MAC address with an IP address. If you log into your router and display the DHCP table you will see that association:

in this example, there are currently four computers attached to the router. They have the IP addresses of 192.168.1.102, 192.168.1.103, 192.168.1.104 and 192.168.1.105 with the associated MAC addresses. 192.168.1.101 on this system is taken up by the WAP adapter. An always connected wireless device. In fact, the Palm device (192.168.1.104) is wireless and comes in through the WAP.

Network Hub

Is an early network switch not capable of DHCP used to connect multiple network devices as described here. It is not much used these days and been replaced by the network switch.

Network Switch

a network switch is an intelligent network hub capable of assigning IP addresses or DHCP. All modern hubs are actually switches. They range in size 4 ports to 255 ports.

VoIP adapter

A VoIP adapter allows you to place telephone calls over the Internet. Most telephone systems already use the Internet for long distance calls. The VoIP adapter is a digital/analog converter allows you to tap into that capability. Comcast offers VoIP telephone service for around $40 per month with unlimited long distance in the U.S.A. Vonage offers a similar service for $25 a month and Skype offers a similar service for about $3 per month, but Skipe uses your computer for a software version of VoIP.

Wireless Access Point

A Wireless Access Point or WAP uses the Wireless Application Protocol and may be a separate device or bundled in with another device. Most often one would buy a combination router/WAP/switch, like the LinkSys Wireless Gateway. Wireless devices come in a number of specifications. The difference is the speed at which they operate. These standards were set by the IEEE or the Institute of Electrical and Electronic Engineers. The standards are the IEEE 802.11 standards, and consist of 802.11b, 802.11g, and 802.11n. 802.11b transmits and receives at 11 mbps. 802.11b at 56 mbps and 802.11n at 160+ mbps.

You configure a WAP with the CD that comes with the WAP. There is no set IP address for a WAP.

When you configure you will be asked to supply an SSID name. The Service Set IDentifier is the name your WAP will broadcast for your network.

You should also encrypt your network using Wired Equivalent Privacy or WEP. Even better is the newer and more secure Wi-fi Protected Access or WPA2 available on some WAP.s.

The reason you want to set encryption is a practice called Wardriving common with teenagers, where they drive up to your house and connect wireless to your network and begin downloading bootleg software or music. When a summons arrives from the RIAA for stealing Copyrighted material, it will have your name on it because all they have is your IP address. The kids will think it's funny, but you will not

Secure your wireless network!!

Sharing devices on the network

Once your network hardware is set-up and secure, you're ready to share resources between the computers on your net. You do this with your Operating System. I'm assuming you are using Windows XP so the examples will be shown using XP.

You can share printers, files, folders, disks, floppy drives, CD drives or thumb drives between computers on your network.

Printer Sharing

To share a printer, go to Start and click on Printers and Faxes:

Start Menu

and a list of the printers and Faxes attached to your computer will be displayed.

Left mouse click on the printer you wish to share, and select

Sharing...

Left click Printers

You will get the following sharing menu.

Click on Share this printer. The default Share Name is usually good unless you have a pet name for this printer.

Click OK and the printer is shared.

Printers

Notice the Driver box. If you have other computers with different versions of Windows, you may need to install additional drivers for the other versions.

 

Using the Shared Printer from other computers

Now go to each computer on your network on which you want to use this printer. We'll stick with Windows XP in this example. Click on Add Printer icon.

Printers

And you will start the Add Printer Wizard and click Next>.

Add Printer Wizard

Which takes you to:

Click A network printer or a printer attached to another computer, as shown, and click Next>.

Add Printer Wizard 2

Click Browse for a printer and click Next>.

Add Printer Wizard 3

You will then get a list of all computers and printers in your Workgroup. Select the printer you wish to add and click Next>.

Add Printer Wizard 4

Click Yes if you want to use this printer as the default printer on this computer. Click Next>.

Add Printer Wizard 5

And you're done. Just click Finish.

Add Printer Wizard 6

Now repeat Using the Shared Printer from other computers for every other computer on which you want to use this printer.

 

Device Sharing

Let's say that you have been using a computer for years, and then you get a new computer. That new computer has a CD Read/Write DVD drive and the old computer only had a CD reader. You can easily share that new CD/DVD R/W drive between all computers on your network.

To share a device first click on My Computer and you will get a list of the hardware devices on your computer. Now, left mouse click on the device you wish to share, like CD Drive (D:), then select Sharing and Security from the menu.

My Computer

You will get Properties Menu for the device you wish to share. Share this folder on the network will be checked. Normal the device letter is fine for a Share Name, so just leave it unless you have a better name. If the device you are sharing in writeable, like a disk drive or a CD/RW drive, decide now if you want other computers on your network to be able to write to it and change the contents. Not a light decision.

For example, you might not want to give network users write access to your C: drive. They may erase important or necessary files that you have. On the other hand, the whole idea behind giving others access to a CD R/W might be for them to backup their data, so write access is necessary. Give checking the last box Allow network users to change my files some thought. If whatever is on it, you do not want to loose, don't check the box.

When you click OK, you're done and the device is shared the way you chose.

Share D:

Sharing Files and Folders