Home Networking Do-It-Yourself For Dummies

Part I

Doing Your Homework

In this part . . .

Don’t worry — it isn’t a graded assignment! But you do need to know why you’re building a home network and understand some basics about networking before you get started. So in this part, I help you explore the possibilities for your home network, explain some networking terms and concepts, and describe some basic networking equipment.

Chapter 1

Why Do You Need A Home Network?

In This Chapter

arrow Learning about LANs and WANs

arrow Recognizing the benefits of home networks

arrow Deciding whether to build a wired or wireless network

Computer networks allow you to easily share resources with others. These resources may include Internet access, shared files and folders, printers, and much more. In this chapter, you explore the benefits of creating your own home network.

A Network by Any Other Name

A network is a group of computers that communicate with each other in order to share resources, such as Internet access, computing power, files and folders, printers, and even the computers themselves.

If you’ve worked on a corporate or office network, you may have heard the network referred to as the LAN, which is simply a local area network. Your home network can also be correctly described as a LAN. There is no hard and fast rule for how small or large a network must be in order to be considered a LAN. It may consist of as few as two computers or as many as several hundred computers.

Another acronym you may hear when referring to a network is WAN, or wide area network, which connects multiple networks together. For example, a corporation may connect several of its locations together on a private WAN. The biggest example of a WAN is the Internet, which connects networks as small as one computer to as large as thousands of computers together over the Internet.

Fill-in-the-blank area networks (_AN)

Although networks are most commonly referred to as LANs or WANs, you may occasionally hear other variations and acronyms thrown around, such as:

check.png Personal area network (PAN): Connects your personal electronic devices together, or to a larger network such as the Internet. Examples of devices that might be connected via a PAN include laptop computers, cellular phones, PDAs (personal digital assistants), and other mobile devices (such as Blackberry smartphones and iPods). These devices can be connected via wired technologies such as USB and FireWire, or wireless technologies such as Wi-Fi, Bluetooth, and infrared (IR or IrDA). A wireless PAN is also sometimes referred to as a WPAN.

check.png Storage area network (SAN): Connects servers to a separate physical storage device (an array of disks). SANs usually comprise several terabytes or more of disk storage and are typically found in larger corporate networks.

check.png Virtual local area network (VLAN): VLANs are created on network switches as a way of logically grouping users and resources together (such as different departments), providing more efficient use of network bandwidth and additional security. Although it is possible to create VLANs on your home network, it adds much complexity and is rarely necessary.

check.png Wireless local area network (WLAN): Also known as a Wi-Fi network. A wireless network uses access points and wireless adapters to connect devices together. You find out about wireless networks in Chapter 4.

check.png Campus area network (CAN): Connects your bathroom to the rest of your network. Just kidding! A CAN connects multiple buildings across a high-speed network backbone.

check.png Metropolitan area network (MAN): I’ll steer clear of any jokes here! A MAN extends across a large area, such as a town or city.

A Home Network for Everyone

Fifty years ago, most homes had only one television and one telephone at best. Just 20 years ago, most homes had only one computer, if any at all. Now, as computer prices have plummeted, homes commonly have a computer for practically every member of the family. The benefits of a home network include the following:

check.png Sharing high-speed Internet: In the not-too-distant past, sharing an Internet connection across multiple computers would have been laughable. Dialup modems, accompanied by their trademark symphony of screeches, beeps, and other harmonious sounds, are as aggravating as they are slow. With a top speed of about 56 Kbps over a traditional home telephone line, surfing the Internet is an exercise in patience. But as high-speed Internet with cable and DSL routers and modems has become more accessible (and affordable), sharing an Internet connection has become commonplace. (See Chapter 8 for more on connecting your home network to the Internet.)

check.png Sharing files and printers: Moving files over a home network is as easy as cutting and pasting, dragging and dropping, or pointing and clicking. A home network also makes it possible for you to share printers. No more tying up the printer computer to print a massive homework assignment or work project. (In Chapter 7, I tell you how to set up printer sharing.)

check.png Playing games, videos, and more: A home network allows multiplayer games, so you can enhance your game-playing experience well beyond Solitaire! You can also connect your digital video recorders (DVRs) and game consoles to your network to entertain the entire family (see Chapter 10).

A Home Network for One

A network is traditionally defined as two or more computers connected together. But even if you have only one computer, or you live alone, you may still find a home network beneficial. Wireless networks are ideal in both of these situations, particularly if you have a laptop computer. A wireless network with a laptop computer gives you the freedom to work from your desk, your bedroom, your kitchen, your backyard — just about anywhere in and around your home! And don’t forget about the other wireless devices you may have, such as a game console and your mobile phone.

Building a SOHO: When Home and Office Become One

As home businesses and telecommuting, or working from home, have become more commonplace in today’s business world, a small office or home office (SOHO) network is now a necessity for much of today’s workforce. Much of the equipment for a SOHO network is the same as for a home network, but there are a few differences. For example, you may also need to connect a Voice-over-IP (VoIP) phone to your home network or set up a virtual private network (VPN), which I cover in Chapter 9. Depending on what type of work you’re doing in your home office, you may also have regulatory compliance requirements (which I discuss in Chapter 15).

To Wire or Not To Wire

Your two choices for connecting computers in a network are wired and wireless. Wired networks are generally faster and more secure than wireless networks, but wireless networks provide mobility and convenience if you have laptop computers and mobile devices. If your home isn’t prewired with Ethernet network cables (see Chapter 3), running network cables throughout your home can be a time-consuming chore and unsightly (imagine blue cables running along the walls and under rugs), unless you actually go through the trouble of running your cables behind walls and furniture.

remember.eps Although a wired network generally provides faster network speeds than a wireless connection, that doesn’t mean you’ll get faster Internet speeds with a wired network. Wired networks typically operate at speeds of 100 or 1000 Mbps (megabits per second) and wireless networks operate in the 54 Mbps range. But a residential high-speed Internet connection typically provides only 5 Mbps of Internet bandwidth. So your bottleneck will almost always be your Internet connection, whether you have a wired or wireless network.

Of course, you don’t have to be a purist when it comes to home networking. It’s entirely possible to have a little bit of both, and this approach may be advantageous. For example, depending on the construction materials used in your home, you may find certain areas, such as your basement, difficult to cover with a wireless network. Running a network cable from your wireless router down to your basement, and connecting it to a hub or switch in the basement is one way to address spotty wireless coverage.

Both wired and wireless networks are fairly inexpensive to set up and require just a few basic pieces of networking equipment, which I explain in Chapters 3 (wired) and 4 (wireless).

Chapter 2

Understanding Networking Basics

Tasks Performed in This Chapter

arrow Getting familiar with basic Network properties

arrow Learning about IP addresses

arrow Addressing your network devices with DHCP

arrow Addressing your network devices manually

IP addresses, subnet masks, and default gateways form the logical building blocks of network devices. You have more than likely seen these settings on your computer before, but you may not have known what it all meant. More than likely, any time there was an issue with one of these settings, you got an error message telling you to contact your system administrator. Well, on your home network, that’s you!

In this chapter, you learn enough about IP addresses, subnet masks, default gateways, and how to configure these network properties to make you dangerous — and get you up and running on your home network.

Understanding Basic Network Properties

To configure the various devices (such as computers, printers, routers, switches, and gaming consoles) on your home network, you need to know some basic information, including:

check.png IP address

check.png Subnet mask

check.png Default gateway address

check.png DNS server addresses

In the following sections, I explain what each of these network properties are, what they do, and how you obtain them. Then, I show you how to configure your network devices with all of these properties, both the hard way (manually) and the easy way (automatically)!

remember.eps I’m not just showing you how to configure your network the hard way so that you can impress your geekiest friends! Unfortunately, not all network devices can be automatically configured, so you may need to know how to configure these properties manually.

IP addresses

Every device on a network must be uniquely identified with an IP (Internet Protocol) address. An IP address consists of four sets of numbers from 0 to 255, separated by a decimal, such as

192.168.1.200

technicalstuff.eps Although the numbers in an IP address may appear random, there is a method to the madness. Each of the four numbers that comprise an IP address is known as an octet because it consists of 8 bits. With 8 bits, there are 256 possible combinations from 0 to 255.

IP addresses are assigned to organizations by the Internet Assigned Numbers Authority (IANA). That’s right, organizations. So how do you, an individual, get your very own IP address? Your Internet service provider (ISP) can lease a permanent IP address to you, but that isn’t really necessary, unless you’re running your own Web or e-mail server on your home network. More often, your ISP dynamically assigns an IP address to you from a pool of addresses that IANA has assigned to your ISP. If your high-speed Internet connection is more or less always connected, you essentially get a permanent IP address anyway. Of course, there’s no guarantee that you’ll always get that same IP address (for example, if your router is reset or your ISP has a timeout set on your connection you may get a different IP address assigned), so if you’re running your own Web or e-mail server, you’ll need to get a permanent IP address from your ISP and manually configure it on your server. Otherwise, a dynamically assigned IP address is fine.

However, your ISP will give you only one IP address, and that one is assigned to your modem or router. You still need to assign a unique IP address to each of your network devices. Fortunately, IANA reserves three ranges of IP addresses for private use:

10.0.0.1 to 10.255.255.254

172.16.0.1 to 172.31.255.254

192.168.0.1 to 192.168.255.254

These IP addresses are never routed over the Internet, so you can use them on your home network as you see fit. But IP addressing can get very complicated very fast, so it’s best to keep your IP numbering scheme as simple as possible. The easiest way to do this is to make the first three groups (or octets) of numbers in your IP address the same, and focus only on the last group. In the last group, start numbering the routers, computers, and other devices on your network from 1 to 254. For example, if you have the following devices on your network, you might assign them IP addresses as follows. (See Figure 2-1.)

Figure 2-1: A simple IP addressing scheme.

Because private IP addresses cannot be routed over the Internet, your router or firewall must translate your private IP addresses to a public IP address (or IP addresses), which can be sent over the Internet. This is known as Network Address Translation (NAT) or Port Address Translation (PAT). NAT translates a private IP address (such as 192.168.1.2) to a public IP address (such as 71.156.85.214). PAT translates a range of private IP addresses (such as 192.168.1.2 to 192.168.1.254) to a single public IP address. Most home routers and firewalls sold today are preconfigured to perform NAT, or you can easily enable it, usually through a check box option or setup wizard depending on your router or firewall model.

tip.eps Although NAT and PAT are distinctly different, the overall function (that is, translating IP addresses) is the same. Many router and firewall vendors do not distinguish between NAT and PAT in the user interface and simply refer to the address translation function as NAT.

Subnet masks

The second important piece of an IP address is the subnet mask. Similar to an IP address, the subnet mask consists of four numbers from 0 to 255 (but in the case of a subnet mask, only certain numbers within that range can be used), separated by decimal points. A subnet mask separates an IP address into two logical portions: a network portion and a host portion. The network portion identifies a unique network, and the host portion identifies an individual device on that network (such as a computer or printer). This is somewhat analogous to a 10-digit phone number, in which the first three digits represent the area code (or network), and the 7-digit phone number represents a unique phone line in that area (or host). But rather than limiting the Internet to 999 unique networks (a 3-digit area code only gives us 999 unique areas), a subnet mask allows you to have infinitely more unique networks by allowing the area code to be a variable number of digits within the IP address (for example, 3, 6, or 9, of the 12 total digits in an IP address). The subnet mask tells a computer or router how many of the digits in the IP address represent the network and how many of the digits represent unique devices (or hosts) on the network.

technicalstuff.eps A subnet mask can actually consist of far more combinations than just 3, 6, or 9 digits as described previously, but this oversimplification is sufficient for understanding the purpose of subnet masks.

Like IP addresses, subnet masks can get very complicated, very fast. The number 255 in a subnet mask essentially identifies the network portion of an IP address, while the number 0 essentially identifies the host portion of an IP address. For home networking purposes, it’s usually sufficient to simply use a subnet mask of 255.255.255.0. Referring to the example in Figure 2-1, a subnet mask of 255.255.255.0 tells every device on your network that it belongs to the 192.168.1.0 network (the last 0 is just the default designation for a network; it is never actually assigned to a network device), and that the last number (1 through 5 in the previous example) is the unique host address.

warning_bomb.eps This is a very simple description of IP addressing and subnet masks. Getting any fancier than this with your IP addressing scheme requires advanced networking knowledge and is rarely necessary on a home network.

Default gateway address

The default gateway, in most cases, is simply the IP address of your Internet router. Your router will typically have two IP addresses associated with it. One is the private IP address that you configure on your router (such as 192.168.1.1), and the other is the public IP address that your ISP assigns to your router — which can be a dynamic (temporary) or static (permanent) IP address. Although you can configure all of your network devices to use either the router’s public or private IP address as the default gateway, it is usually best to use the private IP address (because the public IP address might change if it is not a permanently assigned static IP address from your ISP).

Continuing with the example in Figure 2-1, the default gateway address tells the various network devices how to get to an IP address that isn’t on your local network. For example, if you’re using your laptop and want to go to www.microsoft.com (IP address: 207.46.232.182), your laptop needs your router’s help to get there. Rather than keeping track of every possible address on the Internet, your laptop simply hands the task to your router, whose job it is to find the best route to www.microsoft.com (among others). But how does your router know the IP address for www.microsoft.com (or any other Web site address for that matter)? That’s the job of DNS, which I explain in the next section.

Domain Name System (DNS) server addresses

The Domain Name System (DNS) is the phonebook of the Internet. Although it’s possible to surf the Internet without DNS by simply entering the IP address of the Web site you want to visit into your browser’s address bar, it’s not very practical. Just try memorizing the IP addresses of a few of your favorite Web sites,