Now that we've looked at some of the theory of computer networking, let's look at home networking from a practical perspective. The reasons for creating a home network can vary greatly. The following are some examples of what you can do with a home network:
Share a single Internet connection among many computers
Play computer games with friends and family members
Enjoy your favorite audio and/or video content from any room in the house
Print documents from any computer
Collaborate with friends on homework
Create your own personal website
Share photographs with family members and friends
In the early days of the Internet, when the only use for it was as a university research project, addresses were easy to get. There were only four universities on what would eventually become the worldwide Internet as we now know it. As the concept caught on, however, more and more schools, government institutions, and commercial enterprises saw the potential of the Internet and adopted its use in great numbers.
You have seen examples of IP address in this book; they generally take the form w.x.y.z, which is often referred to as dotted-decimal notation. This is basically the human-readable format for a binary number 32 bits in length. Recall that a binary number has only two states: It is either a 0 or a 1, which means it is either on or off.
There are 232 (4,294,967,296) IP addresses available. While this seems like an inexhaustible supply, there are a few factors to be aware of. IP addresses in the current implementation (IP version 4) are broken up by classes:
Class A addressesIn a Class A address, the first 8 bits (equivalent to the w in the w.x.y.z notation) refer to the network number.
Class B addressesClass B networks are identified by the fact that the first 16 bits (equivalent to the w.x in the w.x.y.z notation) refer to the network number.
Class C addressesClass C networks are identified by the fact that the first 24 bits (equivalent to the w.x.y in the w.x.y.z notation) refer to the network number.
Class D and E addressesClass D and E networks exist but are not used for general communication purposes.
The Internet has grown and continues to grow at a tremendous rate, and we will in the not-too-distant future use up the supply of IP version 4 addresses.
To solve this impending problem, IP version 6 is in development. In IP version 6 there will be 128 bits used for an address, which means there can be 3.4x1038 unique addresses. This means that there are enough addresses in IP version 6 to accommodate each grain of sand on 300 million planets the size of Earth, assuming that the Earth were made entirely out of 1 cubic millimeter grains of sand. Suffice it to say, that is a lot of addresses, and we shouldn't run out any time soon. Personally, I'm looking forward to the possibility of having my own IP address brain implant and the ability to address all my devices with that implant.
If this sort of information really floats your boat (as it does mine), you owe it to yourself to get a copy of the late W. Richard Stevens's TCP/IP Illustrated, Volume 1, which covers every aspect of TCP/IP in minute detail. You can also do a search online to get more information about IP version 6.
If you run a business out of your home, the advantages of a home network should be obvious: Everything that makes a business runincluding communications, advertising, and financial transactionsis carried out on the Internet daily. Home networks are also handy for non-business use. If you have a single computer connected to the Internet, scheduling conflicts are bound to arise. Mom may be surfing the Internet, with Dad waiting his turn and the kids wanting to see the latest music video or play the latest game online at the same time. Even with multiple computers in the household, this situation can easily arise if there is but a single conduit to the Internet. Further, without a network, printer access is limited to the person whose computer the printer is connected to. All these potential aggravations can be solved by installing your own home network.
As an example of one of the idiosyncrasies that technology brings to the table, my wife and I were both in the same house recently, using two different computers. Rather than calling out to me as we might have done in the past, my wife used instant messaging to send a text message to my screen. While this may seem trivial, the power that such a technology offers should not be overlooked. Without having to interrupt in any appreciable way what either of us were doing at the time, we were able to communicate very effectively.
Setting up a home network requires a bit of thought. You need to think about what your needs are, and then you need to decide what devices you need to purchase in order to connect your computers. The following are some of the items you might need:
A wireless access point (WAP)
A wireless network card(s)
An Ethernet hub or switch
A DSL or cable modem
A NIC for wired solutions
Category 5 Ethernet wires
This list is a starting point for the items to consider for your network. As your network matures and possibly becomes more sophisticated, you can add to this list as you see fit.