Many schools, districts, institutions, libraries, and education agencies have established in-house connections between computers. Some have provided mechanisms by which persons working in an organization can connect with computers outside of the organization. Often individuals establish their own linkages to networks such as the Internet by purchasing software and using a commercial service (i.e., a company that will connect you to a network so that your computer can exchange information with other computers). More frequently, in the education environment, a school will connect through a district, county or state service. A college or university department might connect through a central entity within the organization as well.

Understanding How Networking Works
A network is the complete set of hardware, software, and wiring (or, in the case of 'wireless networks', no wiring) used to connect computers together to share information and peripherals, such as printers, scanners, and modems. Networks allow information to be exchanged directly between numerous computers without having to be transcribed by hand.

The smallest networks are Local Area Networks (LANs) in which 2 to 500 or more computers are connected within a small geographic area, often a single building or classroom. Larger networks called Wide Area Networks (WANs) connect the LANs together. They may use telephone lines, dedicated cables, radio waves or other media to link computers that can be thousands of miles apart.

See Figure 3.1 to view a sample district network design.

The geometric configuration of the computers is called the topology of the network. The standards and rules by which the computers communicate on a network are called protocols. Information is stored in networks in two basic configurations:

• In peer-to-peer networks, users store their files on their own computers so that anyone else on the network can access the files (and the user, in turn, can access files stored on the other networked computers as well).
• In client/server networks, users store their files on a central computer from which files are accessed directly. In the client/server network, the server is the central computer that stores the information, and the client is the computer (and user) that accesses the information from that central computer. Many people think that it is generally easier to manage, back up, and protect data in a client/server network.

A Note About the Internet
Perhaps the ultimate WAN is the Internet, which is a matrix of networks. The Internet connects quite literally millions of supercomputers, mainframes, workstations, personal computers, laptops and more.

The most popular application available via the Internet is the World Wide Web (WWW). It is the primary navigation tool for using the Internet. More often than not, when people say they are "online" they mean that they are connected to the Internet. Education organizations can connect to the Internet via one computer or many. A single computer might use a regular telephone line to connect to the Internet through an Internet Service Provider (ISP) (such as America On Line, Earthlink, etc.). A school or office might connect numerous computers together into a LAN, as described above, and then connect those computers to a hub/switch and on to the router, which in turn is connected to the wire (or cable, or satellite) that is connected to the ISP.

It is not very efficient for an organization to have numerous computers using modems to connect to the Internet over telephone lines. Rather, it is preferable to connect to the Internet over a "digital" line that is dedicated to organizational use. A digital line allows more than one computer to access the Internet at any time. The number of computers that can access the Internet at one time is limited only by the size of the wire connecting the site to the ISP. In terms of installing digital lines in a K-12 education environment, the Federal government currently provides funds through the E-rate discount program (discussed later) which is intended to defray up to 90% of associated costs.

Developing an Inventory of Networking Capabilities
The inventory of the LAN or WAN should be maintained by the office responsible for the network. If the school is responsible for making sure that the network is operational, then the school should maintain the inventory. However, if the district, county or state maintains the network, then the inventory should be retained at that level. An accurate inventory is required if the network is to be maintained adequately. You should develop an inventory of the equipment and software specifically allocated to the network and note where they are located (see Table 3.3 as an example).