Why use a network? (local area networks) (Compute's Getting Started With: Personal Networking)
by Anne Fischer Lent

Connecting computers in a local area network lets people increase their inefficiency by sharing files, resources, and more. Local area networking has attained much popularity in recent years--so much that it seems networking was just invented. In reality, local area networks (LANs) appeared more than ten years ago, when the arrival of the microcomputer gave multiple users access to the same computer.

These are three of the most common benefits of using a LAN.

* Increased efficiency

* Improved communications

* Lowered costs.

LANs increase the efficiency of workers by letting them exchange data and by eliminating redundant effort. The most common means of sharing information on a LAN is the corporate database. Corporations commonly have several departments performing very differeent tasks, but the departments are generally working with the same type of information. A mail-order company, for example, works with customer name and address data, product numbers and pricing data, and shipping and inventory information. It make the company far more efficient and organized to keep the data in one database, letting each user access the data that he or she needs.

LANs improve communications by offering a way of sending messages electronically. Many networks have full-fledged mail systems, called elctronic mail (E-mail), through which users can send each other everything from corporate memos to informal hellos.

LANs saved money by letting corporations license network versions of software to share among users. Likewise, there can be major savings in hardware purchasing because each network may need only one of each device. Rather than equipping each user with his or her own set of office equipment, a company can create a network consisting of a group of microcomputers with, for example, one laser printer, one tape backup unit, one CD-ROM drive, one fax machine, and one hard drive. By saving money in this way, it's often possible to purchase higher-quality equipment for the group than would have been possible for each individual.

Kinds of Networks

LANs are divided into two types: client-server and peer-to-peer. a client-server network has one or more central computers, called file servers, to which are connected all the other workstations. A workstation is a personal computer connected to a file server. The file server controls all network activity, such as who can use the system and what data users have access to. The advantages of client-server networks include control, security, and speed. Drawbacks can include high cost, difficult installation, and overdependence on a single system (the server). When the server goes down, the whole network goes down.

A peer-to-peer network is a group of microcomputers in which no single system is in charge and all workstations operate as equals. Each workstation can share its files and applications with any other workstations connected to the network. The benefits of peer-to-peer networking include simplicity, lower cost, ease of installation, and ease of maintenance. The drawbacks can include insufficient security, inadequate control, and lack of speed.

With the two basic types of LANs defined, it's important to understand that there are several varieties within each category, just as there's a range of uses for each type. What type of LAN you need depends on your intended use for it.

NetWare: A Client-Server Approach

Novell NetWare is an example of a client-server network. What sets the client-server network apart from the peer-to-peer network is the function of the file server. It, too, is a personal computer, but it runs an operating system such as NetWare to control the network. The file server controls all the workstations on the network in terms of how they access network resources. A network administrator manages the file server by overseeing network security, troubleshooting problems, and more.

The workstations connected to a NetWare network can still function as separate computers with their own operating systems. In fact, even when your computer is connected to a network, what you see on the screen may look the same as when you're not on a network. But when you access the file server, the work you send back and forth is subject to the rights and restrictions imposed by the network administrator. Often, the network administrator takes care of setting users up on the network, which entails physically connecting the workstation to the file server, as well as adding the user name and assigning a password. Users generally know just enough to get their jobs done on the network, but knowing a bit more of the way the network works can sometimes help guide you to some shortcuts and quick fixes that may simplify your networking tasks.

To begin, it's important to understand how a workstation communicates with the file server. First, there's the hardware connection, which consists of a networking card installed in the workstation with a cable that connects to the file server. The second piece of the puzzle is the software. The shell is the software needed for the workstation to communicate with the file server. The network administrator loads the shell onto each workstation. The shell directs your commands either to your own workstation or to the file server, depending on what kind of command it is.

To understand how the file server stores the information you send it, think of a file cabinet as an analogy. The file server is the cabinet. Within it are the drawers, or volumes (Within the drawers (volumes) are folders, or directories. Within those folders (directories) are pieces of paper, or files.