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messages
Another benefit of networking is that networks enable computer users to communicate with one another over the network by sharing messages. Those messages can come in many forms. Email and instant-messaging programs are the most common. But you can also exchange audio or video messages. For example, you can hold online meetings over the network. Network users who have inexpensive video cameras (webcams) attached to their computers can have videoconferences. You can even play a friendly game of Hearts over a network — during your lunch break, of course.
Servers and Clients
The network computer that contains the hard drives, printers, and other resources that are shared with other network computers is a server. This term comes up repeatedly, so you have to remember it. Write it on the back of your left hand.
Any computer that’s not a server is a client. You have to remember this term, too. Write it on the back of your right hand.
Only two kinds of computers are on a network: servers and clients. Look at your left hand and then look at your right hand. Don’t wash your hands until you memorize these terms.
The distinction between servers and clients in a network has parallels in sociology — in effect, a sort of class distinction between the “haves” and “have-nots” of computer resources:
Usually, the most powerful and expensive computers in a network are the servers. There’s a good technical reason: All users on the network share the server’s resources.
The cheaper and less-powerful computers in a network are the clients. Clients are the computers used by individual users for everyday work. Because clients’ resources don’t have to be shared, they don’t have to be as fancy.
Most networks have more clients than servers. For example, a network with ten clients can probably get by with one server.
In many networks, a clean line of demarcation exists between servers and clients. In other words, a computer functions as either a server or a client, not both. For the sake of an efficient network, a server can’t become a client, nor can a client become a server.
Other (usually smaller) networks can be more evenhanded by allowing any computer in the network to be a server and allowing any computer to be both server and client at the same time.
Dedicated Servers and Peers
In some networks, a server computer is a server computer and nothing else. It’s dedicated to the sole task of providing shared resources, such as hard drives and printers, to be accessed by the network client computers. This type of server is a dedicated server because it can perform no other task than network services.
Some smaller networks take an alternative approach by enabling any computer on the network to function as both a client and a server. Thus, any computer can share its printers and hard drives with other computers on the network. And while a computer is working as a server, you can still use that same computer for other functions, such as word processing. This type of network is a peer-to-peer network because all the computers are thought of as peers, or equals.
Here are some points to ponder concerning the differences between dedicated server networks and peer-to-peer networks while you’re walking the dog tomorrow morning:
Peer-to-peer networking features are built into Windows. Thus, if your computer runs Windows, you don’t have to buy any additional software to turn your computer into a server. All you have to do is enable the Windows server features.
The network server features that are built into desktop versions of Windows (such as Windows 10) aren’t particularly efficient because these versions of Windows weren’t designed primarily to be network servers. If you dedicate a computer to the task of being a full-time server, use a special server operating system rather than the standard Windows desktop operating system. A server operating system is specially designed to handle networking functions efficiently.The most commonly used server operating systems are the server versions of Windows.As of this writing, the current server version of Windows is Windows Server 2019. However, many companies still use the previous version (Windows Server 2016), and a few even use its predecessors, Windows Server 2012 and Windows Server 2008.Another popular server operating system is Linux. Linux is popular because it is free. However, it requires more expertise to set up than Windows Server.
Many networks are both peer-to-peer and dedicated-server networks at the same time. These networks haveAt least one server computer that runs a server operating system such as Windows Server 2019Client computers that use the server features of Windows to share their resources with the network
Besides being dedicated, your servers should also be sincere.
What Makes a Network Tick?
To use a network, you don’t really have to know much about how it works. Still, you may feel a little bit better about using the network if you realize that it doesn’t work by voodoo. A network may seem like magic, but it isn’t. The following list describes the inner workings of a typical network:
Network interface: Inside any computer attached to a network is a special electronic circuit called the network interface. The network interface has either an external jack into which you can plug a network cable — or, in the case of a wireless network interface, an antenna.
Network cable: The network cable physically connects the computers. It plugs into the network interface card (NIC) on the back of your computer.The type of network cable most commonly used is twisted-pair cable, so named because it consists of several pairs of wires twisted together in a certain way. Twisted-pair cable superficially resembles telephone cable. However, appearances can be deceiving. Most phone systems are wired using a lower grade of cable that doesn’t work for networks.For the complete lowdown on networking cables, see Chapter 7. Network cable isn’t necessary when wireless networking is used. For more information about wireless networking, see Chapter 8.
Network switch: Networks built with twisted-pair cabling require one or more switches. A switch is a box with a bunch of cable connectors. Each computer on the network is connected by cable to the switch. The switch, in turn, connects all the computers to each other. For more information about network switches, see Chapter 7. In the early days of twisted-pair networking, devices known as hubs were used rather than switches. The term hub is sometimes used to refer to switches, but true hubs went out of style sometime around the turn of the century. In networks with just a few computers, the network switch is often combined with another networking device called a router. A router is used to connect two networks. Typically, a router is used to connect your network to the Internet. By combining a router and a switch in a single box, you can easily connect several computers to the Internet and to each other.
Network software: Of course, the software makes the network work. To make any network work, a whole bunch of software has to be set up just right. For peer-to-peer networking with Windows, you have to play with the Control Panel to get networking to work. And a network operating system such as Windows Server 2019 requires a substantial amount of tweaking to get it to work just right.
It’s Not a Personal Computer Anymore!
If I had to choose one point that I want you to remember from this chapter more than anything else, it’s this: After you hook up your personal