How+Computers+Communicate

Computer Communication

 How Do Computers Communicate with One Another?

 In order for computers to share information directly, they must be linked to one another through a network. When two or more computers are connected by cables or radio signals, they form a network. When a computer is not connected to a network, it is called a stand-alone. There are two advantages to networking computers: access to information, and access to equipment.

 ACCESS TO INFORMATION

 By networking computers, information can be transmitted directly from one computer to another. Networking allows many people to share files and software in several ways:

 · All users on a network can access software from a central location.

 · All users on a network can access shared files.

 · A user can connect to a network from another location, and then access all of his or her files and shared software.

 ACCESS TO EQUIPMENT

 Computers on a network can share hardware. For example, one or more printers can be added to a network. All computers on that network can share those printers. Networks also allow computers to share other hardware, such as modems and projection devices.

 TYPES OF NETWORKS

 There are two main types of networks.

 A LAN (local area network) consists of a group of networked computers that are all located in one building. This could be a school, a classroom, or even your home. A LAN can be as simple as two computers networked in order to share a printer. It can be as complex as an entire office building with hundreds of computers networked together so that users can share software, hardware, peripherals, and information. When a LAN is constructed using wireless technology, it is called a WLAN, or wireless local area network.

 A WAN (wide area network) is a group of networked computers located in a variety of locations in a large geographic area. For example, some school boards have all the computers from each school in an entire city networked together through a WAN. WANs can he set up to transmit information between computers using a variety of media including telephone line, cable, and satellite.’

 Whether you are setting up a LAN or a WAN, there are different ways of setting up communication. Networks are typically arranged in one of two ways.

 · In a client/server network, one (or more) computer becomes the leader of the other computers in the network. The leader is called the server. The server is generally bigger, faster, and more powerful than the other computers. In addition, it can run the network operating-system software. The other computers in the network are called the clients, or nodes. They connect to the server through a switch or hub. Like the hub of a wheel, the switch or hub is a central device that connects several computers together or several networks together. It allows the computers to share the server's processing power and store information. Each client must have a NIC (network interface card) to be a part of the network. The NIC is an expansion card that allows the computer to act as a client or node in the network. Usually, any network that has more than a dozen computers uses this type of arrangement. .

<span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> · The peer-to-peer network arrangement allows computers to share resources and files, as well as access resources and files. This means that individual nodes act simultaneously as clients and servers. Much like the client/server arrangement, the peer-to-peer arrangement requires a hub or switch, as well as a NIC for each node. The major advantage of peer-to-peer networks is that they are inexpensive to set up; however, they tend to burden nodes because they have to play the server’s role.

<span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> Server <span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> The server is a powerful computer that handles all the network’s shared resources. [Image has been omitted]

<span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> Switch <span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> The switch, formerly known as the hub, is the central device where all the nodes and peripherals connect so that they can communicate with one another. [Image has been omitted]

<span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> Cables <span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> Special cables are used to connect all the parts of the network. [Image has been omitted]

<span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> Computers <span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> Each client computer (also called a node) is connected by a cable. Each computer also contains a network Interface Card (NIC), which is also an expansion card.

<span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> HOW NETWORKS ARE ARRANGED

<span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> All networks consist of two or more pieces hardware connected together by cables or wireless technology. The network topology is the physical layout of the cables that connect the nodes and peripherals of the network. There are two basic network topologies: bus topology and star topology.

<span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> 1. In bus topology, all nodes and peripherals are attached to one main cable. One broken connection will bring down part or all of the network.

<span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> 2. In star topology, all nodes and peripherals are connected to one hub, or switch, at the centre of the network with separate cables. <span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> One broken connection will not affect the rest of the network.

<span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> WARCHALKING

<span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> Wireless networks are increasing in popularity, especially in family homes. In fact, many new computers come already equipped with built-in wireless transmitters. However, if you do not use caution, you may not be the only one connecting to your network. Some people practice warchalking, which involves connecting to unprotected Wi-Fi networks, and then telling others about it.

<span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;">Questions

<span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> 1. What are the advantages of networking computers together?

<span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> 2. Identify one disadvantage of networking computers together.

<span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> 3. What technology allows computer networks without wires?

<span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> 4. Describe the difference between a LAN and a WAN.

<span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;"> 5. Name and describe two ways that computers communicate with one another. <span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;">6. Name the two main network topologies. <span style="font-family: 'Arial Black',Gadget,sans-serif; font-size: 150%;">7. Which network topology would you choose if you were responsible for creating your own network? Why?