2.3) BEST ANSWER BRAINLIEST your answer will be reported if it is ridiculous

QUESTION:

What is a layer, in the context of this lesson?

a logical unit of a system

a device for remembering something

a computer’s most basic program

the Ethernet word for a packet

LESSON:

Layers

Which of these statements do you think best describes the Internet? It serves as:

a gateway to the whole world's information technology;

a system for getting different machines on a worldwide network to interact;

a means of getting a task done;

a tool for reliably forwarding messages from one computer to another;

a way of organizing information-processing devices so that the one that is needed can be found;

a set of devices that send and receive data frames around the world; or

an arrangement of fiber optic cables, satellite links, and satellite transmissions that join many of the world's computers.

The good news is that whichever answer you selected, you were right. You were wrong only if you said any one answer was right and the others were wrong. The Internet is all of these things.

This list of correct answers does not apply only to the Internet. With a little tweaking, we can make it true for any network. For example, a LAN in a hospital is a gateway to the hospital information technology, and so on, right down to: the LAN is an arrangement of cables connecting many of the hospital's computers.

For technicians, this long list of correct answers poses a problem. When somebody asks for a technician to “fix” a network, just what are they asking for? Which one of these definitions of a network do they mean? It is your job as a network technician to discover where the best answer lies in any particular case. It sounds like a rough demand. Fortunately, the answers can be organized into layers, each of which focuses on a different networking task.

The OSI Reference Model

Imagine a pyramid, one built by the old Mayan civilization of Central America, with several distinct layers or levels. Each layer is supported by the one below it and supports the layer above it. Information technology layers work the same way. Each layer supports the task of the layer above it and depends on the layers below it. You can see how this works by reading that list of Internet descriptions in reverse order.

You will see that the cables support the switches. The switches and other devices are organized according to a system of addresses. The addresses result in the reliable arrival of messages at a receiving machine. The arrival of the message enables Internet users to perform a task. In performing a task, computers interact. All of these things combined give us a gateway to the world's information technology.

Breaking a complex task into layers gives people a logical way of understanding the whole by thinking about its parts. It also provides a way of diagnosing a problem by asking questions and ruling out layers. Your computer cannot connect to the Internet? Well, is the Internet cable plugged in to the machine? No! Then you have found the trouble. If it is plugged in, check the switches and other devices. For example, is the modem working? By climbing up the layers of the pyramid, technicians can efficiently troubleshoot a problem.