Section 1.1 Explain the reasons for using a network Show how networks are useful Describe the difference between synchronous and asynchronous networking

Section 1.1• Explain the reasons for using a network• Show how networks are useful• Describe the difference between synchronous and asynchronous networking• Identify traits that make a good network

Section 1.2• Describe important milestones in networking history• List uses of networks today• Identify emerging network technologies

Section 1.3• Differentiate between careers in the networking industry• Describe duties of each career track in networking

Section 1.4• Identify parts of a computer system• Explain the uses of computer components

pp. 6-101.1 Principles of Networking

Guide to Reading

Main Ideas

Networks help us share data and resources. This increases efficiency and cost-effectiveness. Networks must be reliable, redundant, scalable, secure, and fast.

Key Terms

networkfile sharingresourcessynchronous communicationasynchronous communicationreliableredundantscalablethroughput


Reasons to Use a Network

Computer networks connect systems together to make better use of limited resources.

Networks:

• allow users to engage in file sharing• allow users to share resources• centralize administration and support• improve communication

network A system of two or more computer systems connected together so they can share and exchange data. (p. 6)

file sharing Sharing files between computers; the act of making files on one computer accessible to others on a network. (p. 6)

resource Software or hardware, such as a hard drive, printer, or scanner, that can be shared over a network. (p. 6)



Sharing resources, such as a printer, provides many benefits.



Networking allows two

kinds of communication:

• synchronous (real-time)

• asynchronous

synchronous communication When people talk to each other at the same time. (p. 8)

asynchronous communication A form of data transmission that involves a delay of seconds, minutes, or even days. Communication does not happen instantly. (p. 8)


Traits of a Good Network

The five main traits of a good network are:

• reliability

• scalable

• redundant

• secure

• speed

reliable network A dependable network that user’s trust to work. (p. 8)

scalable network A network that the hardware or software can grow (scale) up or down to meet an organization’s needs. (p. 9)

redundant network Networks that duplicate data and/or resources to minimize down time and losses in the event of a disaster. (p. 9)



A server cluster acts as a single server to other computers on the network.



The speed of a network is critical. Network speed is measured by several factors, such as the rate at which data will travel, which is related to its throughput.

throughput The capacity to handle network traffic. A measure for network data transfer performance. (p. 10)

pp. 12-171.2 The Evolution of Networks

Guide to Reading

Main Ideas

Understanding how networks evolved in the past helps you to understand today’s technology. Future networks will enable us to connect almost anywhere, anytime, and faster than ever before.

Key Terms

multitask

timesharing

terminal

dumb terminal

ARPANET

hyperlink

distributed computing


The First Networks

The first computers could only perform one task at a time. Within a few years, computers were able to multitask and timeshare, which increased the computer’s productivity.

multitask A computer’s ability to work on more than one job at a time. The processor can turn its attention from one job to another if one is held up waiting for input or output. (p. 12)

timesharing In the early days of computers, the concept of running multiple jobs at the same time. The idea of switching the computer’s processing from one task to another and incorporating a main, or host, computer. (p. 12)


The First Networks

Timesharing allowed for direct human/machine interaction through terminals.

Terminals used with timesharing computers were known as dumb terminals.

terminal A device with a keyboard and a monitor that connects directly to a mainframe through a communications link or cable. The terminal requests information from the mainframe computer. (p. 13)

dumb terminal Computers consisting of keyboards for input and screens for output. They are wired directly to the host computer and have little or no processing power of their own. (p. 13)


ARPANET

The U.S. Department of Defense established ARPANET. ARPANET linked computers around the country and provided a data highway for military communications.

ARPANET The Advanced Research Projects Agency Network created in the 1960s made it possible for military and university computers to communicate long distances and to share files through an interconnected network. (p. 13)


ARPANET

ARPANET allowed host computers around the country to communicate with each other.


Today’s Networks

Networks have become a part of everyday life. The original Internet was primarily a text-based network.

Tim Berners-Lee developed the World Wide Web, using a graphic user interface (GUI) with hyperlinks to access information on the Internet.

hyperlink Text or image that “links” the user to another document when clicked. (p. 14)


Today’s Networks

Although the Web is only one part of the Internet, most users think they are the same thing.

• The Internet is hardware connected together to create a network.

• The Web includes software (browsers) that send information along the Internet’s hardware.


Today’s Networks

Networks are important parts of many facets of our lives, such as the following examples:

• business

• health care

• education

• leisure and recreation


Today’s Networks

New ways of using existing systems, like distributed computing, allow computers connected to a network to share resources.

distributed computing Using the processing power of thousands of idle computers to process large data sets. For example, it is the primary source of computing power for research into the human genome. (p. 15)


Today’s Networks

Example of Distributed Computing


Today’s Networks

Other important developments in networking in recent years have been:

• Next Generation Internet (NGI) and Internet2

• educational Webcasts

• collaborative health care

pp. 18-221.3 Networking Careers

Guide to Reading

Main Ideas

There are many career paths in networking. Although educational backgrounds for many career paths in networking are similar, on-the-job experience and a continued interest in learning are keys to success in networking.

Key Terms

network administrator

network engineer

network architect

network support technician

outsourcing


Career Paths

There are many careers tied to networks and networking.

• network administrator

• network engineer

network administrator Trained individual responsible for installing computers and their operating systems and managing networks on a daily basis. (p. 18)

network engineer Highly trained individual responsible for connecting computers to the network and connecting networks to networks. (p. 19)


Career Paths

• network architect• network support technician

Some companies outsource their networking needs to contractors.

network architect Highly trained individual who oversees the construction, maintenance, and expansion of a company’s network. (p. 19)

network support technician Individual with specialized technical knowledge to troubleshoot the many problems that arise in network usage. (p. 20)

outsourcing To hire an outside company to handle various information technology (IT) services, such as technical support. (p. 20)


Job Skills

The job skills required to succeed in a networking career are communication, problem solving, teamwork, and leadership.

Because the technology is always changing, you can no longer count on going to college and learning all you will ever need to know for the rest of your career.


You Try It

• Activity 1A Creating a Career Development Plan (p. 22)

pp. 24-281.4 The Computer System

Guide to Reading

Main Ideas

A computer is made up of many components that interact with each other. Hardware is the physical components of the system. Software is a compiled set of instructions that tell the hardware what to do.

Key Terms

input

output

operating system (OS)

central processing unit (CPU)

reduced instruction set computers (RISC)

complex instruction set computers (CISC)

random-access memory (RAM)

read-only memory (ROM)


The Parts of a Computer System

It is very important in networking to understand how the different parts of a computer work together.

The four main parts of a computer system are:

• hardware

• software

• data

• users



Hardware identifies all the physical components of a computer.

Hardware is broken into several groups:

• input

• output

• storage devices

input Provides some sort of instruction to the computer so that it knows what to do. A device such as a keyboard is an example of an input device. (p. 24)

output Data that are displayed (for example, on a screen or printer) or heard as music from speakers. (p. 25)



Hardware devices allow users to interact with the computer.

A port, as shown in this figure, is a socket in the back of the computer. The port connects input and output devices to the computer.



The second part of the computer system is software. Software is a set of instructions for the computer processors. Software is often divided into two broad categories:

• systems software

• applications software



The third part of the computer system, data, is the information the computer works on.

Data are stored in binary format. As you input data, such as text, the operating system translates data into 1’s and 0’s so the computer can process and store the data.



The user is the fourth part of the computer system.

Users include the people who program computers, as well as those who use the applications.


Inside the Machine

Your computer is made of powerful hardware. The components in your computer include the following:

• processor

• memory

• communication devices


Inside the Machine

The central processing unit (CPU) is the brain of the computer. CPUs fall into two groups:

• RISC

• CISC

central processing unit (CPU) The brain, or processor component, of the computer that performs basic functions. (p. 27)

reduced instruction set computers (RISC) A type of microprocessor that relies on a relatively small set of simplified instructions, allowing them to operate very fast. (p. 27)

complex instruction set computers (CISC) A type of microprocessor that supports most instructions and is difficult to design and build, leading to somewhat higher costs. (p. 27)


Inside the Machine

Memory consists of two types:

• random-access memory (RAM)

• read-only memory (ROM)

random-access memory (RAM) Provides a storage area for data going into and out of the CPU. (p. 28)

read-only memory (ROM) A set of prerecorded instructions that tells the computer how to start, look for hardware devices, and check the operating system. (p. 28)


Inside the Machine

Communication devices, such as modems and network interface cards (NICs), enable your computer to connect to other computers.

NICs allow your computer to communicate with other computers on other networks.


You Try It

• Activity 1B Analyzing a Hard Drive (p. 26)

Chapter 1

Resources

For more resources on this chapter, go to the Introduction to Networks and Networking Web site at http://networking.glencoe.com.

http://networking.glencoe.com/



Documents

Section 1.1 Explain the reasons for using a network Show how networks are useful Describe the difference between synchronous and asynchronous networking