CCNA

CISCO CERTIFIED NETWORK ASSOCIATE

Main Objectives

Understand the physical connection that has to take place for a computer to connect to the Internet.

Recognize the components that comprise the computer.

Install and troubleshoot network interface cards and/or modems.

Use basic testing procedures to test the Internet connection.

Demonstrate a basic understanding of the use of web browsers and plug-ins

Computer Basics

Small, Discrete Components

Personal Computer Subsystems

Backplane Components

Electronic Components

Capacitor stores energy in the form of an

electrostatic fieldConnector

the part of a cable that plugs into a port or an interface

Integrated circuit (IC) a device made of semiconductor

material; it contains many transistors and performs a specific task

Electronic Components

Light emitting diode a semiconductor device that

emits light when a current passes through it

Resistor a device made of a material

thatopposes the flow of electric current

Transistor a device that amplifies a

signal or opens and closes a circuit

Personal Computer Subsystems

Bus collection of wires through which data is

transmitted from one part of the computer to another; connects all the internal computer components to the CPU (ISA and PCI)

CD-ROM drive a compact disk read-only memory drive; a

device that can read information from a CD-ROM

Central processing unit (CPU) the brains of the computer where most

calculations take place

Personal Computer Subsystems

Expansion card a printed circuit board you can insert into a

computer to give it added capabilitiesExpansion slot

an opening in a computer where acircuit board can be added

Floppy disk drive a disk drive that can read or write to floppy disks

Hard disk drive a device that reads and writes data on a hard

disk

Personal Computer Subsystems

Microprocessor a silicon chip that contains a CPU

Motherboard the main printed circuit board of a

microprocessorPower supply

the component that supplies the power to a computer

Printed circuit board (PCB) a thin plate on which chips (ICs) and other

electronic components are placed

Personal Computer Subsystems

Random access memory (RAM) RAM can have new data written into it and

stored data read from it; a drawback of RAM is that it requires electrical power to maintain data storage

Read-only memory (ROM) computer memory on which data has

been prerecordedSystem unit

the main part of a PC; the system unit includes the chassis, the microprocessor, the main memory, the bus, and the ports

Hard drive interfaces

interface is the way the drive communicates with the computer; a sort of language that allows the drive and the computer to talk to each other IDE, SCSI

most controller circuitry is placed directly on the hard drive

Modems

modem converts digital data from its local computer into analog tones and pulses that can be sent over the telephone lines

two basic types--internal/external

The Power Supply

converts AC from wall outlet to DC used by computers

contains fan and AC/DC converter

Backplane Components

Backplane the large circuit board that

contains slots for expansion cards

Interface a piece of hardware such as a

modem connector that allows two devices to be connected

Mouse port a port designed to connect a

mouse to a PC

Backplane Components

Network card an expansion board inserted into a

computer so that the computer can be connected to a network

Parallel port an interface capable of transferring more

than one bit simultaneously; used to connect external devices such as printers

Port an interface on a computer to which you

can connect an electronic device

Backplane ComponentsPower cord

a cord used to connect computer to electrical outlet

Serial port an interface that can be used for serial

communi-cation in which only one bit is transmitted at a time

Sound card an expansion card that handles all sound

functionsVideo card

a board that plugs into a PC to give it display capabilities

Information FlowInformation and electric power are constantly flowing in a PC.

Boot instructions—stored in ROM until they are sent out

Software applications—stored in RAM after they are loaded

RAM and ROM—constantly talk to the CPU through the bus

Application information—stored in RAM while applications are being used

Saved information—flows from RAM to some form of storage device

Exported information—flows from RAMand the CPU through the bus and expansion slots to the printer, the video card, the sound card, or the network card

An Idealized Computer

What’s in that box?

Inside a Computer

An Idealized Computer: Information Flow

Network Interface Cards

printed circuit board that provides network capability to computer

also called a LAN adapter

can be designed as an Ethernet, Token Ring, or FDDI card

Network Interface Cards

communicate through a serial connection

Each card requires an IRQ, an I/O address, and an upper memory address to work with DOS/WIN95.

To configure TCP/IP LAN settings in a Windows machine, use the Control Panel icon, Network.

Network Interface CardsConsiderations:

type of network (Ethernet, Token Ring, FDDI)

type of media (CAT5, fiber, wireless)

type of system bus either PCI/ISA or PCMCIA, which is used on laptops)

To change a PCs network speed from 10Mbps to 100Mbps, you need to upgrade the NIC.

TCP/IP

Transmission Control Protocol/Internet Protocol (TCP/IP) is a set of protocols or rules developed to allow cooperating computers to share resources across a network. To enable TCP/IP on the workstation, it must be configured using the operating system tools. The process is very similar whether using a Windows or Mac operating system.

TESTING CONNECTIVITY

The ping command works by sending multiple IP packets to a specified destination. Each packet sent is a request for a reply. The output response for a ping contains the success ratio and round-trip time to the destination. From this information, it is possible to determine if there is

connectivity to a destination. ping 127.0.0.1 Ping 195.14.130.220

Web Browsers

Plug-ins allow the browser to display proprietary file types.

Plug Ins

Flash/Shockwave

Troubleshooting Internet connection problems

Define the problemGather the factsConsider the possibilityCreate action planImplement planObserve resultsDocument results

Binary Number System

Computer systems only understand “on” and “off” or “1s” and “0s.”

Computer systems use a binary numbering system rather than decimal.

Decimal numbering system uses 10 symbols; they are 0-9.

Computer systems use a Base 2 system.

27 26 25 24 23 22 21 20

128

64 32 16 8 4 2 1

8 bits = 1 byte

A bit is a binary digit used in the binary numbering system, either 0 or 1.

Binary Number System

Binary Number System

The binary number 10010001 in Base 2 = 145.

27 26 25 24 23 22 21 20

128 64 32 16 8 4 2 1

1 0 0 1 0 0 0 1

(1, 128) = 128 + (0, 64) = 0 + (0, 32) = 0 + (1, 16) = 16 + (0, 8) = 0 + (0, 4) = 0 + (0, 2) = 0 + (1, 1) = 1 = 145

Binary Number System

The decimal number 35 in Base 2

27 26 25 24 23 22 21 20

128 64 32 16 8 4 2 1

0 0 1 0 0 0 1 1

Binary Number System

If the right-most digit is odd, then the number is odd. (255)

27 26 25 24 23 22 21 20

128 64 32 16 8 4 2 1

1 1 1 1 1 1 1 1

Binary Number System

If the right-most digit is even, then the number is even. (142)

27 26 25 24 23 22 21 20

128 64 32 16 8 4 2 1

1 0 0 0 1 1 1 0