module 4 maintain computer systems and networks

8/10/2019 Module 4 Maintain Computer Systems and Networks

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PC HARDWARE SERVICINGThe Strengthened Technical-Vocational Education Program

Course : Computer Hardware Servicing NC IInit o! Competenc" : #aintain Computer S"stem and

Networ$s#odu%e : #aintaining Computer S"stem and

Networ$s

&earning 'utcome (: P%an and Prepare #aintenance Procedures

Assessment Criteria:

Planning and preparing for maintenance task is organized as a

prerequisite.

1. OHS policies are carried out along with the task.2. Computer system is regularly checked in compliance with

maintenance procedures.. !ppropriate materials are used for ensuring work deli"ery that

conforms with task speci#cations.$. Proper tools% equipment and testing de"ices for maintenance

purposes are o&tained and checked against correct operation andsafety.

'. Computer system and network are maintained &ased on themanual instructions

Re!erences:

1. (igelow% Stephen ).%PC Technicians Troubleshooting, McGraw

Hill2. *elly%+ianne,ose% Computer -aintenance and rou&leshootingHand&ook Rose Ne%son/0( httphome.comcast.net3

3. Sandler%Corey% 4i5 6our Own PC%-7S Press

4. *uhlman% +a"e% dkuhlman8re55.comhttpwww.re55.com3dkuhlman+a"e *uhlman. hisdocumentation is co"ered &y he -7 9icensehttpwww.opensource.orglicensesmit:license

5. -eyers%-ike%7ntroduction to PC Hardware androu&leshooting%-cgrawHill

6. www.eser"iceinfo.com

. httpcsd2.computer.org

!. httpse"ier.comwps

". www.yahoo.com

(; P a g e
http://home.comcast.net/~DianneRoseKellymailto:[email protected]://www.rexx.com/~dkuhlmanhttp://www.opensource.org/licenses/mit-licensehttp://www.eserviceinfo.com/http://www.yahoo.com/http://home.comcast.net/~DianneRoseKellymailto:[email protected]://www.rexx.com/~dkuhlmanhttp://www.opensource.org/licenses/mit-licensehttp://www.eserviceinfo.com/http://www.yahoo.com/


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P%an and Prepare #aintenance Procedures

Introduction:

Planning and preparing systematic maintenance procedure sa"e

time% money and frustration. 7t is a good idea and opportunity to learn

the proper care and maintenance of your computer.

PC maintenance is an important topic for anyone who owns a PC.

9ooking after your PC properly ensures you of trou&le:free use. ,egularPC maintenance also keeps the machine


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,NE ,&* AG SEP) 'C) N'V DEC

!nti "irus software

checkups

+isk spaceutilization+efragmentation of

hard dri"es

rou&leshoot

hardware and

software issues

)*PES '- #AIN)ENANCE PR'CEDRE:

.(/ Hardware maintenance is the testing and cleaning of equipment.

.+/ 7nformation system maintenance is the routine updating of master#les% such as adding and deleting employees and customers andchanging credit limits and product prices.

.0/ Software or program maintenance is the updating of applicationprograms in order to meet changing information requirements% suchas adding new functions and changing data formats. 7t also includes#5ing &ugs and adapting the software to new hardware de"ices.

.1/ +isk or #le maintenance is the periodic reorganizing of disk #les that

ha"e &ecome fragmented due to continuous updating.

Wor$ p%ace procedures

7dentify hazards and assess risk.

05ecution of OHS policies are carried out along with the task.

4ollowing certain procedure is "ery important to perform a gi"en

operation or e"olution or in reaction to a gi"en e"ent. he ta&le &elow

shows di>erent elements and their corresponding performance criteria to&e a&le to identify occupational health and safety hazards% and assess

risk% as well as follow instructions and procedure in the workplace with

minimal super"ision. he students will also &e capa&le of participating

and contri&uting to OHS management issues.

E&E#EN) PER-'R#ANCE CRI)ERIA

1. 7dentify hazards and

assess risk.

1.1 7dentify hazards in the work

area and during the

performance of workplace

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duties.

1.2 !ssess le"el of risk

2. 4ollow procedures andstrategies for risk

control.

2.1 ,eport hazards in the workarea to designated personnel

according to workplace

procedures

2.2 4ollow workplace procedures

and work instructions for

assessing and controlling

risks with minimal

super"ision.

2. /hene"er necessary% withinthe scope of responsi&ilities

and competencies% follow

workplace procedures for

dealing with hazards and

incidents% #re andor other

emergencies.

. Contri&ute to OHS in the

workplace.

.1 +escri&e employee


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.' Pro"ide support in

implementing procedures to

control risks in accordance

with organisational

procedures

05amples of OHS issues

which may need to &e

raised &y workers with

designated personnel may

include

7denti#ed Hazards

Pro&lems encountered in

managing risks associated

with hazards

Clari#cation on

understanding of OHS policiesand procedures

Communication and

consultation processes

4ollow up on reports and

feed&ack.

0>ecti"eness of risk controls

in place

raining needs

-aterials% ools% 0quipment and esting +e"ices.

Programming )oo%s

.(/ Programming tools are used for software de"elopment orsystem maintenance. Birtually% any program or utility that helps

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programmers or users de"elop applications or maintain theircomputers can &e called a tool. 05amples of programming tools arecompilers% interpreters% assem&lers% $9s% editors% de&uggers andapplication generators.

.+/ Programming tools help the user analyze or search for data.

4or e5ample% query and report programs are often called querytools and report tools.

.0/ !n on:screen function in a graphics programD for e5ample%line draw% circle draw or &rush tool.

.1/ ! software control panel for setting user preferences.

.2/ Sometimes people will call any software a Etool.E 4ore5ample% the phrase% Ethere arenFt any tools to do that Ao&E meansthat no application is a"aila&le to perform the required processing.

E3uipment4-aci%ities )oo%s 5 Instruments Supp%ies 5

#ateria%s

Ser"er

Computer peripherals

+esktop computers

OHS guidelines

Phil. 0n"ironmental

protection standards

-onitors

-other&oard

Power supply

=etwork de"ice and

ca&lings

Hu&s

Switches

9!= Cards

Printers and

Scanners

,outers

?S( 4lash +ri"es

Protecti"e eye wear

/ire stripper with

cutter

PliersG!ssorted

Screw dri"ers

G!ssortedSoldering irongun

+e:soldering tool

4lashlight

weezers

-irrors

!ntistatic wrist wrap

9!= ester

Crimping tool

Software installer

/ork &ench

-agnifying glass

4loppy disk

Compact +isk

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P%an and Prepare #aintenance Procedure

1. Prepare+esign a daily maintenance plan for your hardware% G time

allotment 1 week

#AIN)ENANCE )AS7 #'N )E WED )HR -RI

,ecali&rate the &attery

Clean computer case

Clean the key&oard

Clean the mouse

Clean the screen

Clean up hard dri"es

2. +esign a systematic daily plan for your software% G time allotment 1week

#AIN)ENANCE )AS7 #'N )E WED )HR -RIDA*

Create an emergency diskette

Check for "iruses

(ack up #les

+efragment hard dri"e

Scan hard dri"e for errors

Program course Computer Hardware Servicing NCII

?nit of Competency #aintain Computer S"stem and Networ$s

8; P a g e


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-odule #aintaining Computer S"stem and

Networ$s

&'9+ : #aintain Computer S"stem and Networ$s

Assessment Criteria:1. !ppropriate personal protecti"e equipment are used in conformity

with the standard procedures.2. Periodic maintenance of the equipment is performed following

manufacturer


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Re!erence:

1.-c9aughlin%,o&ert% Sasser%Susan% ,alston%-ary.4i5 6our OwnPC.Philippine raphic !rts% 7nc andang Sora St.Caloocan City

2.-eralco 4aoundation. -icrocomputer Ser"icing Plus. Pasig City%Philippines.

3.9egaspi%Carlos% CaiIa% -ark !nthony. Operate ! Personal Computer.+asmariIas Computer 9earning Center.+asmariIas%Ca"ite%Philippines

4.(igelow%Stephen ). PC echnicianworks.com

9.www.microsoft.comtechnetnetwork

ools and equipment used to protect the user and the computer system.

ypes of personal protecti"e de"ices

1. !nti:static de"ices

2. Power surge protectors

. Personal equipments

ESD .E%ectro Static Disc;arge/

:! small amount of static electricity that can destroy small parts of yourcomputer.

Anti


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2. ?PS G?ninterrupted Power Supply

Persona% E3uipment

1. Small paint &rush

2. Screw dri"ers

. Pliers and tweezers

$. Compressed air

'. Handheld "acuum

Periodic #aintenance Sc;eme

,egular scheduled upkeep of your computer will keep you and your

computer in working smoothly.

Dai%" Sc;edu%e

?pdate "irus and spyware de#nitions

+o incremental &ackup J &ack up updated #les for each date.

,e&oot upon crash: ,e&oot the computer to #5 your pc upon crash.Wee$%"

4ull "irus and spyware scan

Complete &ackup of #les

Patch up Jet latest software update for your operating system.#ont;%"

Clean your PC inside and out.

+efrag your hard dri"e to speed up its operation.*ear%"

Check your programs J clean up unused programs

,eformat your hard dri"e and reinstall the operating system

-ake a full diagnostic check on hardware and softwareSamp%e #aintenance sc;eme

Preventive #aintenance Activit"Recommended

-re3uenc"Auto>

Scan ;ard dis$ ?%e s"stems !orerrors

+aily 6es

Scan !or viruses +aily 6es

(@; P a g e
http://www.pcguide.com/care/data/det_Scanning.htmhttp://www.pcguide.com/care/data/det_Scanning.htmhttp://www.pcguide.com/care/data/virus/scan.htmhttp://www.pcguide.com/care/data/det_Scanning.htmhttp://www.pcguide.com/care/data/det_Scanning.htmhttp://www.pcguide.com/care/data/virus/scan.htm


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ac$ up data +aily =o

C%ean CR) screen /eekly =o

De!ragment ;ard dis$s -onthly 6es

Scan !or ;ard dis$ read errors /eekly 6es

C%ean mouse -onthly =o

C;ec$ !or !u%% ;ard dis$ vo%umes

and remove unnecessar" ?%es -onthly =o

pdate virus de?nition ?%es -onthly Sometimes

C;ec$ power protection devicesto ensure t;e" are sti%%protecting t;e s"stem

Kuarterly =o

C;ec$ power supp%" !an !orventi%ation and dirt Bui%dup and

c%ean i! necessar"Kuarterly =o

ac$ up C#'S in!ormation Kuarterly =o

pdate emergenc" Boot oppies Kuarterly =o

C%ean opp" dis$ drive interna%s

and read4write ;eads

Kuarterly

Gdepending onuse =o

C;ec$ processor temperatureinspect ;eat sin$ and !an to

ensure t;e" are wor$ing

!nnually Gorwhene"er case is

opened=o

C;ec$ ;ard dis$ !or temperatureand viBration

!nnually Gorwhene"er case is

opened=o

((; P a g e
http://www.pcguide.com/care/bu/index.htmhttp://www.pcguide.com/care/care/comp_Monitors.htmhttp://www.pcguide.com/care/data/prev_Defragmentation.htmhttp://www.pcguide.com/care/data/det_Detecting.htmhttp://www.pcguide.com/care/care/comp_Mice.htmhttp://www.pcguide.com/care/data/prev_Cleaning.htmhttp://www.pcguide.com/care/data/prev_Cleaning.htmhttp://www.pcguide.com/care/data/virus/scan_Files.htmhttp://www.pcguide.com/care/care/comp_Power.htmhttp://www.pcguide.com/care/care/comp_Power.htmhttp://www.pcguide.com/care/care/comp_Power.htmhttp://www.pcguide.com/care/care/comp_Power.htmhttp://www.pcguide.com/care/care/comp_Power.htmhttp://www.pcguide.com/care/care/comp_Power.htmhttp://www.pcguide.com/care/bu/what_BIOS.htmhttp://www.pcguide.com/care/bu/boot_Updating.htmhttp://www.pcguide.com/care/care/comp_FDD.htmhttp://www.pcguide.com/care/care/comp_FDD.htmhttp://www.pcguide.com/care/care/comp_Processor.htmhttp://www.pcguide.com/care/care/comp_Processor.htmhttp://www.pcguide.com/care/care/comp_Processor.htmhttp://www.pcguide.com/care/care/comp_HDD.htmhttp://www.pcguide.com/care/care/comp_HDD.htmhttp://www.pcguide.com/care/bu/index.htmhttp://www.pcguide.com/care/care/comp_Monitors.htmhttp://www.pcguide.com/care/data/prev_Defragmentation.htmhttp://www.pcguide.com/care/data/det_Detecting.htmhttp://www.pcguide.com/care/care/comp_Mice.htmhttp://www.pcguide.com/care/data/prev_Cleaning.htmhttp://www.pcguide.com/care/data/prev_Cleaning.htmhttp://www.pcguide.com/care/data/virus/scan_Files.htmhttp://www.pcguide.com/care/care/comp_Power.htmhttp://www.pcguide.com/care/care/comp_Power.htmhttp://www.pcguide.com/care/care/comp_Power.htmhttp://www.pcguide.com/care/care/comp_Power.htmhttp://www.pcguide.com/care/care/comp_Power.htmhttp://www.pcguide.com/care/care/comp_Power.htmhttp://www.pcguide.com/care/bu/what_BIOS.htmhttp://www.pcguide.com/care/bu/boot_Updating.htmhttp://www.pcguide.com/care/care/comp_FDD.htmhttp://www.pcguide.com/care/care/comp_FDD.htmhttp://www.pcguide.com/care/care/comp_Processor.htmhttp://www.pcguide.com/care/care/comp_Processor.htmhttp://www.pcguide.com/care/care/comp_Processor.htmhttp://www.pcguide.com/care/care/comp_HDD.htmhttp://www.pcguide.com/care/care/comp_HDD.htm


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C%ean eterior o! case !nnually =o

C%ean eterior o! monitor !nnually =o

C;ec$ and c%ean interiormot;erBoard and epansion

cards i! necessar"!nnually =o

C;ec$ interna% connections andcaB%es

!nnually =o

!nnually =o

Answer t;e !o%%owing 3uestions

1. 4or some&ody who always works with computers% what personal

protecti"e de"ices do you usually useL How often do you usethemL2. Computers should &e protected from static electricity to pre"ent

component malfunction. /hat anti:static de"ices can you utilize toa"oid such malfunctionL

(+; P a g e
http://www.pcguide.com/care/care/comp_Case.htmhttp://www.pcguide.com/care/care/comp_Monitors.htmhttp://www.pcguide.com/care/care/comp_Motherboard.htmhttp://www.pcguide.com/care/care/comp_Motherboard.htmhttp://www.pcguide.com/care/care/comp_Motherboard.htmhttp://www.pcguide.com/care/care/comp_Motherboard.htmhttp://www.pcguide.com/care/care/comp_Motherboard.htmhttp://www.pcguide.com/care/care/comp_Case.htmhttp://www.pcguide.com/care/care/comp_Monitors.htmhttp://www.pcguide.com/care/care/comp_Motherboard.htmhttp://www.pcguide.com/care/care/comp_Motherboard.htmhttp://www.pcguide.com/care/care/comp_Motherboard.htmhttp://www.pcguide.com/care/care/comp_Motherboard.htmhttp://www.pcguide.com/care/care/comp_Motherboard.htm


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C%eaning t;e #ouse

1. Shut down the PC &efore cleaning the mouse.2. ,oll the mouse o"er onto its &ack and remo"e the &all access slide

co"er.. /ash the mouse &all with water.$. 7nspect the mouse &all


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C%eaning t;e #onitor

1. urn o> the monitor and unplug it from the power source.2. ?sing compressed air% clean away any dust on the top of the

monitor


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Procedure in c%eaning t;e $e"Board

1. Shut down the computer and turn o> the computer.2. +isconnect the key&oard from the computer and lay it upside:down

on a at% clean work surface.. ,emo"e the screws that hold together the key&oard case.$. Holding the case together% turn the key&oard o"er% and then

remo"e the top co"er. ?se the compressed gas andor &rush and"acuum to clean out the keys.

'. aking care not to dislodge any keys% remo"e the key assem&lyfrom the case.

M. 7f the key&oard has a circuit card attached to the key assem&ly%remo"e it and set it aside.

N. ,emo"e the screws that hold the &ack metal plate to the keyassem&ly. Put the screws in a cup or another container so youwon the metal plate. /hat you #nd underneath dependson the design of the key&oard. Carefully lift and clean the contacts

on the card with the alcohol and cloth.Q. Pro&a&ly% there will &e some type of ru&&er pad &etween theprinted circuit and the &ack of the keys. Carefully lift this up andclean any spill residue from the pad as well as the &acks of thekeys.

1R. ,eassem&le the pads% printed circuit% circuit card and metal plate%and then turn the assem&ly right:side up again.

11. 7t would &e a good idea to remo"e the keys and clean them% aswell. hey should pop o>. )ust don


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Printer C%eaning

In$Fet Printer

1. Clean the print nozzle regularly. -ost inkAet printers ha"e a &uilt:inutility to clean or unclog the print head nozzles. 6ou should do thisregularly% especially if the printer sits idle for a couple of weeks.

2.=e"er turn a printer o> &y pulling the plug from the power source.

!lways use the printer. he printer hassome &uilt:in functions% such as parking the print head that aretied to the power:o> function of the printer switch.

. ?se inkAet quality paper.$.+ust and paper scraps and &its can collect in the &ottom of the

paper path in an inkAet printer. ,emo"e the paper scraps and &lowout any dust or paper &its that ha"e accumulated withcompressed air.

C%eaning "our s"stem unit

Cleaning the system unit and its parts is not really dicult to doD you Aust

need the proper tools to clean it properly. ?sing compressed air antistatic

strap and a Phillips screw dri"er you can e>ecti"ely clean your unit

he parts that need cleaning are the >

1. -other&oard

2. -emory. 7nterface cards

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$. Hard dri"es'. Optical +ri"esM. System Case

Computer Hardware #aintenance and C%eaning

E3uipment and #ateria%s:

E3uipment

System unit

-onitor

*ey&oard and -ouse

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Printer

#ateria%s

Screw dri"er

!ir Compressor

!nti:static Strap

Computer Hardware Maintenance and Cleaning

he student is pro"ided with the necessary equipment and materials toclean the di>erent hardware components of a computer unit.

6ou will &e assessed using the following criteria

Eva%uation:

CRI)ERIAPassed -ai%ed

1. Periodic maintenance is o&ser"ed

2. O&ser"ance of safety precautions.

. !ppropriate materials are used in cleaning thehardware components.

$. Con#rmation of computers normal function.

Write "our answers on "our answer s;eet:

1. 0numerate the &asic tools needed in cleaning your system unit.

2. Can we use anti:static glass cleaner when cleaning the monitorL

6es or =o. /hyL

. 7s it safe to clean your printer when it is still onL 05plain.

$. /hy do we need to shutdown our computer unit &efore we clean

and disassem&leL

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Computer Virus

! "irus is a destructi"e e5ecuta&le program that

infects the other programs in the systemandspreads &y replicating itself.

Such a program is designed to damage the"ictim


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designs the "irusFs attack phase% whether itFs a silly message or

destruction of a hard disk. So why do people do itL

here are at least three reasons. he #rst is the same psychology

that dri"es "andals and arsonists. /hy would someone want to &ust the

window on someone elseFs car% or spray:paint signs on &uildings or &urndown a &eautiful forestL 4or some people% that seems to &e a thrill. 7f that

sort of person happens to know computer programming% then he or she

may funnel energy into the creation of destructi"e "iruses.

he second reason has to do with the thrill of watching things &low

up. -any people ha"e a fascination with things like e5plosions and car

wrecks. /hen you were growing up% there was pro&a&ly a kid in your

neigh&orhood who learned how to make gunpowder and then &uilt &igger

and &igger &om&s until he either got &ored or did some serious damage

to himself. Creating a "irus that spreads quickly is a little like that :: it

creates a &om& inside a computer% and the more computers that get

infected the more EfunE the e5plosion.

he third reason pro&a&ly in"ol"es &ragging rights% or the thrill of

doing it. Sort of like -ount 0"erest. he mountain is there% so someone is

compelled to clim& it. 7f you are a certain type of programmer and you

see a security hole that could &e e5ploited% you might simply &e

compelled to e5ploit the hole yourself &efore someone else &eats you to

it.raditional computer "iruses were #rst widely seen in the late

1QRs% and they came a&out &ecause of se"eral factors. he #rst factor

was the spread of personal computers GPCs. Prior to the 1QRs% home

computers were nearly non:e5istent or they were toys. ,eal computers

were rare% and they were locked away for use &y Ee5perts.E +uring the

1QRs% real computers started to spread to &usinesses and homes

&ecause of the popularity of the 7(- PC Greleased in 1Q2 and the !pple

-acintosh Greleased in 1Q$. (y the late 1QRs% PCs were widespread in

&usinesses% homes and college campuses.

+@; P a g e
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The secon# $actor is the use o$ co%&uter bulletin boar#s. Peo&le

coul# #ial u& a bulletin boar#with a %o#e%an# #ownloa# &rogra%s

o$ all t'&es. Ga%es are e(tre%el' &o&ular, an# so are si%&le wor#

&rocessors, s&rea#sheets, etc. )ulletin boar#s lea# to the &recursor

o$ the *irus +nown as the Troan horse. - Troan horse is a &rogra%that soun#s reall' cool when 'ou rea# about it. o 'ou #ownloa# it.

/hen 'ou run the &rogra%, howe*er, it #oes so%ething uncool li+e

erasing 'our #is+. o 'ou thin+ 'ou are getting a neat ga%e, but it

wi&es out 'our s'ste%. Troan horses onl' hit a s%all nu%ber o$

&eo&le because the' are #isco*ere# 0uic+l'. ither the bulletin

boar# owner woul# erase the le $ro% the s'ste% or &eo&le woul#

sen# out %essages to warn one another.

Diferent Aspects o Computer Virus

4inder: searches for the new uninfected #les and the

,eplicator: actually targets these #les and infects it &y multiplying itself.)"pes o! virus

Resident Viruses

his type of "irus is a permanent which dwells in the ,!- memory.

4rom there it can o"ercome and interrupt all of the operations

e5ecuted &y the system corrupting #les and programs that are

opened% closed% copied% renamed etc.05amples include ,ande5% C-)% -e"e% and -r*lunky.

Direct Action Viruses

he main purpose of this "irus is to replicate and take action when it is

e5ecuted. /hen a speci#c condition is met% the "irus will go into action

and infect #les in the directory or folder that it is in and in directories

that are speci#ed in the !?O0T0C.(! #le P!H. his &atch #le is

always located in the root directory of the hard disk and carries out

certain operations when the computer is &ooted.

'verwrite VirusesBirus of this kind is characterized &y the fact that it deletes the

information contained in the #les that it infects% rendering them

partially or totally useless once they ha"e &een infected.

he only way to clean a #le infected &y an o"erwrite "irus is to delete

the #le completely% thus losing the original content.

05amples of this "irus include /ay% rA.,e&oot% ri"ial..+.

oot Virus

his type of "irus a>ects the &oot sector of a oppy or hard disk. his

is a crucial part of a disk% in which information on the disk itself isstored together with a program that makes it possi&le to &oot Gstart

+(; P a g e
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the computer from the disk.

he &est way of a"oiding &oot "iruses is to ensure that oppy disks are

write:protected and ne"er start your computer with an unknown oppy

disk in the disk dri"e.

05amples of &oot "iruses include Poly&oot.(% !nti0T0.

#acro Virus

-acro "iruses infect #les that are created using certain applications or

programs that contain macros. hese mini:programs make it possi&le

to automate series of operations so that they are performed as a

single action% there&y sa"ing the user from ha"ing to carry them out

one &y one.

05amples of macro "iruses ,ela5% -elissa.!% (a&las% OQN-62*.

Director" Virus

+irectory "iruses change the paths that indicate the location of a #le.

(y e5ecuting a program G#le with the e5tension .0T0 or .CO- which

has &een infected &y a "irus% you are unknowingly running the "irus

program% while the original #le and program ha"e &een pre"iously

mo"ed &y the "irus.

Once infected it &ecomes impossi&le to locate the original #les.

Po%"morp;ic Virus

Polymorphic "iruses encrypt or encode themsel"es in a di>erent way

Gusing di>erent algorithms and encryption keys e"ery time they infect

a system.

his makes it impossi&le for anti:"iruses to #nd them using string or

signature searches G&ecause they are di>erent in each encryption and

also ena&les them to create a large num&er of copies of themsel"es.

05amples include 0lkern% -ar&urg% Satan (ug% and uareg.

-i%e In!ectors

his type of "irus infects programs or e5ecuta&le #les G#les with an

.0T0 or .CO- e5tension. /hen one of these programs is run% directly

or indirectly% the "irus is acti"ated% producing the damaging e>ects it is

programmed to carry out. he maAority of e5isting "iruses &elong to

this category% and can &e classi#ed depending on the actions that they

carry out.

Companion Viruses

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Companion "iruses can &e considered #le infector "iruses like resident

or direct action types. hey are known as companion "iruses &ecause

once they get into the system they EaccompanyE the other #les that

already e5ist. 7n other words% in order to carry out their infection

routines% companion "iruses can wait in memory until a program is runGresident "iruses or act immediately &y making copies of themsel"es

Gdirect action "iruses.

Some e5amples include Stator% !simo".1'Q% and erra5.1RMQ

-A) Virus

he #le allocation ta&le or 4! is the part of a disk used to connect

information and is a "ital part of the normal functioning of the

computer.

his type of "irus attack can &e especially dangerous% &y pre"enting

access to certain sections of the disk where important #les are stored.

+amage caused can result in information losses from indi"idual #les or

e"en entire directories.

Worms

! worm is a program "ery similar to a "irusD it has the a&ility to self:

replicate% and can lead to negati"e e>ects on your system and most

importantly they are detected and eliminated &y anti:"iruses.

05amples of worms include PS/(ug&ear.(% 9o"gate.4% rile.C% So&ig.+%

-apson.

)roFans or )roFan Horses

!nother unsa"ory &reed of malicious code are roAans or roAan horses%

which unlike "iruses do not reproduce &y infecting other #les% nor do

they self:replicate like worms.

&ogic omBshey are not considered "iruses &ecause they do not replicate. hey

are not e"en programs in their own right &ut rather camouaged

segments of other programs.

How do Virus Afect a System

7t corrupts #les 7t slows down the speed of the computer system

7t causes the system to hang frequently

7t deletes "arious #les

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Sources o Virus !nection

! "irus can enter the system and infect it through "arious sources. Someof the sources are

7nfected C+s% +B+s% pen dri"es% etc 0:mail

(rowsing infected sites

+ownloading #les from the internet

Steps to "emo#e Viruses

,emo"ing "iruses% though technical% is yet a "ery simple process if all therequired steps are properly followed.

he &asic steps are

(uy or download an anti"irus softwareG!B !nti:"irus 7nstall the anti"irus software

?pdate anti"irus software with the latest "irus de#nitions +o a complete system scan

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#et;ods o! E%iminating Viruses

,emo"ing the "irus J /hen the "irus can &e easily identi#ed and can &e

remo"ed without a>ecting other #les% then the anti"irus remo"es it from

the host place.

Kuarantine J his is done when the "irus cannot &e easily identi#edremo"ed from the #le and the remo"al of "irus means the remo"al of thecomplete #le. 7n this method% although the "irus is not eliminated% it isrendered inacti"e &y mo"ing the #le into EquarantineE and renaming it.

Anti


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Virus remova%

E3uipment and #ateria%s:

E3uipment

System unit

-onitor

*ey&oard and -ouse

#ateria%s

!nti:"irus Software G!ny !nti:"irus software

Birus remo"al

Pro"ided with the necessary equipment and materials trou&leshoot the"irus infected area.


Eva%uation:

CRI)ERIAPassed -ai%ed

1.Periodic maintenance is o&ser"ed

2. Safety precautions are o&ser"ed.

. !ppropriate materials are used in "irus remo"al.

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$. Computers =ormal function is con#rmed.

Program Course Computer Hardware Servicing NCII

?nit of Competency #aintain Computer S"stem and Networ$s

-odule #aintaining Computer S"stem and

Networ$s

9O. itle Inspecting and testing computer s"stem

and networ$s

Assessment Criteria:1. 4inal inspection of the de"ice is instituted to ensure task

perfection.

2. 9a&oratory management and maintenance are o&ser"ed toconform to company standard.

. !ccomplishment report is deli"ered to concerned teacher after#nishing the task.

Resources:

E3uipment4-aci%ities )oo%s 5 InstrumentsSupp%ies 5

#ateria%s

Ser"er

Computer peripherals

+esktop computers

OHS guidelines

Phil. 0n"ironmental

protection standards

-onitors

-other&oard

Protecti"e eye wear

/ire stripper with

cutter

PliersG!ssorted

Screw dri"ers

G!ssorted

Soldering irongun

+e:soldering tool

4loppy disk

Compact +isk

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Power supply

=etwork de"ice and

ca&lings

Hu&s

Switches

9!= Cards

Printers and Scanners

,outers

?S( 4lash +ri"es

4lashlight

weezers

-irrors

!ntistatic wrist wrap

9!= ester

Crimping tool

Software installer

/ork &ench

-agnifying glass

!llen key .R':.2'

7C insertione5traction

tool

,S:22 pin

insertione5traction tool

Re!erence:

1. -c9aughlin%,o&ert% Sasser%Susan% ,alston%-ary.4i5 6our OwnPC.Philippine raphic !rts% 7nc andang Sora St.Caloocan City

2. -eralco 4aoundation. -icrocomputer Ser"icing Plus. Pasig City%Philippines.

. 9egaspi%Carlos% CaiIa% -ark !nthony. Operate ! Personal Computer.+asmariIas Computer 9earning Center.+asmariIas%Ca"ite% Philippines

$. (igelow%Stephen ). PC echnician


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Computer S"stem and Networ$ Inspection

#ateria%s )oo%s and E3uipment

E3uipment:

2 Computer units

Printer

H?( Switch

-O+0-,outer

=etwork Ca&le

9!= ester

-ulti:tester

#ateria%s:

/indows TP C+ installer

/indows Q C+ installer

!nti:"irus Software

Computer -aintenance Software

Hardware Inspection

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i"en the following tools and equipment% perform hardware

inspection. Check the computers connection and con#guration and check

for the "oltage output of the power supply.

So!tware Inspection

i"en the following materials% perform software inspection.

Check for the >

1. Biruses2. ?nnecessary software. +ri"ers are installed

Networ$ Inspection

i"en the following tools% perform network inspection.

Check the >

1. 4ile and printer sharing2. 7nternet connection. Proper ca&le connection


Eva%uation:

CRI)ERIA Passed -ai%ed

1. Sequence of steps.

2. O&ser"ance safety precautions.

. Proper inspection of hardware components.

$. Proper inspection of the power supply.

Networ$ and Internet Inspection


Eva%uation:


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. Proper inspection of network components.

$. Proper inspection of network connection.

So!tware Inspection


Eva%uation:




. Proper inspection of operating system.

$. Proper "irus remo"al.

A!ter t;e inspection t;e student wi%% create an accomp%is;ment

report to Be suBmitted to t;e teac;er9

Accomp%is;ment report

Area to Be Inspected ood

running

condition

(ad

running

condition

,emarks

HARDWARE

S'-)WARE

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PC HARDWARE SERVICING

NE)W'R7

Answer $e" 89+9(

1. Personal protecti"e de"ices are the tools and equipment used toprotect the user and the computer system

2. !nti:static de"ices

!nti:static wrist strap

!nti:static mat

!nti:static &ag

!nti:static spray

Answer 7e" 89+9+

1. Compress !ir% Phillip Screw dri"er% !nti:static strap2. 6es. =o$. o a"oid the risk of electrical shock.

module 4 maintain computer systems and networks

Documents