Giáo trình dành cho kỹ sư cntt cơ bản

I TRUNG TAM SAT HACH CONG NGHE THONG TIN VA HO TRO DAO TAO
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ViTEC

GIAO TRINH DANH CHO KY SIT CNTT CO BAN
Tai lieu

hanh noi bo
Ban a

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PHAT TRIEN VA VAN HANH HE THONG
m

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Muc sue
■

*

Mac lye...............................¥................................ ..................................................................................................................................................■;
Gi-Vi thieu ....................................................................................... ........................................................................................................................... ’
1

Phat trien he thong...........................................................................................................................................................................................'
ji6i th ieu ................................................. ......... ................................................................................................................................................
1.1

Phuong phap lu$n Phat trien he thong..........................................................................................................................................

1.1.1

Vai tro cua to chuc phat trien he thong.............................................................................................................8

1.1.2

Mo hinh phat trien phan mem.............................................................. ............................................................10

1.1.3

V6ng d6i phan m em .................................................. ................................................... ......................................16

1.1.4

Dung lai Phan m em ............................................................................................................................ ....t......... 25
Phan tfch yeu cau vh phuong phap thiet k e................................................................................................................................2;

12
1.2.1

Phuong phap l^p bieu do................................................................................... ................................................28

1.2.2

Lap bieu do phan ti'ch/thi£'t ke...........................................................................................................................30

1.2.3,

Phuong ph&p thiet k£'.......................................................................................................................................... 37

13

Ngon ngu l$p trinh.............................................................................................................................................................................5.

1.3.1

Thupc tinh chuong trinh................................................................................ ................................................ 57

1.3.2

Kieu du lieu......................................................................................................... ................................................ 58

1.3.3

Cau true dieu khien.......................................................................................... .................................................59

1.3.4

Phan tich cu phap............................................................................................................................................... 61

1.3.5

Phan lo^i ve ngon ngu* lap trinh...................................................................

1.3.6

Kieu va d&c trung cua ngon ngu lap trinh.................................................................................................. 70

11

Ky thuat lap trinh............................................................. ........................................................................................................

1.4.1

Lap trinh thu tyc........................................................................................................................... ........................77

1.4.2

I ap trinh h am ......................................................................................................... .............................................. 77

. 1,4.3

-

1- ô?p frinK iojằk - ã

ã

. ...................................................................... 78


2

1.4 4

1.5

Lap trinh huong doi Uft/ng

.............. .................... ................................ .........................................................79

Phuong phap kiem thtr va kiem diem............................................................................. .................................................................80

1.5.1

Phuong phap kiem thtr............................................................................................................................................ W

i .5.2

Phirong phap ki£m diem................................ ....................................................................................................... S7

1.5.3

Thiet ke kiem thu va phuong phap quan ly .................................................................................................... 90

1.6

Moi truong phat trien.............................................................................................................................................................................. 93

1.6.1

Cong cm ho Uq phat trien........................................................... ...........................................................................93

1.6.2

E U C v a E U D ..........................................................................................................................................................100

1.7

Quan ly phat trien............................................................................................................................................................................... 102

1.7.1

L?p ke hoach d y an............................................................................................................................................. 102

1.7.2

L|p ke ho$ch, quan ly va danh gia chat luong.............................................................................................. 102

1.7.3

Quan ly tien trinh....................................................................................................................................................105

1.7.4

Nang suat phan mem..............................................................................................................................................109

1.7.5

To chuc phat trien ......... ........................................................................................................................................ 113

1.8

G6i phan m em ....................................................................................................... ............................................................................... .119

1.8.1

D$i cuong ve goi phan mem................................................................................... t......................................119

1.8.2

Phan lo^i cac goi phan m em ...............................................................................................................................120

1.8.3

Cong cy quan ly san xu at..................................................................................................................................... 121

1.8.4

Vi dy ve viec dimg hieu qu£ goi phan mem..................................................................................................122

1.8.5

Phan mem nh6m - Groupware.................................................................................................... ....................... 123

1.8.6

Cong cy O A ................................................................................................................................................................124

Bai t?p ..................................................................................................................................................................................................................... 129
2

V£n hanh va bao tri he thong....................................................................................................................................................................135
Gjoi thi£u ............................................................................................................................................................................................................... 136
2.1

Van hanh he thong.................................................................................................................................................................................137

2.1.1

Quan ly tai nguyen..................................................................................................................................................137

2.1.2

Quan Iv van de............................................................................................................................... ......................... 139

2.1.3

Quan ly tien nghi................................................................................................................................................... 141

2.1.4

Quan ly an ninh........................................................................................................................................................ 143


3

z. 1.6
.2. i./

ly du p h i......... ... ........ ...............
ui.icii'i ly

KdilLi KiiuC......................................................................... ......................... *....................... i46

8 £ j tri he thong ...... ............................................................................................... ....................................................................... 148

2.2
2.2.1

Bao tri la gi?..............................................................................................................................................................148

2.2.2

Tam quan trongcua cong vif c bao tr i..............................................................................................................149

2.2.3

Chi phi bao tri.................................... ............................................................ ,................ ................................... 149

2.2.4

Nhifm vy bao tri....................................................................................................................................................150

2.2.5

To chuc bao tri........................................................................................................................................................154

2.2.6

Cac kieu b£o tri...................................................................................................................................................... 157

2.2.7

Bao tri phan cung va M o tri phan mem....................................... . ............. .............

.

....... ........ 158

Bai tip ................ .................................................................................................................................................................................... ...............161
C?p nhit x u ly thong tin va an ninh........................................................................................................................................................164
Gidi thi^u...^..... ...................................................................................................................................................................................... ......... 165
3.1

Lirft vuc ung dyng cua h£ thong may tinh.......................... .....................................................................................................166

3.1.1

Tong quan ve kinh doanh di|n tir (e-business)........................................................ .................................... 166

3.12

Tong quan ve e-learning...................................................................................................................................... 168

3.13

Tong quan ve chinh phu dien tir (e-goventment)........................................................................................ 173

3.2

An ninh................................................................................................................................................................................................... 178

3.2.1

An ninh Internet........................ ............................................................................................................................. 178

Tra ldi lai tap................................................................................................................................................................................................. 187
4.1

Tr4i£N cho Quyen 2 Chuong 1 (Phat trien phan mem)..........................................................................................................187

4.2

Tra ids cho Quyen 2 Chuong 2 (Bao tri va v£n hanh he thong).......................................................................................... 202

...


G!6i th?eu
n

Loat sach giao khoa nay da dupe xay dyng dya tren Chuan Ky nSng Ky sir Cong nghe thong tin dupe dira ra cong cpng
vao thang 7 nam 2000. Bon tap sau day bao quat toan bp noi dung cua tri thuc vk ky nang co ban can cho viec phat
trien, van hanh va bao tri h£ thong tin:
Qityen 1:

Gidi thifu ve he thong may tinh

Quyen 2:

Phat trien va v§n hanh he thong

Quyen 3:

Thiet ke trong va lap trinh —Tong lugrng tri thiic cot loi va thyc hanh

Quyen 4:

Cong nghe mang va co sd dir li£u

Cuon sach nay neu nhung giai thich de myt cadi c6 he thong, de nhung nguoi dang hoc ve phat trien, v?n hanh vtri he thong lan dau tien co the de dang thu dupe nhung tri thuc trong cac linh vyc nay. Cuon sach nay bao gom cac
chuong sau:
Chuong i :

Phat trien he thong

Chirong 2: V?n hanh vh b io tri he thong


1 Phat trien he thong

M mc dich cua chuong
Voi cac cong ty, dieu thiet yeu la thu duoc ioi nhu£n. Tuy nhien, voi tinh hinh kinh te hon lo$n hifn nay, rat kho du
doan xu hudng tuong lai. Trong tinh hinh nhu vay, cac he thong xu ly thong tin trd thanh quan trpng song con cho hoat
ddng nghiep vu, va do do la mau chot cho su ton tai cua cong ty. Cac ky su xir ly thdngtin, tat di cac he thong thiet ke
va phat trien xir ly thdng tin, da ngay cang trd nen quan trpng.
Chuong nay ndi ve luong phat trien sir dyng md hinh thac do, cung cap mpt co sd cho vifc phat trien h f thong, cac mdi
trudng phat trien, cac hf thong quan ly, va vifc sir dyng cac goi phan mem. Ve chi tiet, bao gom cac m yc sau:
•

D$i cuong ve cac phuong phap iu$n phat trien hf thong, va cac tien trinh phat trien su dyng mo hmh thac do.

•

Cach lap bieu do phan tich yeu cau, va cac cdng nghf thiet ke khac nhau.

•

Cac ngon ngu l$p trinh va ky thu^t lap trinh.

•

l am quan trpng cua kiem thir, va cac phuong phap thiet ke cac trudng hpp kiem thu.

•

Cac cong cy dupe dung trong mdi trudng phdt trien, v^ cac ky thuat va hf thong cho vifc quan ly phit

•

Cac kieu goi phan mem va cach sir dyng chung.

trien.


Giai thicu
Nam muoi nam da troi qua ke tiV kin to may co ten la "may Imh" xuat hien Ban dau. khong co ly thuyet bay phuong
phap lu$n nao cho viec phat trien he thong, tno nen Vi^c phai trien tuy thupc chu yeu vao "tai nghe" cu«i ky su. Dieu
nay hoan toan tuong tu nhu nguoi thy mpc xira kia lain nha theo "true giac" va "kinh nghiem" cua hp. Tuy nhien, cac
he thong da dan tro nen ngay mpt Ion hon, su mo rpng va viec thay doi cac he thong hien co da tro thanh can thiet,
song song voi viec phat trien cac he thong moi. Them vao do, nSng suat phat trien da tro nen cao hon. Tinh huong nay
da dat toi cho ma chi dung "tai nghe" thoi la hoan toan khong du, dan toi viec mac nhien phai co cac ly thuyet phat
trien he thong, va cac phuong phap kv nghe de thuc hien cac ly thuyet do.

Ngoai nhung phuong phap quy uoc, nhung phuong phap va ly thuyet phat trien inoi dupe dua ra da cho phep d^t
dupe n&ng suat cao hon, va ciing than thien hon voi nguoi dung.
Chuong nay de e£p den cac ly thuyet co so cho viec phat trien he thong, va cac phuong phap lu£n cua chung. Viec su
dung co hieu qua cac goi phan mem moi va cac phuong phap kiem diem cot yeu cua cong viec phat trien he thong
cung dupe trinh bay trong chuong nky.


8

1.1

Phuong phap luan Phat trien he thong

Ngoai cac phuong phap iugn phat trien he thong, myc nay rung giai thinghiep, cong nghe thong tin va cac phuong phap phat trien chinh.

1.1.2;

(1)

Vai trd cua to chvcc phat trien he thong

Hoat tf§ng xi nghi$p va h$ thdng tin

De tao ra su phat trien lien tyc cua xi nghifp can rat nhieu no iuc, trong do vi?c su dyng Cong nghe Thong tin (CNTT)
co tam quan trong song con.
Voi cac xi nghiep, co hai kieu thong tin:
•

Thong tin n$i bp* Thong tin sinh ra qua cac hoat dpng nghi£p vu, bao gom c i c a c hoa don, hieu mau va tai lieu

quin ly duoc dung trong ban hang, d$t hang va ke toan.

•

Thdng tin ngoai: Thong tin phat sinh ra tuy thuQC vao tinh trang kinh te xung quanh cong ty, ke ca vi§c b in san
pham, xu hirdmg cac nganh cong nghiep c6 lien quan, dong thai cua cac cong ty c^nh tranh, va cac giao djch voi
cac cong ty lien quan.

Doanh nghi£p se su dyng die thdng tin tren trong ho$t dQng h in g ngay cua minh mgt cach hi£u qua, v6i he thong
thong tin lam phuong ti§n. H§ thong thong tin ducrc pHSn thinh hai I091:
•

H f thong xur ty tic nghi^p: Duqc dung de ho tro cho die hoat dong hing ngay v i cung cap du lifu quan ly
doanh nghiep. H£ thdng nay thi/c hien vi§c xir ly thdng tin deu ky nhim ting nin g suat v i dii tidh hieu qua
v|n hanh doanh nghi^p.

•

thdng tin chien \\tQc: De d$t dupe cac myc dich da dang, dieu quan trong li su dyng dupe lai nguyen sin
co, con nguoi, v&t tu va tien bac, theo cach hieu qua nhat. He thong nay cung cap thdng tin can cho vi£c quin iy
cac tai nguyen noi tren. H§ thong nay chu yeu duoc dung de tao ra cac bao cao tir g6c dd quin ly.

Hinh 1.1.1 H f thong tin chien htgc va h f xti ty tac nghify

L£m k£ ho^ch chi6n luge
Ph§n tich thj tru’dmg

<He thong tin chien lirpc>

Phan tich ban h&ng

Quan If ngan sach vci chi phi

c
'Cfl

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Muc dich cua tung he thong bao gom:

iz:
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Ara
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CD

b- C

b
«
b
£
n
c
£

<H$ xi> li tac nghi£p>


<He thdng xu iy tic nghiep>
•

Lam giam nhan cong cho nhurtg thao tac 06 ii.en quan

•

Lam giam vi^c xu iy nghiep vu

»

Larn giam thai gian giao hang

•

Lam giam viec quan ly kho

•

Thyc hi?n cac thao tac khong giay td

<H£ thong tin chien luy»c>
•

Lam tang doanh so ban hang

•

Cai thifn hieu qua ban hang

•

Cai thien sir thoa man cua khach hang

•

Tao ra thj tru-ong moi

* Noi chung, mQt to chuc chju trach nhiem phat trien c(ho$c gpi bang ten khac tuong ty nhu vay), cac ky su* he thong (SE)va cac laptrinh vien thupcve to chuc nay. Mgt to
chuc su dyng cac he thong duoc phat trien dupe gQi la to chuc ngudi dung.

(2)
(D

Tien b$ trong CNTT vh To chuTc Phat trien H£ thong
Tien bQ trong cdng ngh$ thdng tin

Nhung budc tien mdi day trong cong nghe & ra't dang ngac nhien va da dang. Trong so do, nhung tien bQ sau dSy duyc

xem la cac nhan to anh hudng ro ret tdi viec ph3t trien he thong.
4
a.

Tien bQ trong cong nghe may tinh

g

Su cai thien hieu nSng dia ca may tinh ca nhan vh tram lam viec, va viec giam gia dang ke cua chung la mdt dieu dang
kinh ng$c. Nhfrng thao tac ma co thdi chi thyc hien diryc vdi may tinh Idn thi bay gid da co the duyc thyc hien b3ng
nhung may tinh nhd hon.
b.

Su dyng ryng rai cic g6i phan mem

Do sy phat trien nhanh chong cua cac goi phan mem, nen nhung goi phan mem Quan trj Co sd Du lieu Quan he
(RDBMS : Relational Data Base Management System) va bAng tinh nay da sin co, va vi$c tfch hop chung vao mQt so'he
thong cung trd nen kha thi.
c.

Tien by trong cong nghe mang

Doi mdi cdng nghe trong linh vyc thong tin va truyen thong, bao gom sy ket hop Mang Cyc by (LAN - Local Area
Network) va Mang Dien rpng (WAN - Wide Area Network), va viec xay dyng cac mang nyi bQ (intranet) va mang
ngoai bQ (extranet mang duQc tao ra hang each md rQng mang noi by ra ben ngoai cong ty), la rat dang chu y .
d.

Tien by trong cong nghe *i*y dung

he thong

Cong nghe da djch chuyen tir cach tiep can hudng quy trinh sang cach tiep can hudng du lieu (DOA - data oriented
approach). Ket qua la cac ky phap duyc tao ra de bieu dien cho cac thiet ke cd cau true nhu Bieu do Luong Du liei>
(DFD - Data Flow Diagram), Bieu do Thyc the - Quan he (ERD - Entity-Relationship Diagram), Cap bac CQng vdi Va;
Xu ly Ra (HIPO - 1lierarchy plus Input I’rocess Output), da duoc chap nhan ryng rai. Them vao do, cac cong cy Kv
nghe Phan mem.voi Sy try giup cua May tinh (CASE - Computer Aided Software'Engineering) da xuat hien de ho try
cho nhung no lye phat irlen h'} ‘hong, vk da dtrye sir dyng **$ng rai


10

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Vdi viec tang quy me hf thong va dura multimedia vao lie thong, cac to chirc phat trien hi? thong dang phai Strong dau
vdi nhung van dc sau:
a.

Tang khoi luong cong vifc ton dong

So iupng cdng viec ton dpng cua mot to chuc phat trien he thdng da tang len, con so nay cho thay viec phat trien he
thong khdng the b5t dau ngay Jap tire theo yeu cau cua ngudi dung. Trung binh, moi cdng ty deu ton dQng 2 den 3 nam
cdng vi§c.
b.

S y xuat hifn he thong mutimedia va tang so lugmg cac he thong quy mo ldn

Cac he thdng multimedia trong dd sir dyngh cac du lieu da dang nhu am thanh, video va van ban, da di vao thyc te.
Them vao do, WAN va LAN da dupe ket hpp vdi nhau v'& nhieu mang ngi bo (intranet) da dupe xay dyng. Vi v$y, Vgay
nay ngudi ta phki giii quyet cac he thong cd quy md ngay cang ldn va phuc tap.
c.

Tang cong viec bao tri

Vdi auy md cua cac he thong ngav cang md rong, khoi luong cdng viec bao tri cung tang len. Khoi luong nay tang len
bdi vi cac yeu cau sua doi he thong tu ngudi dung tang len, viec sua doi cac he thong hien co trd thanh can thiet, va
viec sua doi toan bp he thong do gap nhieu ldi cung tang len.

(D

Vai trd mat cua to chirc phat trien h i thong

Ben canh nhung cong viec quy udc ve viec phat trien he thong va bao tri, cac to chuc phat trien he thong hien nay dupe
trong dpi thyc hien nhung cdng viec cd lien quan nhu sau:
a.

Ph£t trien he thong cung vdi van hanh vabao tri he

thong

Ben canh cac cdng viec quy udc, cac to chu*c phat trien he thong phai chap rihari cdng nghe va phuong phap mdi mpt
ckch tich eye.
b.

Xay dyng vk van h ' nh cac co sd dir lieu va mang

Cac ca sd dir lieu khac nhau la yeu to can thiet ddi vdi viec van hanh va quan ly nghiep vy. Ben-canh dd, bay gid khong
the xem x£t cac hoat dpng nghiep vy ma khong dung mang. Viec xay dyng, van hanh vk quan ly ckc co sd dir lieu va
mang nay dupe coi nhu cong vifc thiet yeu cua td chuc ph&t trien he thong.
c.

Lap ke hoach va dieu phoi tin hpc hoa toan cdng ty

Viec lap ke hoach cho cac he thong ldn bao quat toan bp cdng ty, va phan anh cai nhin cua ngudi dung va ban dieu
hanh cong ty, rung la mpt cdng vifc quan trpng cua td chuc.
d.

Gan chat vdi ngudi dung

NgUdi ta trong dpi rang to chuc phat trien he thong chap nhan cae yeu cau cua ngudi dung mpt cach tich eye va phat
trien cac he thdng cd tinh thyc tien hon bao gid het. To chuc phat trien he thong cung can san sang cung cap ho tip ky
thuat can thiet de hudng dan mdi trudng tinh toan ngudi dung cuoi (EUC), huan luyfn tu xa va huan luyfn tai cho ve
xu ly thong tin trong cdng ty.

1.1.2

Mo hinh phat trien phan mem

Vdi vifc phat trien hf thong, ngudi ta dung nhieu md hinh khac nhau tuy theo quy md cua cong ty va each thuc lain

vifc chu dao trong cdng ty. (!) day, nhung phuong phap nay dupe md ta mot each van tat. Dac biet, chung toi se neu chi
liet ve md hinh thac do Uong myc 1.1.3.


X err. x e t csisch xiiy n i’3 m ini* ho& tro n g H inh 1.1.3

>?ro c h o c h iV ’g te d e hie*? h o n v e c-*r h th'.Vc H fe ?fi.Ap, cii# vt£c

vy!*-'

d i.m g h e thong.

7.12 Q,«y triah xay dung nhd

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> -* vl- -ããããã- --- r>----dyng. Dtra tren cac yeu cau nay, nguoi xay dung dua ra gia

thanh uoc lugng, cac ban ve so do va lich bieu, va noi dieu

xay

dung nha

do voi khach hang. Them vao do, nguoi chii nha con phai di
xin phep cac co quan chinh phu co lien quan.
Dya tren thiet ke so do, ngirtVi xay dung tao ra cac ban thiet
ke chi tiefc co tinh toi nhung rang bu§c can thiet nhu cac dieu
kien dja iy va xa hoi cua vj tri nay va gia thanh. Cuoi cung,
viec thiet ke dupe chia xuong muc cho phep viec xay dyng
thyc.

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Viec lap rap dugrc thg n\Qc thyc hien tren cac thiet ke.
Vi§c kiem tra dugc tien hanh moi khi hoan tat mQt bQ ph$n.
Den cuoi, vice kiem tra dugc thyc hien vai sy co mat cua
kh£ch h&ng. Sau do ngoi nha dugc chuyen giao cho khach
hang.
Nhieu lo$i bao tri se dirge tien hanh tuong ung theo yeu cau
cua khach..

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flo a r^ t

S M T
Neu chi rieng b&n ve, khAch hang kh6 co the hinh dung ro rang ve ngoi nha va trong no se ra sao khi dirge hoan tat. Do
d6, ngudi ta kiem tra voi mo hinh ngoi nh&, ho£c voi cac anh 3 chieu tren may tinh
CAch giai quyet tuorng tu cung dugc dung trong phat trien he thong.

(1 )

Md hinh thac do

Mo hinh th^c do, mQt cong nghe ph&t trien he thong, van la mo hinh dugc sir dung rgng rai nhat. Trong mo htph nay
cong vi^c dugc phan chia thanh mgt so giai doan, va viec quan ly dugc tien hanh cho timg giai doan.


*2

$Kf&h 1.1.3 h£o hj’tih thdc ifp

Cai ten "thac do" noi len rSng, cong viec dien ra trong mo hinh nay tir thupng luu (lap ke hoach co so) xuong ha luu
(kiem thu), khong bao gid di ngupc lai.

(2)

Mo hinh ban mau

Mo hinh th^c do co nhung han che sau day:
- Vdi mo hinh thac do, eye ky kho hieu ro yeu cau cua nguoi dung trong giai doan lap ke ho^ch co sd cho he thong. Doi

khi ngay ca khach hang cung khong bie't duoc nhung yeu cau do.
- Cac bieu dd thiet ke va gi&i thich bang mieng doi khi khong du.
De gi&i quyet nhung h$;i che nay, nguoi ta de xuat ra mo hinh ban mau. Vdi mo hinh ban mau, he thong dude xay
dyng se dupe lam mo hinh tho vdi cac ngon ngu lap trinh don gian nhu Ngon ngu Truy van cd Cau true (SQL Structured Query Language) de giup cho khach hang hieu. Sau do, cong viec phat trien he thdng se b3t dau.
BAn mau bao gom nhieu mo hinh da dang.
<Phan 16p theo phuong phip xay dyng>
•

"Kieu vut di": Cac manh mau thu bi vut di sau khi da dat tdi myc dich cua chung.

•

"Kieu khung xuong"': Cac chi tiet dupe them dan vao cac manh mau thu de md rpng dan no thanh h£ thong du
dinh.

<Phan ldp theo muc dp bao quat>
•

"Kieu dung bp phan": Mo hinh nay duoc dung trong cac giai doan xac djnh yeu cau va thiet ke ngoai.

•

"Kieu dung toan bp": Mo hinh nay dupe xay dung cho tat ca cac giai doan.

Hinh 1.1.4 cho thay mpt vi dy luu do cua mo hinh ban mau theo kieu dung bp phan.


Ngu’cyi dung cho
chay ban m iu

O&nh gia
,

Thiet ke trong

|—
I OK

r j

L__

Thiet ke ch. trinh
L$p trinh

IZ Z 3IZ
Kiem tniK
J

| V$n hanh v& bao tri J

Vifc dung mo hinh ban mau dem toi cam giac cho nguoi dung cam giac ve sy tham gia cua minh vao cong vifc phat
trien hf thong, ngan ngua cac loi trong cac giai do$n thuyng liru von anh huong dang ke tdi cong vifc ve sau.
Tuy nhien, mo hinh ban mau bao gom cac van de sau can duyc giai quyet.
*

Chi phi phat trien vuvt qua mo hinh thac do.

•

Kho dieu chinh ljch bieu thyc hifn.

(3)

Mo hinh xoan dc

Trong mo hinh xoan 6c, m§t loat cac tien trinh bao gom thiet ke, lap trinh va kiem thu diryc l$p di lap lai cho tung don
vj co e cua hf thong; vifc phat trien lap lai va nhan len nhieu lan (xem Hinh 1.1.5).
<Cacd$c trtmg>
•

CAch dung mo hinh nhy thich hyp cho nhung trudng hyp ma cac dun vj con cua hf thong tuong do! dpc lap
lan nhau.

•

Phan nao tuan theo mo hinh thac do.

t

Cho phep sir dyng mo hinh ban mau neu can.

•

D uqc sir d y n g trong kieu phat trien huong doi tuong va cac kieu khac.


14

(4 )

Phat trien huting do! turgng

Gan day, ngudi ta chu y den cach ph£t trien huong doi tupng. rrheo me hinh nay, h f thong dupe xet nhu* mpt tap hpp
cac doi tupng, va vifc phit trien dupe tien hanh tren co s6 doi tupng. Trong ph£t trien doi tupng, quy trinh tir phan tich
den thiet ke den thyc hifn dupe tien hanh l|p di lap lai, tao nen mpt loai mo hinh xoSn oc.

(5)

Cau true Phan tach Cong viec

B £ dat toi myc dich cua minh, mot dy an phat trien hf thong dupe phan taeh thanh cac m uc theo thu ty sau, tuy theo
tien trinh phat trien.
1.

Muc quyet djnh cau true chinh cua dy an

2.

Muc cong vifc tao nen khuon kho cho tung giai doan

3.

Muc cong vie- hifn hanh chi tiet

Tu ket qua phan t&ch cac muc, nguoi ta bo sung them die myc dich cu the, ljch cong vifc, va vifc quan ly cieh tr'mh (cac
chi tiet cua muc dupe x&c djnh b6i vifc quan ly n&y cang mjn cang tot), de thu dupe Cau true Phan tach C6ng vifc
(WBS - Work Breakdown Structure). WBS dupe bieu dien bing cau true phan cap nhu dupe ve trong H inhl.l .6.

H in h 7 7 /.

u u an phcii tr»in san j

Vi|c dung WBS cd nhung ich loi sau:
•

Co dupe iroe lupng chi phi va du lieu cho viec phan tich chi phi.

•

Lam sang to cau true cong viec va bao qua! cong viec cua mpt dy an, cung vdi tr^ch nhiem ve cong viec.

ã

Nam dupe tien dp hien tô*i cho tung don vj cong viec, va l|p ke ho^ch cong viec dupe de dang hem.

•

Ten cua cac don vj cong viec da phan taeh va ten cua he thong phan lop la mpt phan cua bi quyet chuyen gia.

Voi WBS, myc dich cua cong viec, nhu chat lupng, chi phi va thoi gian, dupe cho tren co sd don vj cong viec. Cho nen,
die n.yc tieu dong vai trd tham chieu cho cong viec dupe thuc hien.

(6)

Tien trinh va Mo hinh Tien trinh

Tien Tinh dupe djnh nghia 1& t|p hpp c£c don vj cong viec (vi dy nhu phan tich, thiet ke v& che t$o) can thiet trong viec
I90 n s&n pham (ke c& sin pham phan mem), dupe sip xep theo chuoi thoi gian. Moi cau phan cua tien trinh dupe gpi

la "gai do$n tien trinh". Vdi WBS mo ta d tren, cong viec dupe bieu dien theo cap b$c, nhung khong theo chuoi thdi
gian.Su khiic biet ldn la d day.
Tien rinh dupe thiet ke so bp trong giai doan l|p ke hoach co sd. Trong ban thiet ke nay, mo hinh tien trinh dupe neu
tron^Hmh 1.1.7 cd the dupe dung de tham khao.
Hinh .1.7 Md hinh tien trinh

giai

L$p

doan

ii^n

hoach


linh

7hi6t k£ quan ni£m

ti^n

rinh

k&

X£c djnh

Thi^t k6

Ch6 tao. x&y dt/ng v& ki&m thu-

yeu cAu

Chuyen

V£n h^nh

dich

v£ boio tri

Chuyen

Bao tri

trinh>

1>

Thi£t k£ ca sa

7hi6t

MS hoa

Kiern Ihu1

chi
ti6l

djch

________

.......... .


16
............ 1 ........... ....... ........ ..........
KA hoach
hoA
tiAn trinh

ih6n#

--------- 1
Sinh
ThiAt
trinh
k£

- •-

........i
i

B3C iri
|

ChuyAn

chirong : KiAmthu'

djch

chu'ortg
trinh

-

t»An
3>

hinh
trmh

L?p kft hc^cti

KA tioach
h$ thAng
hmh tien

ThiAt kA

Xac djnh
y6u cAu

ThiAt kA
ngudi

hoa

ThiAt

hinh tien

Thi/c hi§n phat triAn

kA

ChuyAn
djch sang
v$n hinh
there tA

Bao tri

KiAm thi>
h$ thAng

Bio tri

trcng

ThiAt
kA
module

trinh 4>

L£p kA
hoach h£
thAng hod

KiAm tm> h$
ihAng

ChA tao

PhSn tich
hfcthAng

ThiAt kA
h£ thAng
d?i

M3
hoci

ThiAt kA h$ thAng
chi tiAt

ChA tao

TtiiAt
kA cAu
true he
thAng

Up
trinh

KiArr.
thtp
den vj

KiAm thu* m6c
iiAi

1

ChuyAn
dich

KiAmthu*, chuyAn dich

V$n hinh
va b3o tri

.

cu*ong

trinh 5>

hinh tien
trinh 6>

L$p kA
hoach h£
thAng

I

PhSn tich
h$ thAng

TtwAt kA
giao di£n
ngu’iri
dunp

ThiAt
kA cAu
true
chuong
trinh

KiAm
thir
chuang
trinh

KiAm
thu*
m6g
nAi

KiAmj KiAm thi>
thiV
v$n h£nh
h$
thAng

BAo tri/
danh gia
h$ thing

Cac san pham phan mem dupe tao ra qua tung tien trinh phat trien. Do do, bin thiet ke cua tung tien trinh, tu do tao
nen co so cua tien trmh, se co anh huong Ion toi chat lupng va chi phi cua sin pham phan mem.

1.1.3 Vong ddi phun mem
Vong d6i la tien trinh tu khi sinh den khi diet, hay khoang song cua mpt vat song hoac mpt san pham. Vai khai niem
ve v6ng ddi phan mem (SLC) cung vay, khoang thai gian tu thai diem b3t dau d y an phat trien h$ thong cho den th6 i
diem vi£c cap nhat he thong ket thuc dupe xem nhu cupc doi cua he thong. Vay, cac hoat dpng dien ra trong thai ky do
(dirp»c bieu dien theo kieu cupc song thtfc) dupe dung lam mo hinh dien tA cho moi quan h£ giua cac tien trinh.
Hinh 1.1.8 Vong ddi cua h f thong phan mem

Chuyen sa n g
rncyi

Vong doi cua he phan mem
Trong phan sau day se giai thfch ve mo hinh thac do, la mo hinh dien hinh nhat.

(1 )

O ac truYsg ciia mo hinh th a c do

Hinh 1.1.9 bieu dien mpt hinh anh toan the cua mo hinh thac do.


17

Hinh 1.1$ Binh anh toan the cua mo hinh thac itu&c (cau true hinh. chu V)

f

L$p ke hoach cu1so R

j

______ ______________
j Phan tich

___ JR

]

j

__ \ ___ ___________

_

j

Van h6nh/bao tri

[

Kiem ihfr v$?; hanh

Trong mo hinh thac do, cac ky thuat dircri day dugc sir dyng. Vi v§y, co the true qaan hoa mo hinh nay theo cau true
hinh chu* V trong Hinh 1.1.9.
ã

Tir giai doan lĐp ke hoach co s6 tai giai doan l$p trinh: phuorng phap l£m xnjn timg buoc (tiep can tren
xutfng).

•

Tir giai doan kiem thu don vj toi giai doan kiem thu vgn hanh: phuong phap tich hgp timg bixac (cach ciep
c$n dirori len).

Cac d$c trung cua Mo hinh thac do dupe tom tat sau day:
<Cac d£c trung>
•

Cong vi§c ph&t trien h£ thong dugc chia thanh mot so giai do$n de quan ly.

•

Khi cong vifc cua mpt giai doan ho&n tat thi san pham cua cong vi£c (ke ca cac !o$i thi li£u thiet ke) cua giai
doan nay dirge xet duy£t de kiem tra tinh dung din.

•

Cac san pham cong vi§c (ke ca du lo^i tai li£u thiet ke) tir giai do?n n&y dugc chuyen tiep sang tien irinh ti£p
theo, trong tien trinh do cong vi«?e dugc thyc hien v6i sAn pham vua nh|n dugc. Theo cach nay, s\jt nhat quan
trong vi£c phat tiien h| thong dugc duy tri.

•

Ve co b&n, khong dugc phep tro l$i cong viec cua giai doan trudc.

•

Cach to chuc dy an co tam quan trpng chu chot

Nhu da mo t£ 6 tren, vi£c phan chia tien trinh phat trien he thong th&nh mpt so giai doan de quin ly la mgt lrong
nhung die trung cua md hinh thac do. Hinh 1.1.10 minh ho? moi quan h§ giua tung giai do?n vh khoi lupng cong vi£c
6d6.

Trong cac myc (2) toi (8) duoi day, se mo ta dai cuong timg giai doan cong viec trong phat trien h£ thong.


iS
Hinh 1.1.10 M oi yuan h$ xtica Ittrig giai itoau trong md hinh thdc (to va k h o i hrpng cdng vi$c cua no

(2 )

Lap ke hoach cd sd

L4p ke hoach co s6 la buoc dau tien cua viec phat trien he thong. Can ph&i co hieu biet thau dao ve cac hoat d§ng tin

hoc hoa dang co, neu khong, se khong the n&o phat trien dupe he thong co the thoi inan cho ngudi dung. Do v$y, l$p
k§'ho$ch co sd b it dau bSng viec phan tfch he thong dang c6, roi x ic djnh ro van de cua n6.
Hinh 1.1 J 1 L$p kehoQ ch c o $ d

Thu tyc chi tiet trong lap ke hoach co s6 du
Ke hoach h? thong hod

(D

Lap ke hoach he thong hoa la cong viec soan thao ra cac ke hoach co so cho mpt he thong.
<Nhiem vy>
•

Dieu tra va phan tich cac van de trong cac hoat dong co muc dich he thong hoa.

•Dua tren ket qua ciia muc a, khao sat giai phap tot nhat va xem xet iai sir can thiet nhat trien he thong. Neu sau
khi khao sat va xem xet, U»i thay rSng co mot giai phap tot horn, thi chap nhan giai phap tot han.
Neu tu cong viec cua muc b thay rang vi^c phat trien he thong
hoa va de tnnh cho nguoi to trach nhu/iu.

jvioj

la thich hyp, thi !$p han ke ho^ch he thon^


iQ

«

Bar ke hogch h£ thdng hoa.

2D

K e h o u c H thirc h i$ n ii\ a h i

Sau khi ngudi cd trach nhi$m chap thuan ke hoach h£ thdng hoa, thi ban ke hoach thyc hi£n (ban ke ho^ch thyc hi£n dy
an) dupyc lap.
<Thu tyc>
•

Dy- an dupe to chuc (ke ca bd nhi^rn ngudi phy trach)

*

Ban ke hoach tai nguyen he thdng (udc lupng) dupe soan thao.
o

Ke ho^ch nhan sy

o

Phan cung cho phat trien h£ thong

o

U ac 1irj!t.c quy rod phat trien (ke ra nhan luc va ngan sach)

o

Tai chinh

Va nhung thu khac
•

Ban ke hoach tien trinh cong vi£c va ljch bieu muc cao nhat dupe soan ra.
Cocac kieu lich sau:
o

Ljch bieu muc cao nhat

: Ljch cho toan bp h£ thong

o

l,jch bieu mire trung

: Ljch cho tung giai do$n trong vi£c phat trien h£ thong.

o

Ljch bieu mire thap nhat

; Ljch bieu cho tung ngudi cd lien quan.

Neu lap dupe tat ca cac loai ljch bieu tren tai giai doan nay \k tot nhat nhung thuc te thi kho lam dupe. Cho
nen it nhat can soan ra ljch bieu muc cao nhat tai giai doan nay.
•

Bin k6‘ hoach phit trien.

Trong xac dnh yeu cau, cac chuc nang can dat dirpc tieu tao nen dau vao cho vifc phat trien h£ thong, va cong vi£c
phan tich vi djnh nghia cac yeu cau doi vdi he thong thdng tin dupe lam chi tiet hon so vdi cac ban ke hoach phat trien,
bang cac pluong phap cd cau true nhu DFD (Bieu do Luong Du li£u) va ERD (Bieu do Thyc the Quan hĐ)
ã

Thu thap thong tin ve hĐ thong, vi dy nhu cong vi£c trong cac chuc nang can dat dupe (mo hinh cong vi£c
dup: sinh ra tai day dupe gpi ia md hinh logic hifn tai), cac bieu mau dirpc dimg va cac myc tieu.
Xac Jjnh cac yeu cau ve h£ thong vdi tu cach la mpt long the, bao gdm cac chuc nang, cac yeu cau hieu nang va
that tac.

e

l.iin sang to cac yeu cau cho ca phan cung va phan mem
'■»


20

•

Ban d£c ta yeu cau

Tam tat vi'vi$c Jap ke hoach cu t;a

(§)

Vi£c lap kehcach ca sd la giai doan thiet Ice ra dai cuang ve h $ thong tin, ke ca vi|c phsir. tfch h§ thong can phat trien va
vach ta ijch bieu muc cao nhat. Ket qua cua no anh huong rat nhieu tdi cac tien trinh sau dd. Ngoai ra, day la giai doan
dau tien trong vi£c phat trien he thong. Do do, dieu can thiet la cong viec phai dupe thyc hien vdi sy xac nh$n cua
ngudi dimg, cong v iecd u p c ngudi phan tich h§ thong co ky n&ng cao va cd tri thuc cot loi thyc hifn.

(3)

Thiet ke ngoai

Thiet ke ngoai la thiet ke cho phan thay dupe ben ngoai, hay nhung phan danh cho giao tiep vdi ngudi dung. Do do, he
thong dupe thiet ke thuan tuy theo quan diem cua ngudi dung
khong de y tdi nhung rang bu$c ve phan cung (nhu
may tinh). Ben c?nh do, cung phai lam sang td cau tnjc h£ thong can cd de dat tdi duoc thiet ke do.
Hinh 1.1.12 Thiet k e n g o a i

<Nhiem vy>
•

Kiem tra d$c tA yeu cau

Sau khi kiem tra ban dac ta yeu cau co trong bAn ke hoach co sd, thi vi£c xet tong quan ve he thong dupe bieu dien
bdi vi?c dung cac bieu do sao cho viec xir ly va luong du lieu cd the duoc hieu de dang. Dya tren cac bieu dien nay,
thyc hi|n viec phan chia h? thong thanh cac he con va thiet ke vao/ra. Cac DFD hay HIPO dupe dung de ve bieu do,
•

Xac djnh cac he con va phan d u a tiep

Toan bp he thong duoc chia thanh mpt so he con tien co sd chuc nang, roi he con lai dupe phan chia tiep thanh cac
don vi nhd hem.

•

Thiet ke tai lieu va man hinh.

Trong thiet ke man hinh va tai lieu, cac thie't ke phae thao cho man hinh va viec chuyen doi man hinh, thiet kephac
thao cho tai lieu vao/ra se dupe tao ra. (Cac cong viec chi tiet de thyc hien thiet ke nay se dupe tien hanh khi lam
thiet ke trong.)
•

Thiet ke ma


( j dciy, vi^c chic't
•

ina, rinv" vIqc

dmh He thong ma,

ss

dupe tien hanh

Thiel ko dir Is6u logic

Trong thiet ke du lieu logic, mol quan lie giua du lieu duoc phan tich, va rut ra ung cu vien cho cu so dir liyu va *vi>.
(C ar r:6og \'»p* chi iiel: de thuc hifn duyc tien hanh khi iarn tiiiet ke trong).
•

Xet duyet thiet ke ngoai

Tai li£u thiet ke ngoai dupe xet duyet.
<T&i lipu>
ã

Tai iiÊu thiet ke ngoai

đ

Bao cao xÊt.duyĐt tai liÊu thiet ke ngoai

(4)

Thiet ke trong

Giai doar. thiet ke rrong danh cho phan khong thay dupe ciia h£ thong, va lam vi£c voi rihung thiei ke dupe xein xet tir
phia m£y tinh hay phia phat trien he thong. Trong thiet ke ngoai, hf thong dupe nhin tu quan diem ciia ngudi dung.
•Tuy nhien trong thiet ke trong, cac chi tiet dupe thiet ke b in g viec xem x£t tdi cac thiet ke ngoai nay dupe cai dat hieu
qua the nao tren may tinh, hay boi vifc tinh toi nhung rang bupc phan cung cung nhu phan mem.
Trong thiet ke trong, cac cong vifc minh ho? trong Hinh 1.1.13 se dupe thyc hifn.
Hinh 1.1.13 Thiet ke trong

<Nhifm vy>
•

Phan hoach va cau true chuc n&ng (thiet ke cau true)

Trong phan hoach va cau true chuc nang (thiet ke cau true), rndi h f con deu phan hoach thanh cac don
va luong du lifu va xu ly giua cac chuong trinh dupe lam sang to.
«

vilaptrinh,

Thiet ke du lifu vat H

Trong thiet ke dir lieu vat ly (thiet ke tep), de dung hieu qua cac dac irirn^ phan cung, vifc thiet ke v$t
co so du* lifu dupe dya tren thiet ke’du lieu logic da duyc ihyc hien trung giai doan phan tich he thong.
Thiet ke vao-ra chi tiet

lyve tfp va


22

TVivrttr
•

Vp' v » o ra chi Her car chi Het ve m in hinh va tai lieu vao ra duoc iiiiet ke bang vifc dun& mau difc bift.

Xet d uy f 11h«et ke Iron#

Vifc xet duyft duoc tien hanh voi tai lifu thiet ke trong.
<Tai lif u>
«

Tai lifu thiet ke trong

•

Bao cao xet duyft thiet ke trong

(5 )

Thiet ke chuttng trinh

Trong giai doan thiet ke chuong trinh, cac cau true trong ciia lung chuong trinh se duyrc thiet ke. Moi chuong trinh da
xuat hien qua vifc phan chia 6 giai doan thiel ke trong lai duchuc nang duNgoai ra, trong giai doan nay cung chuan bi cac ke hoach cho vifc kiem thu chuong trinh (kiem thu tich hypi va thiet
iap cat tru in g hop fcien’i tim. Xem minh ho* ve cac cong vifc du^c tier, hin h trong I Tinh 1.1.1.
H inh 1.1.14 Thiet ke chuong trinh

<Nhifm vy>
•

Thiet ke c6 cau true cho chuong trinh (Phan hoach module)

Trong thiet ke co cau true, moi chuong trinh lai duoc phan hoach thanh cac don vi chuc nang duoc goi la module de
cho ph£p de ding bio tri, ec>n lu6ng du lifu vi xvr ly giua c ic chuong trinh thi ro ring, m^ch l^c. Ben canh d6, cac
chuc ning cua timg module v i giao difn giua cic module cung duyc x ic djnh.
o

T}iiet ke cac trudng hop kiem thu chuong trinh (kiem thu tich hop)

Chuan bj cac ke hoach cho kiem thu chuong trinh, va thiet ke cic truong hop kiem thu.
•

Xet duyft thiet kechirong trinh

Trong xet duyft thiet kechuong trinh, tien hanh xet duyft tai lifu thiet ke chuong trinh.

<Tai lifu>
ã

lai lifu thiet ke chuong trinh

ô

ij-io cao xet duyft ihiet ke chuong trinh


(6)

Lap trinh

Trong giai doan lap trinh, se thuc hi$n viec thiet kc cac cau true logic cua module da djnh nghla irong giai doan thiet ke
chi tiet, va viift ma chirOTig trinh cho cac module Ben canh do, cune chuan hi cac ke hosch cho kiem thu module (kiem
thi? don v j), va thiet I§p cac (ru'Oiig hyp kiem thir.
hinh 1.1:15 Lav trwh

Ki&m thu* (ton vi

<Nhi£m vy>
• Thiet ke module
Trong thiet ke module, cac cau true logic trong cua module (cac thu tyc xu ly chi tiet ben trong tong module)
duoc thiet ke bang viec dung cac ky thu$t co cau true khac nhau.
• L^p ke ho$ch kiem thir don v j;
Cac ke ho?ch kiem thir don vj duoc chuan bj. (T$o ra dir lieu kiem thirthich hop, xac djnh Ijch kiem thir.)
•

Ma hoa

Tung module duQcma hoa trong ngon ngu* lip trinh
•

Kiem thir don vj

Tien hanh kiem thir dun vj cho tirng module
<Tcti lj?u>
•

Tai lieu thiet ke module

•

Bao cao xet duy^t thiet ke module

ã

Keho^ch kiem thir dor\ vj

đ Danh sach chuong trinh goc
® Bao cao xet duy?t chi rong trinh goc
• Bao cao kiem thir dan vj

(7 )

Kiem thu*

L.dng dec kiem thir duoc tien hanh-de pirat hi^n 16i tiuitg hanlv vi 'va caii tiuc cua module, chucmg trinh hay he t)i

voi hr cavh lh mot tong the (xem rh rh 1 i.16). Neu ioi duvc tim :v thi car, lam phan hci, nc-u car., va chuyer. den


24

doar*
lao
trinh hav
eiai doan
thiet ke de sua chua. Sau d6, lai lien h&nh kiem thu de kiem tra lieu 16i da diroc sira hay
*
*i
^ v»
'
d iu a .
Hinh h i . 16 Cac b a i ki/m thu

<Nhi?m vu>
•

Kiem thu don vi (duoc tien hanh trong giai do$n lap trinh)

Trong kiem thu don vi, moi module deu duoc kiem tra xem li£u nd co dupe thyc hifn dung hay khong.
•

Kiem thu tich hop

Trong kiem thu* tich hpp, cac kiem thu dupe tien hanh cho tung chuong trinh d u p ctao ra b§ng v i l i e n ket cac
module. Viec v$n hanh cua chuong trinh v& giao di£n giua ckc module cung dupe kiem tra.
•

Kiem thu he thong

Irong kiem thu he thong, sy v§n hanh cua he thong vdi tu cach la mpt tong the dupe kiem tra toan bp theo quan
diem cua muc dich va hin&y.
•

Kiem thu v£n hknh

Trong kiem thu van hanh, c&c nh6m van h*mh tu phia ngudi dung tien hanh cac kiem thu trong dieu kien va moi
trudng gidng nhu trong v§n h&nh thuc te.
<T&i li£u>
Bao cao kiem thu dem vj
Bao cao kiem thu rich hpp
Bao cao kiem thu he thong
Bao cao kiem thu van harih

Van hanh va bao tri
He thdng da dupe dua vao boat dpng. Cat: hoat dpng bao tri dupe tien hanh khi phai: hien thay khiem khuyet (vi du:
kh6 dung) hoac loi, hoac khi thay khong the tranh khoi thay doi trong he thong. Irong mpt so trudng hpp, h£ thong can
phai dupe sua doi.