đồ án tốt nghiệp tìm hiểu về web caching và thiết kế và xây dựng hệ thống

Đồ án tốt nghiệp
Lời cảm ơn
 !
"#$%&'()*+(',-. /
00.&1 2345 $6*7&8/
.9!:$ ;<=!   3&28
/>&=   3&( ?.2@3
"A*7&8)$B<4)28+CDD
;'"E)-$FG/EH-EI=> >
JK2%&K-&'*
Đỗ Hải Nam - KHMT - K46
Trang 1
Đồ án tốt nghiệp
I.3.1 Internet Information Server làm việc như thế nào ? 4
I.4 Web Browser URL Request 4
I.5 Web Server Response 5
I.8 Sử dụng Internet Information Server như thế nào ? 6
CHƯƠNG III: NGÔN NGỮ ACTIVE SERVER PAGE (ASP) 26
III.1 Active Server Pages là gì? 26
III.2 Mô hình của Active Server Pages 26
III.2.1 Cách viết các file ASP Script 26
III.2.2 Cú pháp của ASP 27
III.4 Sử dụng các method 30
III.5.1 Request object 31
III.5.2 Response object 31
III.5.3 Session object 32
III.5.4 Application object 32
III.5.5. Server object 33
III.12 Sử dụng các Component của ASP 36
III.12.2 Database Access Component 37
III.13.2 Các sự kiện Application-start và Session-start 40

LLL*MN*N+I2(O 8P$"=Q$IIP$"************************************RS
III.13.4 Kết thúc một Session 41
III.13.5 Quản lý các Session 41
III.13.6 Quản lý Application 42
LLL*MN*TE@U8+ $****************************************************************RN
LV*M*MDW%&8=6/=0(&)*********************************RR
IV.3.1.1 Đăng nhập 46
IV.3.1.2 Thay đổi mật khẩu 47
LỜI NÓI ĐẦU
DX2&1(8).Y"Y"$Y$-)Z W-.
@ (&); E=1(=!I["A*
V!8Y$ I["A>:'2==616&:E'
E24 >6&:&-=6E*\3%&8
:U8I["A./24%&8=(/'2
Z@(]8)-E8)Z@Z4&28U8%&1*+?6&)
"#I-HW=6&<EA2&=*V(I["A
"9=AY$-8^$1 I]B.&<YYYEL$$
%&]8=%&]B^@-*VV(C8B2:_
=`])U8]YYY.W8 ([.(]P$8
8J3"A!=8< "AZV(C8*+3"A)
8Ia :EHI :U8E4E
)?=`b/])8U8@*D&):><I
:@>2 =16*+(]) 
:'81)6&E.ZU8IZE4E
B  Ic>*D31.d"HE)?8)@
Đỗ Hải Nam - KHMT - K46
Trang 2
Đồ án tốt nghiệp
:=!6&2(U8!8.IZ=;1E4E)?
=#`11 2e*+1<"9=A=8 3>:<(

-_E*f@:E<)&4&)I["A2g
&;Y$-8*hi&;Y$-+888<(&%&
=((G]3"AY$-*
+H=!=(3&=6Y$-+8.2&2W]
( )$B)"@Y$-I$_<-E/I.I
=J%&823=6E4EIZ._$E@
23]1=()"=-j@(]E)?*
\U8$Ia'-)4<2(=6L$$.3E
@U8@8Y$ ':&=6Y$-+8=I8&> ?2
=)"(]*
\<8F=!@"&?I8&k
Chương I : Tổng quan về Internet và Intranet
+)Ia8828(-=6L$$.=6Y$-=3
@8Y$-E@L$$
Chương II : Tìm hiều về Web Caching
+)Ia88J2(-U8Y$-+8*l 
:]&]]@"&)(Y$-=dY$-+8)+$
Chương III :Tìm hiều ngôn ngữ ASP (Active server Page)
D':&AOQmJ; 'VnI :)"(]
Chương IV : Phân tích và thiết kế hệ thống
\88J ?=63G.2(]IZ"J(&:>
::28(]*
Chương V : Cài đặt và thử nghiệm
\88<@I]'EU8(]*
CHƯƠNG I: TỔNG QUAN INTERNET - INTRANET
I.1 Internet là gì ?
L$$@E)?4&I["A@J&)6
&>@(](E%&]><]2$
=(U8@E!*
Y"Y"$Y$-oYYYp8@'"q"8 ='

2"J(&L$$*+"J(&)<2=!8&%&88
Y$-*+r$.8<]2=!8&%&8]2$
d'</) $2*
+8Y$->:38=G-.'. .8*+8)
>:<d@)?Z>!*h8]2!
L$$8>:&)&14&*
) $2$8)'<098,Y$->*n_
2=) $28>:)!@8 4U8@Y$-I$*
f@Y$-I$>@8UU8Y$-I$>=>@98,"&)1
Đỗ Hải Nam - KHMT - K46
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Đồ án tốt nghiệp
</srt$I&$8ostp*st9?U8
)?="#!@8Y$-9*
I.2 Intranet là gì ?
L8$"8=D+muLmC$v22]2!L$$,I[
"A&w&)6L$$=AU8>"H:&1 
!I["A@E*V?"A@)>:d@Y$-
I$=$,=U8)8WX3.
E***+=&)&1-_"HY$--vI$*
I.3 Internet Information Server là gì ?
L$$Lr8Q$=$oLLQp@Y$-I$=$ e 8-]
EL8$8)L$$*L$$Lr8Q$=$&)6
-_"H) $$D8Ir$moDDmp.L$$Lr8
Q$=$B>:"H 3xDmdl $*
I.3.1 Internet Information Server làm việc như thế nào ?
Y$-  @  ( ]  )&  4& ot$%&$Ip  =  3  ot$I I$p* Y$-
-vI$)&4&-_[@st!Y$-I$=$.Y$-I$=$
3E-_E@8DfY$--vI$*
Df>:@8Y$-i<&IcZY$-I$=$d>

:@8Y$-@I$=$E82 3)&4&U8I["A
d@8ZA>I$=$*
I.4 Web Browser URL Request
f8Y$-L8$dL$$>@st"&)1*Y$-
-vI$)&4&@8-_[@st!@Y$-I$=$*Y$-I$=$
I["Ast:9=:98Y$-$)&4&
U8nvI$*
+5  st@&=G-&4>km.8
C8$.="#om8p!)&4&*m&w&)6
"H:&)6kDm.xDm=l $*8C8$?
8C8$Q)I$oCQpU8)?38*m8"#!
)&4&)?*V?"Ak
m3 D8 \"#om8p
 kuu vvv*Ir* u-82rr$
 Ikuu 
oI$&$DDmp
vvv* 8)* u88u"$I*
Đỗ Hải Nam - KHMT - K46
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l $kuu  $*$$*$"& u$I$8u8I)u"$*
r kuu *-&$8&*= uI8Iu8 8%&8"8uI8I*
f@stB>:38Y$-I$=$4 [K!2
E@8."J(&st<0=&]"#*Y$-I$=$
["J(&)!@'8)@Q :[K=E2%&
@8v$-*V?"Ak
t$%&$ID) $ st
Q8Df 8$  kuuvvv*Ir*u-82rr$u"$r8&*
LQOmL8 8  kuuvvv*I*u&Iu 8$M*"y+sQDz
L$$88-8I$+$  kuuvvv*Ir*ur$$"-82u &*"

+l8$v8)L$r8$
o+lLpI 
 kuuvvv* 8)*u8&8u8""* y{*{
I.5 Web Server Response
Y$-I$=$ 3)&4&U8Y$--vI$-_E@8
Df*D8E>:8Dfi.8Df@d8
"8IA*
I.6 Trang HTML tĩnh (Static Page)
f@8Dfi8<&w-9Ic)&4&1
9=<dIcY$-I$=$*CI["A)&4&@8Dfi
-_| std+2=) $2U8st>.st
<[!I$=$*Q$=$ 3-_E8Dfi*
I.7 Trang động (Dynamic Page)
+8@<E8%&' 3)&4&U8I[
"A*f@Y$--vI$&; -_(@8>
D$-.f$&.+$2-*** e I["A6=d8/*h
I["A2=@5o-&px."J(&Xx<[!
Y$-I$=$*Q$=$8"J(&)!@Q d@'3"A:[
K*Q8&>I$=$[E2%&-vI$-_@8Df*V?"AI8&)
 e !I["A[@)&4&!@L$$Q$=$OmLoLQOmLp.3
"A)"H:@{I]*C!I["A; {I]<@I8&>2@
-&:[{I]>!v$-I$=$*Y$-I$=$/@LQOmL:@{I].I8&
>E2%&-vI$-_@8Df*
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f/8I8&) e I["A&); ="88-8I$-_
"HL$$88-8I$+$*CI["A@xI8&>2
=@-&:["J(&!I$=$*Q$=$E "J(&="88-8I$I8&>
E@8Df2%&-vI$*

I.8 Sử dụng Internet Information Server như thế nào ?
L$$Lr8Q$=$U2G 33G%&8/
W328&*+58>:I["A@Q$=$@Y$-I$d
B>:I["A6&I$=$@Y$-I$*f@J]:
91&'L$$Lr8Q$=$><I["A-@-@
U8@EL8$8)><]2!L$$*
+29-I8&)5 8:& E==2GI["AU8
L$$Lr8Q$=$*
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I.9 Các kịch bản Intranet
D@>oY2& p8>:?< L$$Lr8Q$=$
=!@Q$=$*Y$-I$=$U8Y2& >2GW3E8v$-
: 33"Av2&  e 8 =!
88-8I$Q78) e &)&1&)X8ot$$O$IIQ$=$p*
D@EE!>6&-@ ;ov2& p.-@
;E)L$$Lr8Q$=$I$=$U8'*f@I$=$&
<"H: ]< =%&K1E*
I.10 Các kịch bản Internet.
L$$Lr8I$=$>:@Y$-I$=$L$$
=?"A/8I8&)
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DQ$!.8>: e =E&)&1!
Y$-I$=$=I["AAxm8$:@"&
Y$-I$=$*
Q?< L$$Lr8Q$=$=!Y"vICD>:E8
I$=$>6&3G*V?"A@)>6&I$28&

!.>:"HL$$Lr8Q$=$:&)6J8I$)=!
8&.=8B>:"HtOQ: e &); !L8$dL$$*
Đỗ Hải Nam - KHMT - K46
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Đồ án tốt nghiệp
C6&29-]2!L$$`%&8! 43-8
t&$I=-98_J8)?U88=L$$"H:/
>o 82$Ip[%&85*+< )8<6; 
29-Z*
CHƯƠNGII : TÌM HIỂU WEB CACHING
II.1 Các thuật ngữ cơ bản
D&)!2=2(=6Y$-88Ia':&@
I]&;J8)<"H2?2(=>BJ
&;J&wU8L$$*
II.1.1 Client – Server
\)J2(6:)"@(]3"A
Y$-*
- Clientk'3"A"H:; 2]=!A?[
)&4&&1 "9=A*\>'"&)(Y$ '-; o$"p
dAI["A&]2*+$"A1E)
)U8I["A&]
- Serverk'3"A"H:1 ;2]=!A? A=A
)&4&&1 "9=A-_[ 3ZE ?8)&4&*\]
=!(]&1 "9=A!.')E)
(] 43=< -( 43I$=$= 4
6I$=$*
f@)UY$-oY$-I$=$p'%&K=&1 =(&); !
@; < &)>*D&)>'>:,
r$=G-.'d>:"J(& 3E }E
IZ"J(&*

D 6 Y$-' 4&   )&4& U )& =(
"v8"*+)$'"v8"XI$=$*D< )
?>[)&4&38U8&)@=!@=
X ?8$'bo{SSnp>"v8"=6'
"J(&=G-d'=!2?!&-'2MSSSSn*
\)?@Jd:-U8(]Y$-*D]@;"J
(&-8B8]@&)6"J(&-Z=;)4&I["A
Y$-'&);*
Y$-$"H</'"&)(o-vI$p*CJ3"A
)}EC$I8 $=fIrL$$ $*fA?U8J
'"&)()(9@"&U8@8Y$-
+>@I]<!I$=$<I["A@Y$-*O 8$
DDmI$=$@JI$=$Y$-"A=q ?*
Đỗ Hải Nam - KHMT - K46
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C$8 $.fIr=)2B>@I]I w*C4&
1I w'6&; &=(&GU8I$=$*f@I$W
C$'>:;MS(&)&4&@)*D< )'
 43# 466& <2@w;:>:
3<6&)&4&@5=;)*+>16&I$E)6&I$=$
II=!8&:>: 3<,(8)&4&=;)=`
A=A=(" `*
II.1.2 Proxy
f@'&8>:E@=!=8`U8I$=$dU8
$_A?8)d$E8)&4&*~&4&< A=A
Ed&):%&8 )I$=$2*f@ ) --
"9=&4>:=E( )&4&!2&): )&4&*
+ )<I["A-@>> ?8$%&8r$v8
U8E='<:[K)&4&%&88

32<:28Z ?8I["A*
II.1.3 Cache
f@&JE- 3U8'.@(]
A<6&2:=(&J.&1 =&•(&*+8$&-
 3>&@?>:&J<o8$8-$p:8 3=
-^&A)&4&*n13$8)I$=$6&>:>
8$*
- Mạng lưới cache server (caching mesh)k(]8I$=$ ]< 
E@=!8&*
- Web cache server cục bộ (local cache)k8$I$=$E)H@E
OC=!$*I
- Web cache server cấp mộtkY$-8$I$=$$U8I["A2]
 *E)4]EA-@*
- Web cache server cấp cao (upper-level cache hay entry cache)k'X ?8$.
18$88=E!822]}$
8$I$=$1 8*DEY$-8$I$=$1 8>Em8$
8$<2] Y$-I$=$*C=;).@E!'
U8Y$-8$,8?1]*
II.1.4 Các đối tượng Web( Web Object)
€\]<•Z)>:<:&E"J(&28&I$=$
}Er$8&".r$‚ .**\]<Y$-'>@I]d:%&8
/2?!.2:&r$oDf.8$.8&"**p.8E8r$.
8,I[841*
II.1.5 Nhận biết tài nguyên (Resource Indentifier)
C;-&)B@J2(-U82
5Y$-*\>>:8)98,U8@]<Y$-*C>B]
98,U8@8)I](E*D'88)/
 Universal Resource Identifiers ostLp*+5'<I["A
=)?*+8$I'<I["A:;-5*
Đỗ Hải Nam - KHMT - K46

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Đồ án tốt nghiệp
Uniform Resource LocatorsostIp@"E"AU8stL*!)
@==?"A=:stI
 kuuvvv*&*$"&*=
 kuuvvv*8IIP $*uI $Iu"-2*I
r kuur *r$$-I"*u &-ux$$nQutOf*DƒD
II.1.6 Các giao thức truyền Web
++$=Q$=$'I["A83=;&):28&
:8W8&*+83<)"U)"8
83D+muLm*D$ Hypertext Transfer Protocol oDDmp@J
83 W-1(8)-Z='5<2Y$-*f@I]
J832x$D8r$moxDmp8)l $'=#<I[
"A)8)*C8@I]83!&1(4)Q$&$
Q2e8)$oQQp8)t$8P$D8I motDmpB&)
<I["A*
II.2 Định nghĩa Web Caching
hg&;Y$-+8?=(&):- )U8(&Y$-X
Y$-I$=$4=!Y$-$*C'&.I["AY$-$Ia
,;1)@q11 2)&4&@st. ?8%&KEIa;
1)?&<=Y$-I$=$>I]<)&4&&1 "9=A
1 *Y$-$)&4&(&XY$-I$=$d d%&8
Y$-8$I$=$8) )*Y$-8$I$=$>3^Y$-I$=$2
'X ?8$=>3^$2'X ?8Y$-I$=$*+3
^U8Y$-8$I$=$&J(&Y$-o>:8Df.
'd( pE=9?4=!I["A: &):
=66&4H@(&%&8H@2]=">8
=6=E8?I$=$4&8
II.3 Tại sao phải sử dụng Cache đối với Web ?
\='>2(<8"&)(Y$-*C>&1

@(&%&2G -WY$-*+58)$e@
=?"A=6=( -WI*+58)I&)iI8&]I
< -]!8)U8J@y+&1-J&]I=
-5=!I]<!!--&*+--&'E-
&]I=!I]<b![8I*\@>:[8
I=&8&]I>*D$$'Y$-8$IBE@
[8I=  ]*
N<??U8Y$-8
„8Y$-<8"8o8qp
„l-GI["A
„lI]4&); EI$=$]
II.3.1 Thời gian trễ
D8q?28"J(&<&):X)
2*f@&]2U8=(qE?aE*h
2]<I["A]8'>Ia< t&$8)
Đỗ Hải Nam - KHMT - K46
Trang 11
Đồ án tốt nghiệp
Qv*h>< 4)<'>IaE-b1
> $*V!J83;)D+muLm=(1>'
=!=(&)6E>*V'=;)=(&)6EIa)116&
8.]@U8E=(&)6*
II.3.2 Băng thông
nG?"&<&)6"J(&%&8*V!
)&4&"J(&2%&v$-8'>Ia2(<-G
*h>Ia2]-G:"J(&&)6X)I$=$]>
1)&"J(&8$*Y$-8$'-GI["A-Z&
"J(&DDm*\6&)>:>v$-8$G(&%&U8-G*
C&@EMSS"H22>v$-8$'Ia<<
MFS"H2>v$-8$*

II.3.3 Server Load
+B]=(-G'=(82I["A
I$=$]*+I$=$' 3A)&4&X ?8$*f@I$=$
'00Ia8I=!I$=$-;*V'=;)<Z)I[
"AY$-8:88""J(&U8(]I$=$*
II.4 Phân loại Web caching
C@"&U8@8Y$-'>:<&JZ6&=9?28&
"/$"#J8$=I$=$]*\4&'"&)(
B')"(]8$>*C8/>nvI$8$I*
D $8 )o )8$p2< 1)&4&U8$
@>*+&]H@(]E"(>:<dE4&I$=$
]:&JJ 3&)*
II.4.1 Browser Caches (Client Cache)
+'"&)('B)">(]8$*f281
5n82'"&)('>/E888=X8$8$U8>*
\]<8$>:r$Ei8d>:-@!
*
D2'"&)Y$-C$I8 $)&4&-E 9$2
8i8"8-8&*fIr')&4&-E4 6&
2:2?!8$"i8U8-E-8&*D'8
I["AMSPMSSfn28i83"nvI$8$*
II.4.2 Caching Proxy (Server Cache)
E8$)_@I$=$E!6&$=
6&I$=$*D.>2_H@(]E)@E
Y$-$8)@DDmI$=$>*h]nvI$8$I."9
=A8$)>: A=A6&&I$H@5*h>6&H!
G@v$-I$E@:'8 $I<I["A
nvI$8$*
+8 $I'4]=!16&W3&1
"9=AY$ W)!.E/.=(3&*+8

Đỗ Hải Nam - KHMT - K46
Trang 12
Đồ án tốt nghiệp
m$I'<dZ8$v8)o&$p8)>@2'
><I["A:>: A=A@I]<!1*
II.5 Web caching hoạt động như thế nào ?
D1(]8$6&I["A@-@&)0:9
:&1 ]<o8)(&Y$-p.1=!6&2(
]<><&8$*D< ]<<)&4&
8<&Ic8$'8$I$=$Ia[)&4&>I$=$]*
f@I]&)0<; 83DDmuM*S.DDmuM*M=@
I]2<; -ZJ%&98$o>:I["A
-vI$8$d%&9 )p*
II.5.1 Các nguyên tắc chung
„C& 4&6U8]<8$-2 &]<'8$
2&]<>*C&-;o-=8"8p2&1(.
4!8$Ia"1&]<2:&o&8$8-$p*
„C&]<>)&4&;8)-;.>Ia<&*
„f@]<<&<`P…r$I…o>i8>:<
[!$24I2:8U8I$=$]p
PC>>8EoE@$"E@E-@p`_
28r$Io8%&Ep
PC&@-vI$8$X:9]<=]<)
<"1&2:8@ !>*
PC& )8$![K>4)=><I[8W!>
]&*+]<r$I<1) X8$242:
8=!I$=$]*
„C&@]<<B.I$=$]Ia<)&4&;]<
d-8$_]<>=#`9I["A*
7&';=2:8$d?…r$I…U8]<J-(

 %&8/5 8$=(=!]<*f@]<…!…Ia2
"A3X8$.2@]<… ;…o=8"8$"pIa
[E@4J8XI$=$]&>2>'8)W*
II.5.1.1 HTTP requests
+$'&I["ADDm258 =! )*\6&)B
52$)&4&@xDmGl $st*+$Ia88J)&4&
228&1)]=! )I$=$B]=!I$=$]*D
< )')&4&<8&! )<$)&4&
proxy HTTP.
II.5.1.2 Yêu cầu đối với server gốc
D!8)$@)&4&<[I$=$]*lI[8
)&4&@stI8&k kuuvvv*8*$u"$**h+$2
1&'I["A )'>Ia2] !I$=$]ovvv*8*$p:
[)&4&)*
GET /index.html HTTP/1.1
Đỗ Hải Nam - KHMT - K46
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Đồ án tốt nghiệp
Host: www.nlanr.net
Accept: */*
Connection: Keep-alive
D')&4&)6&$8"$I=!J'8
8Z)*†)81)_st<8{ 4*`$%&$I
$o"`4&p,-8 4U8st*D> 4I8$
<  &1  (    4 Host $8"$* Host $8"$     @  d  :  U8
DDmuM*M.><I.8)6&v$-I$@I$=$=;Ko@
98,Lmp*C&I$=$]2<"8'Host$8"$"H:
"J*
II.5.1.3 Yêu cầu Proxy
h+$8 =! ).)&4&B2>I2-(I=!

I$=$]*D&)"`)&4& )Ia-8@st4)U*
GET HTTP/1.1
Host: www.nlanr.net
Accept: */*
Proxy-connection: Keep-alive
DDm88@I;k)&4&= 3>:<8%&8@
I] $I38+$=Q$=$]*f@I]DDm$8"$<9i8
$"$"o&]!:&]p=@I]  o:!:p*
"$"$8"$'=;&):!(]&]o+$=Q$=$
]p.=-''>2 <,I[8-! $I+2$$8"$
B$"$"*C<E  $8"$>i8"
(]&8=> <,I[88)"&):!2
<5<8=9?!*Proxy- connection=proxy- authorization
$8"$Z"E  *f@+$I["Am)‡$$8"$:b
)D+m2]@A-Z=;)5<I["AE:
)&4&28*m)‡8&ˆ8$8"$38IU)(:
>:&); = ).2 I$=$]*
II.5.1.4 Yêu cầu không phải là HTTP Proxy.
+&]H58[$ $I][=!)&4&2 
DDm*\]=!+$'5&<832
DDmxDm.DDmQ6&)>i855&-8
  =!xDmI$=$*D&)4&8 )
2K=6xDmI$=$.?='=;)-E2:dxDm=8
)*
II.5.2 Khả năng lưu trữ
fA??U88$?&J@I] 3>;
<XI$=$]*f@ 3</<&J>i8>>:
<I["A: 3<J)&4&8*V!&"J
(&)&4&'2TF‰ 3<&J*
Đỗ Hải Nam - KHMT - K46

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+8$%&)9&J-_=($e 428&U8
)&4&= 3*C>>:2:8I8&k
„\ 3=6-;
„+ 3)&4&
„\ 3+8$P
„+ 3
„+)&4&2:8?
II.5.2.1 Bảo mật
f@J]:9$>:&J> 3=6
-;*n82?,E-;8-)&4&>< 3
8)28)>)8%&' 3)&4&*DE-
;8F>
1XX:D%&'8"98<
2XX:~&4&<;=8<[K
3XX:Q$=$8!+$!@=9?2
4XX:+>@)8=!)&4&U8$**
V?"AO&$8<)&4&.8)&))&4&2
E
5XXkf@)8I$=$]=!@)&4&U8+$
DE>8"A1{SS*DE)>i8)&4&
< 3*
II.5.2.2 Các phương thức yêu cầu:
C]2:9>:<&J> 
3)&4&*n"!)>:8@= 3=2G&J
U85*
Phương thức yêu
cầu
Khả năng lưu trữ

lD
fd9<&J
O
+>:<I["A:; ;&J!
mŠQD
fd2&‹CIa&&Cache-control
$8"$I e
msD
h-8&J
D
h-8&J
ŠmDLŠCQ
h-8&J
DtO+
h-8&J
D8>:;1)lD 3)&4& W-1= 3
)&4&lD'd9Ia<&J8$*D2>2
3)&4&mŠQD'>,>:<&J2 3U8
>8E= e Cache-control8)9d9*
C'?2)&4&mŠQD<&J*
Đỗ Hải Nam - KHMT - K46
Trang 15
Đồ án tốt nghiệp
II.5.2.3 Thời gian kết thúc và tính xác thực
DDmuM*M&1 8:>:"&)'2=!I$=$]*
E8=-o=8"8Ip*+8)6&00_
I["A>:<;J; ;1*
f@I]Y$-I$'[J $P$ $"*\6&)>i8
8$ 2:88U8 3=!)&4& $U8@I]I[
"A*m$P$ 8'<I["AI$=$]>&]2

;1)1&=&); I$U8/E&]@"&=#<&
J*+>8:I["A $P$ $>; Expires$8"$-_=!Date
$8"$*V?"A
8$kQ&.SMO {SSMMŒkN{kRŒlfD
 $IkQ&.SMO {SSMMŒkN{kRŒlfD
f@28>:[@9)< K8)9€S•
 $IkS
II.5.3 Cache-Hits, Cache-Misses
h+8$;<@)&4&'>Ia2:8$& 3
)&4&)<&J8)8yC& 38<&J'> 
A&):)&4&)I$=$]*h@)&4&8<(
!>-8'8/>+8$PII$I.]<8<&J*d
]<>:-9>8:"@]<!*+>FSPTS‰
)&4&8$PII$I
C&@]<<88'8/>8$PI*D&)
8$ %&)9$&J 3!8)&*f@ 3
!&8E2<'1)<E>B*f@ 3
!]1='58!$@8); 3*V'=;)
52>8q=2]-G!I$=$]*+58/
5&=8"8$"I*C<E]=!J 3B'5B 
)&4&2:8]=!I$=$]
fA?U8=(2:88)&4&!I$=$]& 
3=#`9*C&&)8)W'58Ia2&]$
;J 3B*DDm/5J)&4&6&2(o"8
$%&$IIp*\ 3EJ)&4&6&2(d@( €C
f"r$"•d-@@ 3!*
C:>:->@ 3!8) 3B*
DDmuM*M&1 88:>:9<>"8=expires
$8"$=8P8$8$*l9$ $I$8"$?)=E
>>Z 3B*V?"A

8$kf.M•x$-{SSMSMkRŽkMTlfD
+`98P8$',"#8-I]) 3`<
$!*V?"A
+8$Pk8P8$z{MŽSS
Đỗ Hải Nam - KHMT - K46
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D'E)8- 3)`!=`Ž
2:X2><I8*
II.5.4 Quá trình kiểm tra.
† 4'583&%&'2:8U88$
E8$I8)8$PII$I*C8)I8&2;<@)&4&
=6@]<.'8$Ia9?< (]=!I$=$]*
C&]<<&=#`< ('I$=$IaE-_@
( 0DDmNSRoC"r$"p*C&2'-@]<Ia<[*
DDmuM*M&1 82i&;:8>:2:8>9:&]
H]<8)W8IP"r$"=D8o$)D8I$8"$p*
II.5.4.1 Last-modified
4& 3DDm'-88IP"r$"$8"$:9
82]<&)>I8)W4&]HI$=$]*
8IPf"r$"'888lfDol$$vf$8D$p=!=9b
1)*V?"A
DDmuM*M{SSŠh
8$kQ&.SRf8{SSMSNkFTkRFlfD
8IPf"r$"kx.S{f8{SSMSRkS•k{SlfD
h8$9?< (U8]<'>B[If-modified-
since headerU8)&4&6&2(lD
lD kuuvvv*8$*$uDDmuM*M
LrPf"r$"PQ$kY$".MRx$-{SSMMFkNFk{ŽlfD
C&I$=$8=6 3NSRo"r$"p']<

8$=#< (=< )'8$ ; ;]<:>
:8&!1 3!U8DDm$8"$}EDate
8)Expires*C&I$=$2E 3NSR'8$Ia$e 3
XI$=$@@"&!8)=]<>=  ]
$*
II.5.4.2 Entity Tags
DDmuM*M&1 @2:>:2:8>P8o)
8Ip*f@P8I@&#&"H:;"E@:(U8
]<*V?"A
DDmuM*M{SSŠh
D8k…Œ8RP{TŽ$PNF-NŽ-Ž8…
+8$IaI["AP8I:;?< (U8]<=!)&4&
If-none-match$8"$
lDu"$*DDmuM*M
LrPC$Pf8k…Œ8RP{TŽ$PNF-NŽ-Ž8…
Đỗ Hải Nam - KHMT - K46
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C8)2;<)&4&I$=$]I2:8"J(&U8]<*
C&P8IoŒ8RP{TŽ$PNF-NŽ-Ž8p=#`< ('I$=$Ia=6-
NSRoC"r$"p*C<E'I$=$Ia-b%&8LrP$P8$8"$=
[K)&4&-'*VB/4>Ia=6-
{SS=!@]<!.8); ;@"&*
II.5.5 Thay thế trong cache
+8$Ia8)&>-94)=2>]<BIa-9
>8:J]<!*D'+8$Ia@=
9]<*D'9U8]<Ia%&82
G>>:<)&4&E@4J8*+83&. :=
88@I]69=6&;8)+8$*
Đỗ Hải Nam - KHMT - K46

Trang 18
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II.5.5.1 Giá trị ít sử dụng gần đây nhất (Least Recently Used)(LRU)
ts@J&;8)"<I["A-Zv$-8$I*
l&;)=q(*C>88<:&%&]
/*CU8>>.tsIa>8-bJ]<>2
<&); 86&1*l&;)>:<
J"8I*DE:2]<<&); >Ia
<"&):4&"8I*V2>]<?<I["A1Ia
00@"&):&]&]"8I*D&)=16U8&;
)?>2%&8!2?!U8]<*nE&]&@
]<=!2?!!8)6&]<=!2?!b*+&
)>aH)&@=I]&U8%&9*C&42(-G
'-EIa&]@]<>2?!!`&-EI]4&); 
I$=$]•]<>2?!bEI8/
< )*
II.5.5.2 First In, First Out (FIFO)
xLxŠ@&;;?`ts*\]<Z
)'H@1 -;I8&2=*l&;)2%&8I
W-U8]<*xLxŠ'?<I["A&>'><I["A
8$ $I*
II.5.5.3 Đối tượng ít được sử dụng (Least Frequently Used)(LFU)
xs'Bts.8)='=(/8"8)&
]8&); '"1&(&;-]=!&;)I]4&); *
xsIa8)J]<I]4&); ?=JEJ]<
>I]4&); &)*xsB,<I["A
I w5B?<I["A&)*
II.5.5.4 Kích thước
l&;"82?!I["A2?!U8]<@
d:?:&?>8-b]<*\]<=!2?!!1

Ia-9>8-b4&*l&;)I@2i&;B*h>+8$
Ia&EJ]<>2?!b2>'I]4&); !I$=$
]:2:8IaG=2>Ia8W-GU8&)6*
D&)(8)''I["AY$-86&I["A
&;2< &;Z*V'=;)%&'[KIaZE=<
K*
II.6 Sự kế thừa của các Cache.
h8I["A@Y$-8'>:>6&!E=6-@!
?='=;)=(2X88$@J6&8<*QI0 
 +8$I:@)>:2<=!J2*D
'X82+8$I.! 1 1Ia&):J8$PII$IJ! 
828$PI<'1)d)&4&>:&):
I$=$]*V(2X8+8$'1<%&8='2>>>:
(&G=(U8(]Y$-*f@I])&4&2>8$)'
Đỗ Hải Nam - KHMT - K46
Trang 19
Đồ án tốt nghiệp
Ia<'1)8$U8>U85*\6&)Ia-G
&)6YOC=G]@"v8"
II.6.1 Cache kế thừa hoạt động như thế nào
Y$-8$>:Z 3E d29'<*+58Ia
I["A&;J8o 8$p.o"p.8$&@oI-p:
]%&8(J888$-12•=!8&*
f@8$'Ia[J8$PII$IJ8$8U8
>*+8$8I8&>Ia&1 U8>J 3X8$
>IZJ&8)I$=$].8)X@8$2*+8$8>:I["A
-G!I$=$]: 3J)&4&X8$U8>*'=a
"!)/8=6@8$X82
II.6.2 Các lợi ích của kế thừa Cache
II.6.2.1 Hiệu năng

(&G'&/&]8; =(]2
X8*D&)(]82X82 6&42'.>2
-<00(]Ia(<(&G*C&-E&]'2
(&G]'-E %&)96&'%&8/]=!-E*l
-Gyl@q*nEE8@(]=(I(]
(&G+8$U8-E*V;):>@(]E@]'45K
J:I8&k
„f@I]]<2'1)8$U8>Ia<'
1)8$U8>U8>*8)>2-E>:;<
8$PIX8$>
„+8$PIX8$>'< -]8I=!8$P
II$IZI$=$]
„+8$II$IX8$8';I=! 3X ?8I$=$
]*
C&@6&2()2'(&GE
@8$U8-EIa-9Z*&)5E@58)I8`
ZU816&]*V?"A&8$'2@;
E '>>:;I=!2] I$=$]*V=
U85B>:8)W$8.@)>8$8E
@18J) $>EE@@;E
Đỗ Hải Nam - KHMT - K46
Trang 20
Đồ án tốt nghiệp
II.6.2.2 Thay đổi quá trình định tuyến mặc định
+8$8'1J&?2-E4G]@&"J(&v$-*f@
=?"A=(=<%&8x$v8*\]=!W3'=(I["Ar$v8:-
=(E@-@U8/*+>16&::28@r$v8*f@I]'G
d2I["A>:2] =!I$=$-*/
2]12]81W-8WDDmo 
ŒSp*D< ),>@:>:=<8I$=$-

%&8r$v8 ).Z>>:<d8$*C&-E>@
8 )E@-@U8-E'r$v8 )8$8U81
)&4&U8-E:8-*
II.7 Cách cấu hình trên các máy Client
+>82i&;-E>:I["A=(1&'+$*
f@J2i&;B>1&'-_8)o8&8r&8p*+$
Ia<88@8)6&98, ):I["A*V2i&;3{<8
8-ZC$I8 $>1&' )@o )8&r&8p*\]
=!1&')''"&)(Ia@@E(‘8=8Q 
!)&4&*\EQ Ia8=6'"&)(@"8I98,
)Z>>:&):)&4&*+1&'@IaG2:
I]I=!1&'-_8)*V?"A&'"&)(I["A )
4&"8II8&>>-9b' $"8IIa
<I["A*
fd"H1&'@'6"’.>)&4&&I$ >98,
U8r$‘8=8Q *\:>:EX<-!)@I])69I[
"A@83>v$- )8&P"I=$)*h82Z@@'
"&)('>IaI["A+mo)8I+r&8mp=
CQo8C8$Q)I$p:9 )8&Pr&8I *C&>
'1)'>Ia@E2%&U8I >-04&I["A8
)*
II.7.1 Proxy Addresses
+B1"9=AL$$288)xDm' )
I$=$@98,-898,Lm=I]Wo &-$p*D&)
2]J"9=A2 $I'2>Wd9*V'
8>:>€2]xDmI$=$Er *I *$•32>_€I["A
)E )*I *$•*f@98, )'&2“=!WU8>*V'=;)
$d9'8>:=5I8&"1&81*V?"A
MT{*MŽ*R*MkŒSŒS
I%&"*8$*$kNM{Œ

)M*-I *$kŒS
fd"H>2>Wd94& $II["A
I8&kNM{Œ.ŒSŒS.ŒSdMSŒS*C)8)'4&Y$-8$I'>:
0$)&4&6&WE@:*V'=;)>: 3
<])&4&U8"H*Q8&)8Ia3&1&'
-_8)]=!@+$*
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II.7.2 Cấu hình bằng tay
C888=(1&'-_8); @98
, )@d6&832]DD .xDm.QQ*D
'@ )'<1-Z=)H@98,m)<I["A
183*D&•&@=A?I["A )U8-E-8>
:48)241&' *C&-EI["AZI8&r$v8'-E
>Ia)&4& )1)&4&U8-E*D&)1&'-_8)
'B>@I]<:*C>Ia)&4&-EI["A:1&'@I]
<!.8]=!J"H')&4&@
I=|*+@-E &1 JJ'"&)(
28&= -28&U8H@'"&)(*h@ )-9
''"&)(Ia2[2] 8)I["A@ )2*\>
J)&:U8=(1&'-_8)*Q8))8Ia1&'#&@
'"&)("A1(8)>L$$ $*
II.7.2.1 Cấu hình Microsoft Internet Explore
\:1&''"&)()-E/$&DI8&>/L$$
Š I.8Ia1)>T8 /D8-$
+/OCQ$I:1&' ).E)@[8IW&1(I8&>-E
; 98, )=WU8>'"!)*
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C&-E&]I["A6& )28&832
8&'-E>:/5O"=8$"*h>-E>:6 )2
8&]=!83'"!)*
II.7.3 Cấu hình proxy tự động (Proxy Auto-Configuration Script)
m)O&P+r&8Q omO+p@2i&;<2:
20 AJ=46EU8=(1&'-_8)*D8)='=(1&'
-_8)98,U8 )''"&)(Ia@E)@I 2>)&
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4&*h>>Ia=6@"8I98, )'"&)(>:[
2)&4&<&):*
Q mO+'<=-_‘8=8Q *V'=;)&'"&)(
<‘8=8Q 'Ia<mO+*C$I8 $I8mO+=8=
V$I{U8'"&)()=fIrB8mO+=XV$IN*
\d:]1U8mO+? e %&9>:1&
'E24I8( U8I["A*C&98 )8)W
'%&9"q"8)WmO+I :8&!I8)W>*+
'"&)(Ia;=6mO+st=/:5-04&Ia
2&1(5>8E)X< "H)&4&$8"
E*
f@d:2B<=(1&'-_8)
U8>?2G'*C& )4&-9'>Ia@]0
'J $&]HU8"8"8 )>;<
-84&*f@<'1)2'"&)(;<+$t$r&I$"
=8; 2]=<%&8 e o$&p*
II.7.4 Cách viết một PAC
DU8:(@mO+>FindProxyForURLop=>8
8I]url=host*l9=6?&2?>::[)&4&*C>

>:@d6&"`8&-_"1&81*
mtŠƒ~Ik 
QŠ+hQIk 
Lt+D
V?"A
…mtŠƒ~ )*v$-P8$*$kNM{Œ‹Lt+D‹
QŠ+hQI2I*v$-P8$*$kMSŒS‹…
h-E=FindProxyForURLop'-E&])">3
G ?st*\:>J-E>:82
E kuu$*$I8 $*u$uˆ8u{*Su$$Iu"$u )P=$*
mO+ <dY$-I$=$=I$=$ <1&':=6
9fLf+$P) $$8"$ 3U85*C&+$P) $
2; O 8uPIP )P8&r.''"&)(Ia2;
-<mO+I *V 4Z@U8r$) .pac=I8&>,"#
DDmI$=$E+$P) $1stLI=! 4Z@)*
lI[@Y$-I$=$E)O 8$8>:"`I8&k
Srm.conf.AddType application/x-ns-proxy-autoconfig.pac
II.7.5 Cấu hình cho PAC Script
h8==dmO+I I$=$'8 1&'-vI$:
>:I["A5*D1J'848mO+Q st1&
' H< =!'"&)(*
V!C$I8 $8dZ@ )8&r&8stH[8IW:
1&'=! )-_8)*D8/"z”m$r$$$I•Q8&>/O"=8$"
/Q$$m$I*+/€O&8 )r&8•'=ak
Đỗ Hải Nam - KHMT - K46
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Đồ án tốt nghiệp
+`&-EI["AfIrL$$ $'-E>:
 41&'-_8)-E/@use automatic
configuration script'=a=stU8r$mO+=98,*

Đỗ Hải Nam - KHMT - K46
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