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LỜI NÓI ĐẦU
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MỤC LỤC
DANH MỤC CÁC TỪ VIẾT TẮT
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oj` oE!&jK!!jK
`&!
U5I;
x` x&-r`EE @$-:2KLM
qox q&&oE&KxEE b9K-
b b;EE#&rE- h&?!,B
sw EEsEE&!wE MuIEE
pj p!EjE 75K:N!QKM
j@a jkiEKEE hI
`q `E!qE!;- ,B0B&
`l `;-El&-&rE- q?&>B
p E&&-E-E&
p
i/0D
o o&KE-E;E l80,8
f` f;E&!E`EK b5(;M
f` f;E&`&E! C5Q
@i @&&EEiE a*"KA
j EkjKKE!!&!-& @0&L&V

q r&qE ,L05
lj@ lEK&jE!!@- a?!8I;;:>
C0
q` q&&E`EE bC
` EE`EEKE @$;KLMEE
jo jKKE!!oE!-- h&;BL&V
ow@ oEDE!w@E! -tEE
l` l-&!`-EKKE :)
qjq q;-&EjKKE!!qEE qAUL&VZ-+;
@l EE@-l&&EE
-
@&&DB-*EE
` Ek!EE! l5-:1KLM
oj oE;E&jKKE!! i+;-5L&V
`bJ/abB^c
y

qb@ q&b!@r&
-
h&$UL&V(
lp l&#&!p 7>L&4?C:2
j &;;-&;&Er&E &K-I;UKM
jl &!!&!rEKE ;:>CKS0T,(
B-ISDN ,&K,&K`q l5!&KLM,(
CS @&&K&`&K&K @t@&&K&
@` @;&rf;E`!E! I;8F
GSM h-,&-`!Erl,-E
@&!
b0K(
bio bEi&oE!E 73L3(Z

jn
EE#&E&E &8-X
DANH MỤC CÁC HÌNH VẼ
CHƯƠNG I
GIỚI THIỆU CHUNG VỀ KỸ THUẬT CHUYỂN MẠCH
1.1. Một số khái niệm cơ sở
1.1.1. Khái niệm chuyển mạch
@?5-(D8U"$?0
:N!QKM0D&55/06488 ?
55/0,&TL0
?;06
1.1.2. Hệ thống chuyển mạch
x8U?5:2"58)5 5
?58)5:N:29-?5
zX{ 5?54:N:29-,LL
zc(L{6(!5+, ;Q"M
?54?e&4&A,Le&4&A?
5?;06
1.1.3. Phân loại chuyển mạch
@8?5$5?5 &4&K5
5?5>,BJl5?55?5
46 K:14(C#Q-*0 ?5A4?
`bJ/abB^c
W

;,?J?5 ?5,B ?5
4?5,6
l5?5-I;85z{VL
:1D8UC0"6:I D8U?
5:2&y&5;,J-I; CB;467?

-I; B;4C? 5?5!QKM
8uI,8?":(;,d,(6
:2-515?5-5?54 K"&
d;&8-:-:2K-84C
5&!= P4-("?(-I;&80
D8U#Q-*056@8&5-I; C
B;4!<:2"TN(BN&D
L:N:2#8-I;,F0C46
1.1.4. Kỹ thuật lưu lượng TE
auI-:-:2sz&rrsEE{:2-(
$CD&9$-%&55/06
lM3%&uI-:-:2-?B(I%&8
5(%&5:8T-:-:264
88 s-0M!QKM?:!QKM%&5,[
;:>;8;uI?L:18-T-:-:2;Z2;18
&!,(.+(6lM>,B%&uI-:-:2-
,[:8C?%&B50D&8
I8B;8;uI6
1.1.5. Báo hiệu trong mạng viễn thông
c8!QKM83?C?C0 5/
0,8-!"&X0-D&1C? -I;8
"DB-*56@8,84?;-5E+
3d5(TJc8,,8
, ,8:N,8& ,8-,8
 ,8,d,( 666@80,8:2CK:1
K53+,B6@8,85?
550(`z,-`kEKE-E;EEk{:2
8!e]|}6
1.1.6. Mạng tích hợp dịch vụ số băng rộng B-ISDN
l532;KLM!,(4M$;8(

0D&?5 8(L+,8L 8(
e?1?+e?1&?$;8KLM 
8KLMK:1+8KLML6@(c|
`q;MM8KLM?5 ?54E?
&;:> >;:> E?:1-+;-
E$U>:1+&:16
`bJ/abB^c
~

1.2. Các tổ chức tiêu chuẩn
@8t;•;8$;,L;8?8!B;t
E(I;8+3:N!QKMG:8$;
KLM4?-"&9:28,LeC$;6
bt:2&&-5Jt"
t;8;-*6t":2;8?,F($;,L
+(48$;:2$;I,F8Xt6
t;8;-*:2-I;,F€&I&8Xt
x&+•,&tx6@8t-D&1 
"?5(CB&-5t :I;%
t;8;-*6q:1-(!Xt
K/36
1.2.1. Liên minh viễn thông Quốc tế ITU
i/0xpzE&&-E-E&
p{-(X-3;%T48x&
 "6i/0xpTy "3J
i."00p|ozo&K&{Oi."
t4&/0p|zE-E&`&K&K‚&{Oi."
;8?/0p|qzqEE-;E{6
p|:2X,F]~4uI:&&8
tK:1K5L6@8L%&p|!EE!x-

D&1,8?563KM x6^ƒy]0B%M,8!Q
KM?-I;B?|?D&&K:N!QKM|5
0:Njl6
1.2.2. Tổ chức tiêu chuẩn Quốc tế ISO
Xtx`fzE&&-f&‚&r
`&K&K‚&{T8•,&t%&8x&6M%&
Xtx`f-#)t4&85
(-D&[5CI&X
4&KLM ;8?!"2;8C "6t`f:&
&8t4&,&Z$B8 "uI  "/
00UFf`-(t;X,
%&`f6`f2;81•,&Qxs@zE&&-
s-E&-@!!{?;8?8t583
-I;&•,&-uI„@]?;8?8t "
006
1.2.3. Viện kỹ thuật điện và điện tử IEEE
sssz!Ers-E&-&Ks-E!sEE{-(T
&uI-1$1;8?8t 
`bJ/abB^c


"|Q830D&;(tsss|`j
z`&K&K!j!!&{6
1.2.4. Tổ chức đặc trách kỹ thuật Internet IETF
swzEEsEE&!wE{-((TFx%&
85 C5 8$;,L8
-D&1!";8?%&)EE6l(!Z
>,B%&sw:J…KM EE DB-*5 8
C L ,BI CBKLM:N!QKM6
1.2.5. Viện tiêu chuẩn viễn thông châu Âu ETSI

s`zs;E&E-E&!`&K&K!!E{-X
t4&/0 ;-2I(-I;%&†G:%&
16lM%&s`[P2D8Ut4& "
/0 00C00D&8K/
 5C8%44;*#K"8
t6
1.2.6. Diễn đàn chuyển mạch đa phương tiện MSF
l`wzEl-EK&`kw{$;8t
?5&KLMK"&CBjl P28?KLMT
8KLMKLMjlG:-8KLM86
1.2.7. Diễn đàn IP/MPLS
q/gli`-(Xx;-2I%&8
$;KLM 8$;,L 8?:NKZ#3
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1.3. Quá trình phát triển của kỹ thuật chuyển mạch
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`bJ/abB^c
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
?5'&&li`&N^__]-!"P-"
2;&;:>?5:1zjl wo{10
?5;z{6
0:N5& !";$;,L,z(
5{ ,LD8&,L-‹5$;8KLM`
S&T56@85,&Z:wo jlEE&:2
?&!!5&-56@8I;(
T8;T 8;D&I;0K&:2?&
-&K5I(I;e;3&5I;6
`":F%&8KLMI;'5!•;+&y$
C31?5,(&KLMJI;,
0( !"0%&,L,CKS(&55
-‹6
10:N5`:1 8,L-‹5L8
3CDB-*C:2&X
8,LN50:Nh6
@8?5;B4(CK=-1[:>3
8;8:F-:-:2e;3&86UI >
C?8?5':2;8?E:1;-1;
K-E4&[&?5B,Bx`e
16b:1;I8%(9@`z@& `EE{:1
?&;&KLMzl`{:2U,K:1V&!"
&X-1-L!Q;8??56
1.3.1. Chuyển mạch mềm và hướng tiếp cận máy chủ cuộc gọi CS
b:1;I8%(9@`:2UD8U
?X855?5!&?54
5`67?"D8U?XC5C 

(B;8;4?"-5&(,L-&4??55
FBK541!"32;%&;C#Q-*(96,L
,(C?X&;:>lh@zlEK&h&Ek&@ E{:2
-;$B;8;uI?5C`r!k6
"$%&8?5C3-;C"
#Q-*(9?54B?B
C-5018&8&6EI?5
CU?5I-*:2",FX&;:>
lhzlEK&h&Ek&{ A#Q-*(9-%&,(C?
X&;:>lh@6
@?5C"8:>"?5
C:1-"CK=3:>6@8:
`bJ/abB^c
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
?%&?5C&-5-K?5,[;C
K"&$);88&K-I;UKMF6
?5C ;?5-0Œ
1;CC?%&Z($;67C-3
(DC$;8?5 0$;(
0:N5KLM1 -15B;8?8KLM
1%&8DBL56ad;MC ?5C:&&
&K-I;UKMFjzj;;-&&&,-EEr&E{ 
;•;:>3;CC?;%&8$;
8&6
@?5C:2#K">!F5 #Q-*0
(8! ;•;8;C-5-:-:28&67:2
#K"E$U;8 888€
?5G-M?5F>B>K
4-"#Q-*5<>6@0?5C-B3

(DC%&8$; 4;;35&K4B
8%&?5C6
1.3.2. Hướng tiếp cận phân hệ đa phương tiện IP (IMS)
7?"(M&5K(15LE:1
4& 5;hKM15yhC
86^___ yhzy
K
hEE&&E!;•E{'-I;
8+3%&m@qljoWzmE-E!!@KEq!l-;-EjE!!
oE-E&!EW{ 4--:&&8?5C
5-‹K(6`"&XB:F1)5 8
&K5 !";8?%&8KLM0K(
:1!";8?%&yh1h6hyh:&&$C&6
yhh0V$;8KLM:5A-8KLM
&;:>0D&8&KKLMF6
1.4. Vai trò và vị trí của hệ thống chuyển mạch trong mạng viễn thông
1.4.1. Các thành phần của mạng viễn thông (Telecommunications network)
i(I;2;,&T8)58:NCKS
&&&C?#8L?"8(&X0&
)6l5/0$;&K58-5UKLM/0
8 eKLMC:5 w&# C!-
8KLM1:EE fq :>5Q R
1.4.1.1. Thiết bị đầu cuối
,L-8&,L%&:N!QKM?&;1
5$;KLM6b&4C%-5,L%&
C'8&Z(eKLMz3KM:85 
8r&# R{6,L"?X0
&X83:2-56
`bJ/abB^c
]_



bU]6^6@8;%&5/0
1.4.1.2. Hệ thống chuyển mạch
b?5-;-‹%&5/04
-I;:NC&8,&z{6
ZEL3%&?55 :N&&
X?;D X?;-VX(5
+E, E-‹6
1.4.1.3. Thiết bị truyền dẫn
,LCKS:2!QKM?8,L&&8
X1&C83(8&43#86
,LCKS:2;-5,LCKS,& 
,L1(X(5 ,LCKS?; 
&8X6q"&0:NCKS ,LCKS4
?:2;-5T,LCKS!QKM8;-5 8;
!2D&,LCKS0!QKM0&-0:N
CKS6
1.4.2. Vai trò của hệ thống chuyển mạch trong mạng viễn thông
b?5zX KE?5{43
--I;$&,L;81,LK"&
L&V5z!,&{6b?5:2+F8L3)
564,&TI;2;8;:>uI?" #Q
-*;;80?1e801
?56
@8:2",F(?5 &(
;%&4$;83KLM86a5
`bJ/abB^c
]]


5&X 8?5F;5;
>?4?$;8;:>,X!;•;854B
$;CKLM;;)$-:218);
IG:,BK:vFK/K>6
l+KZ8?554;5;:4S"
%8>,B%&(?56b
?55/0'F(;;5;
$ I;&$-:205 -:2$#8
-:28#Q-*06
1.4.3. Vị trí của hệ thống chuyển mạch trong mạng viễn thông
1.4.3.1. Vị trí của hệ thống chuyển mạch trong mạng PSTN
bU]6y6L3%&X5`
hm Jh&Ek&ŽXD
s J&!s#&EŽX?;D&
bis Jb!i&-s#&EŽX(5
osi JoEEi&-s#&EŽX#&zX
`, J`,,EŽ,&
l5`-5/00(:2t4&Kp 0
CB-0?56b?5:2
+58KE5:29-X6ZEL3 %&
X5;&8-5J
− XXD
− X?;Z
− X?;(5&KE
− X(5i&-
1.4.3.2. Vị trí của các hệ thống chuyển mạch trong mạng GSM
`bJ/abB^c
]^

@?5350K(

h`l:2",F?5z``{64,&T(!
8J
X?5l`@J"80-D&
-I;gB;4(9 DB-*,& $1858
?"8(9-56l`@DB-*8c`:2&,L
8>!FK-;•;&4I;I80C,& L
3,&?488;;Z2;zbio io{6
X?5Q&‹hl`@Ja1858:
55L&5EE6hl`@"C?8
(9e5K(55L:2-56

bU]6W6L3%&X5h`l
1.4.3.3. Vị trí của các hệ thống chuyển mạch trong mạng NGN
`bJ/abB^c
]y

bU]6~6@$)5h
@0CB%&h-?54 UI8
?55h-8,LLoE6@8
X&:2;&8-1;5-< 8-1;
-1&D&8&KFt6
`"0%&#Q-*(9>,B?5`'
:28&e;%&&I?56`"04[
(,L8N9-?5C&,(C?X
;:>lh@zlEK&h&Ek&@ E{&8(9z@& 
jE{ 4&A;QC?)516
. Đặc điểm của NGN
`QKM0?5Cz`r!k{&8,L
?5;zb&Kk&E{TC6@85%&eKLM
<:21&0D&!"C?%&(,LX

K$ ,LXK"&0`r!k:23:
•8•%&h6
l5(M5K- LK(6@8-53:2
CBEuI?54 #:1!d;1&-!Q
KM51uIx`:li`6
l5,0($;&KLMJ5CKSD&1
0mqlzm&E-Eq!l-;-E#{&qmqlzqE!E
m&E-Eq!l-;-E#{6
`bJ/abB^c
]W

2.4. Cấu trúc NGN
bU]66@$)-1;5%&h
@$)h,&T~-1;J
− i1;I;KLMz!EE&E!!-&E{6
− i1;CBKLMz!EE&!;gE-&E{6
− i1;C?z--&E{6
− i1;KMgKLMz&;;-&g!EE-&E{6
− i1;DB-*z&&EE-&E{6
Lớp truy nhập dịch vụ:c&T8,LI;$;8
18,L,&D&558;T 
+8;D& +0D&0:N0z0K( 
 I;0LR{6
Lớp truyền tải dịch vụ: c&T8)?5zjl‘{8
CKSz`qb mql{"?5 L
(9&8,&%&-1;I;K:1!"C?%&
,LC?(9(-1;C?6
Lớp điều khiển:c&T8C?(9&8
,&D&C?8,L?5zjl‘{%&-1;
CB8,LI;%&-1;I;6i1;C?4

(9,&1-1;KMgKLM6@8:
DB-* !48 3:1G:232;-1;C
?6
`bJ/abB^c
]~

Lớp ứng dụng/dịch vụ:@$;8KMKLM:KLM
50zE EEk{ BC:1 KLM8L&
EE80D&-1;C?R0:N
;8?5&!<4$C;&&K&-1;
6
Lớp quản lý:7--1;+,#!8-1;6@8
DB-*:2)9-JDB-*5 DB-*KLM DB-*K&6
2.5. Các thành phần của NGN
l:>D&&$);-1;8;3
%&h:20BU^6^6
bU]6}6@$);-1;8;3h
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2.2 Đặc điểm của điện thoại IP và mạng VoIP:
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• Nhiều tính năng dịch vụJ@,0C:N91&(
,&54?4C!--5V(,L
K$6
• Khả năng multimediaJ((9:N!QKM4?e&4
e&!QKM8KLM8:Cr-E &!=K- #E
UB%&:N4,&R6
0G45:J
• Kỹ thuật phức tạp:7?4:2(KLM5$;I:2;B4
(uI•35:2dE:JV!•-1
(#Q-*%&8,(@KEz@KE&KqEKE|bộ mã hóa và giải mã{
;B%&67TN>!F5%&5G:2$;
-801?4(&>4>"
x`zx&-r`EE|chất lượng dịch vụ{6
• Vấn đề bảo mật:l5EE-543(d;P2; 

44$C-5838& 8KLM8&Z!QKM
(>!F56
• Ngoài ra: 4?+;$C:0?!QKM:2KL
M); 0?8KLMt:J$; ,8
8666
∗
{…KM%&J
‘Internet Telephone:-,L:50:N:4
?583TN4?P2+0P2
550(`6EEE-E;EA4BC
I3&";e85!-6
+ Gateway IP – PSTN: 7?4?!QKM5155
0(`U&Ek&Ž`-(X;•;&X8
0&56h&Ek&4?";&54+4?!Q
KM2;18cn6h&Ek&Ž`4&&K34-J&
K15`&K15EE6
`bJ/abB^c
^^

+ Các ứng dụng mở rộng:>!F&Ek&Ž` )&4?;8
?&Ek&Ž,-E?4?";&X0&5K
(15EE6&4?;8?8KM:C
U(B&54U6
2.3 Các hình thức truyền thoại qua IP
^6y6]l0U@@
0U P83:2&,L(!K&K (
;E (!;E&E:2";15EE0D&
KE+&K56lP83:2$;(L&V&83 
I-'4?&X351&0D&5EE6
^6y6^ l0U@;E

l0U@;E-(0U:28>!10U@
@6l0U;•;:N!QKM834?"(95
`0:N:2-56
^6y6yl0U;E;E
7-0UF(%&0U@;E !QKMEE-;:>
--5&85`6
^6WCơ chế làm việc của VoIP:
a4E&;E 94!<5&3e 4-
3&&-63&&-:2?!&3!KZI8
+,??X6
2.4.1 Số hóa tín hiệu Analog:
c?K/3:>"K5!-046U,BK5
&:94:NFK5&&-K4(!-:2-188L
K&-?,?K/,( !;& ?X8L4K5!L
;-$46@4>KZ?"!"?X
DB%&!";8?-!"&N%&,L:29-KE&-
,L'4&B'6
`bJ/abB^c
^y

2.4.2 Lấy mẫu (Sampling):
3&554;X-:25]_a‚6
 -:2CI;F;$;>KB6q4?
,08C:2•;EwqlBql6@8
5:N15,Bey__yW__b‚6
"!<4(3-:>/:2?D&K:1K58!&
>!KMyW__b‚6U;Xt!4?:2F(Wa‚6
2.4.3 Lượng tử hoá (Quantization):
U;%&!4&3"-,?K/8L3#8P
S:2-$6lPS4?:28(8L! :>1,(zE

C&{%&S6`&"151,(:>1
KBS -:2PS!<:2!!81(I;2;8-:2Q8
(#$;#V146xL[$B8SZB&&
-:2Q:2#E4Z8L6`&48L8:2KZ
C6`";MTUK53,&A€"E:1:2-56
2.4.4 Mã hóa (Encoding):
lP-:2Q:2VL(8L!‰, 2;‰,4^~&
8L6x:1,KZ?8K$8L+K:>S6cB,3
A-5,?K/(-1O,VQ&&Q&K:1%&K' ,&
V;:&K:1 ,yV;8&K:1;M6c&
,:1U!<-+;-5‰___-PKLM56qZ,:1
:-Z9?•&,061Z9U(4
?&C(9TN6
2.4.5 Nén giọng nói(Voice Compression):
l+KZ.I'4&@lWa;!-;:>;8;:2t4& 
:4;:>;8;'4&8:2!QKMKM+,6
@8;:>;8;"'4&41(€>(%&@l 
N4IKM:2B%&CKS!6@d\ 8'4&
($;!<,L5C$-:2 +,-/•!6
`bJ/abB^c
^W

2.4.6 Packetizing voice:
lP94':2!8:2•-5 4;B:2&
;€ ?+4 U0DB4
€ 4-1U5&C(/ KB:F%&-5
E&KE3:1%&K-5zEK&&{G!<B:F6`-:2
K-5,4,[&!"DB!QKM,
0$-:2%&(56
2.5 Các vấn đề chất lượng của VoIP:

7A€>,B$%&-;B4$-:25:>
:>1$-:255`6@4y&!3DL$
-:254-J/ :2$46

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