10
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1 | |
1.1. IP-. 1.2. -7 IP. SCTP-SIGTRAN. | |
2 | |
2.1 | |
2.2 | |
2.3 IP/MPLS | |
2.4 | |
IP- .
, . . . (Grade of Service, GoS). : , / . :
(best-effort service);
(differentiated service);
(guaranteed service).
. , Internet. , FTP (File Transfer Protocol), . , , ( , , ).
. (Class of Service, CoS) . . . (soft Quality of Service, soft QoS). , . , . . .
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. (hard Quality of Service, hard QoS), , . IP . , , Internet. (, ) , Internet .
, IP-, (Type of Service, ToS) IP-. ToS . (RFC 791: Internet Protocol Specification/Postel J., 1981). ToS (DiffServ) Internet.
IP- , . , . IP - .
( ) . ITU-T E.432 (Mean Opinion Score, MOS). , 4 : , , (1).
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(Excellent) | (Good) | (Fain) | (Poor) | ||
, . | 0-1 | 1-3 | 3-5 | 5 | |
, | 0-150 | 150-250 | 250-450 | 450 |
IP . 2 IP.
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() | ||||||
) IP; ) IP | ) IP; ) IP | IP | ||||
: , .
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IP- :
- (Excellent), PSTN;
- (Good), , PSTN, ;
- (Fain), , , GSM, IP-, ;
- (Poor), , , Internet.
IP- ( 3):
- ;
- ;
- ;
- IP;
- (jitter) .
3 IP- | |||||
| Excellent | Good | Fain | Poor | |
| , G.711 | , G.726 V=32 / | , GSM-FR | - | |
| < 150 | < 250 | < 450 | > 450 | |
| IP- | < 1.5 | < 4 | < 7 | |
, .164, IP- | < 2 | < 5 | < 10 | ||
, .164, IP- | < 3 | < 6 | < 15 | ||
e-mail IP- | < 4 | < 13 | < 25 | ||
IP | 0 % | 3 % | 15 % | 25 % | |
() | 0 | 75 | 125 | 225 |
, IP-:
:
- ;
- ;
- ;
- .
:
- ( ) ;
- ;
- DTMF .
, IP-, :
, IP-:
- - , ;
- , ;
- ;
- , .
, :
- . , G.723 16,3 / ;
- , DSP ;
- , ;
- , / IP- ;
- , ;
- .
. :
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- , Excellent Good (, 64 /);
- , Good Fain (64 /) , , N-ISDN;
- , Fain Poor ( 25 /) , , .
[3,4].