1、 KSKSKSKS SKSKSKS KSKSKS SKSKS KSKS SKS KS 2006 12 22 http:/www.kats.go.krKS X 3511 OSI X.25 KS X 3511： 2006 (2011 ) X 3511： 2006 : ( ) ( ) : (http:/www.standard.go.kr) ： ：1996 12 31 ：2006 12 22 ：2011 12 29 2011-0657 ： ： ( 02-509-72635) (http:/www.kats.go.kr). 10 5 , . ICS 35.100.30 KS OSI X.25 X 35
2、11： 2006(2011 ) Information technology Use of X.25 packet layer protocol to provide the OSI connection mode network service over the telephone network 1. ISO/IEC 8208(PLP) X.25 OSI (CONS) . . a) DTE b) DTE c) PSDN DTE d) PSDN DTE CONS , . 2. . . 2.1 2.2 KS X 3002 ITU T X.213(1992) KS X 3503 ITU T X.
3、200： 1988 ITU T (Reference model of open systems interconnection for ITU T applications) ITU T X.210： 1988 (Open systems Interconnection layer service definition conventions) ISO/TR 8509： 1987 (Information processing systems Open systems Interconnection Service conventions) ITU T X.223： 1988 ITU T O
4、SI X.25 (Use of X.25 to provide the OSI connection mode network service for ITU T applications) ISO 8878： 1987 OSI X.25 (Information processing systems Data communications Use of X.25 to provide the OSI connection mode network service) 2.3 ITU T V. 2 5： 1988 / (Automatic answering equipment and/or X
5、 3511： 2006 2 Parallel automatic calling equipment on the general switched telephone network including procedures for disabling of echo control devices for both manually and automatically calls) ITU T V.25 bis： 1988 / (Automatic answering equipment and/or parallel automatic calling equipment on the
6、general switched telephone network including procedures for disabling of echo control devices for both manually and automatically established calls) ITU T X.25 (DTE) Interface between Data Terminal Equipment(DTE) and Data Circuit terminating Equipment(DCE) for terminals operating in the packet mode
7、and connected to public data networks by dedicated circuit ITU T X.32： 1988 (DTE) (DCE) Interface between data terminal equipment(DTE) and data circuit terminating equipment(DCE) for terminals operating in the packet mode and accessing a packet switched public data network through a public switched
8、telephone network or an ISDN or a circuit switched public data network ISO 7776： 1986 X.25 LAPB DTE (Information processing systems Data communications High level data link control procedures Description of the X.25 LAPB compatible DTE data link procedures) KS X 3308 X.25 LAPB DTE ISO/IEC 8208： 1990
9、 X.25 (Information technology Data communications X.25 packet layer protocol for data terminal equipment) KS X 3508 DTE X.25 3. . 3.1 ITU T X.200 KS X 3002 . a) b) c) 3.2 ITU T X.210 ISO/TR 8509 . a) b) 3.3 ITU T X.213 KS X 3503 . a) N CONNECT (request) b) N DISCONNECT (indication) 3.4 X.25 ITU T X.
10、25 ISO/IEC 8208 . a) (data circuit terminating equipment) b) (data terminal equipment) c) (registration packet) d) (virtual call) X 3511： 2006 3 4. 4.1 NL(Network Layer) NS(Network Service) OSI(Open Systems Interconnection) 4.2 CONS(Connection mode Network Service) NSAP(Network Service access point)
11、 QOS(Quality of Service) SNPA(Subnetwork point of attachment) 4.3 X.25 DCE(Data circuit terminating equipment) DTE(Data terminal equipment) HIC(Highest incoming channel) HOC(Highest outgoing channel) HTC(Highest two way channel) LAPB(Link access procedure balanced) LIC(Lowest incoming channel) LOC(L
12、owest outgoing channel) LTC(Lowest two way channel) PLP(Packet layer protocol) 4.4 PSDNPacket switched data network(public or private) ( ) 5. ISO/IEC 8208 X.25 ITU T X.213 KS X 3503 OSI (CONS) . 1 a) X.25 DTE . DTE ISO/IEC 8208(X.25 PLP) KS X 3308 DTE/DTE . . 1 b) X.25 DTE PSDN . DTE ISO/ IEC 8208(X
13、.25 PLP) KS X 3308 DTE/DCE . X.25 X.32 . ITU T X.223 ISO 8878 X.25 (PLP) OSI (CONS) . ITU T X.223 ISO 8878 X.25 DTE DTE PSDN(Packet Switched Data Network) . DTE DTE PSDN ITU T X.223 ISO 8878 . DTE . X 3511： 2006 4 a) DTEDTE b) DTEPSDN 1 2 . X.25 PLP OSI CONS . ITU T X.223 ISO 8878 CONS X.25 PLP . (
14、) ( ) . . 2 V . V.2 5 V.25 bis . 7. KS X 3308 . 8. ISO/IEC 8208 . CONS ISO/IEC 8208 ITU T X.223 ISO 8878 DTE DTE PSDN DTE V.25 V.25 bis ITU T X.223ISO 8878 ISO/IEC 8208 (X.25 PLP) ISO/IEC 7776 (X.25 LAPB) V ( ) OSI X 3511： 2006 5 . . 6. , . 6.1 . 6.2 6.2.1 DTE . NCONNECT . 7. 8. KS X 3308 ISO/IEC 82
15、08 . “NS ” “ ” N DICONNECT NS . 6.2.2 DTE 7. 8. KS X 3308 ISO/IEC 8208 . 6.2.3 OSI , ( ) 1 ISO/IEC 8208 ITU T X.223 ISO 8878 OSI N DISCONNECT . DTE ( ). . DTE . KS X 3308 . DTE , DTE . DTE . 6.2.4 ( ) . . DTE . a) DTE b) DTE c) DTE . DTE DCE , PSDN DTE PSDN ( X.32 ). X.32 ( ). DTEX 3511： 2006 6 DTE
16、PSDN . X.32 DTE DCE DTE DTE . 7. 7.1 (modulo 8) . (modulo 128) . 7.2 DTE to DTE DTE PSDN ISO 7776 A B . A B . PSDN A B X.25 . DTE DTE A B . 7.3 T1 5 . 1031 . , (hop) , (modulo 128) . 8. 8.1 ITU T X.223 ISO 8878 QOS . X.25 X.32 . 8.2 8.2.1 DTE DTE SNPA . X.25 ( ). NSAP . . 8.2.2 DTE DCE SNPA ( DTE PS
17、DN). X.25 ITU T X.223 ISO 8878 . 8.3 QOS 8.3.1 QOS NL . NS . 8.3.2 QOS NL . . (ITU T X.223 ISO 8878 ). 8.4 X 3511： 2006 7 . 1024 . 8.5 (ISO/IEC 8208 LIC, HIC, LTC, LOC HOC) . LTC HTC 1 . ISO/IEC 8208 . . 8.6 ISO/IEC 8208 (restart) . OSI X.25 153787 1 92 3(13) (02)26240114 (02)262401489 http:/ KSKSKSSKSKS KSKS SKS KSKS SKSKS KSKSKSKorean Agency for Technology and Standards http:/www.kats.go.kr KS X 3511： 2006 Information technologyUs e of X.25 packet layer protocol to provide the OSI connectionmode network service over the telephone network ICS 35.100.30
