1、 STDoITU-T RECMN XOZ-ENGL 2000 II 48b2571 Ob74513 576 INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOM M U N I CATI ON STANDARDIZATION SECTOR OF ITU x.2 (0312000) SERIES X: DATA NETWORKS AND OPEN SYSTEM COMMUN I CAT I O NS Public data networks - Services and facilities International data transmis
2、sion services and optional user facilities in public data networks and ISDNs ITU-T Recommendation X.2 (Previously CCITT Recommendation) STD-ITU-T RECMN X-2-ENGL ZOO0 W 48b2591 Ob74514 402 ITU-T X-SERIES RECOMMENDATIONS DATA NETWORKS AND OPEN SYSTEM COMMUNICATIONS 1- PUBLIC DATA NETWORKS I Seniees an
3、d facilities x.1-x.19 Interfaces Transmission, signalling and switching Network aspects Maintenance Administrative arrangements OPEN SYSTEMS INTERCONNECTION Model and notation Service definitions Connection-mode protocol specifications Connectionless-mode protocol specifications PICS proformas Proto
4、col Identification Security Protocols Layer Managed Objects Conformance testing INTERWORKING BETWEEN NETWORKS General Satellite data transmission systems MESSAGE HANDLING SYSTEMS DIRECTORY OS1 NETWORKING AND SYSTEM ASPECTS Networking Efficiency X.20-X.49 X.50-X.89 X.90-X.149 X.150-X.179 X. 180-X. 19
5、9 X.200-X.209 X.210-X.219 X.220-X.229 X.230-X.239 X.240-X.259 X.260-X.269 X.270-X.279 X. 2 80-X. 289 X.290-X.299 X.300-X.349 X.350-X.399 X.400-X.499 X. 500-X.599 X. 600-X. 629 X. 63 O-X. 63 9 Quality of service X.640-X.649 Naming, Addressing and Registration X.650-X.679 Abstract Syntax Notation One
6、(ASN. 1) X.680-X.699 OS1 MANAGEMENT Systems Management framework and architecture X.700-X.709 Management Communication Service and Protocol X.710-X.719 Structure of Management Information X.720-X.729 Management functions and ODMA functions X.730-X.799 SECURITY X.800-X.849 OS1 APPLICATIONS Commitment
7、, Concurrency and Recovery X.850-X.859 Transaction processing X.860-X.879 Remote operations X.880-X.899 X. 900-X. 9 9 9 OPEN DISTRIBUTED PROCESSING I For further details, please refer to ITU-T List of Recommendaiions. STD-ITU-T RECMN X.2-ENGL 2000 W 48b259L Ob74515 349 m ITU-T RECOMMENDATION X.2 INT
8、ERNATIONAL DATA TRANSMISSION SERVICES AND OPTIONAL USER FACILITIES IN PUBLIC DATA NETWORKS AND ISDNs Summary This Recommendation describes international data transmission services (leased circuit, circuit switched, packet switched, and fiame relay) and optional user facilities in public data network
9、s and ISDNs. This revision includes optional user facilities for priority and service classes aspects of frame relay data transmission service. The revision also takes into account the addressing aspects connected with the using of E.164 Escape Code “O“. Source ITU-T Recommendation X.2 was revised b
10、y ITU-T Study Group 7 (1997-2000) and was approved under the WTSC Resolution No. 1 procedure on 3 1 March 2000. Recommendation X.2 (03/2000) 1 FOREWORD ITU (International Telecommunication Union) is the United Nations Specialized Agency in the field of telecommuni- cations. The ITU Telecommunication
11、 Standardization Sector (ITU-T) is a permanent organ of the ITU. The ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Confe
12、rence (WTSC), which meets every four years, establishes the topics for study by the ITU-T Study Groups which, in their tm, produce Recommendations on these topics. The approval of Recommendations by the Members of the IT-T is covered by the procedure laid down in WTSC Resolution No. 1. In some areas
13、 of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with IS0 and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized opera
14、ting agency. INTELLECTUAL PROPERTY RIGHTS The ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. The ITU takes no position concerning the evidence, validity or applicability of claimed Intell
15、ectual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, the ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendati
16、on. However, implementors are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database. O ITU 2000 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechani
17、cal, including photocopying and microfilm, without permission in writing from the ITU. 11 Recommendation X.2 (03/2000) - STD.ITU-T RECMN XuZ-ENGL 2000 W +862591i Ob74517 LI1 W CONTENTS 1 Introduction 2 Circuit witched data transmission service 3 Packet switched data transmission services 3.1 Direct
18、access to a packet switched data transmission service . 3.2 Port access to a packet switched data transmission service (user classes of service 20-26 and 29) 3.3 Port access to a packet switched data transmission service (user classes of service 8.12. 26 and 30) 3.4 Frame relay data transmission ser
19、vice . 4.1 Direct access to a flame relay data transmission service 4.2 5 Leased circuit data transmission service Appendix I - Coding of optional user facilities Appendix II - Relationship of ISDN (1.250-Series Recommendations) Supplementary SeMces and X.2 Optional User Facilites II . 1 Introductio
20、n . 11.2 Independent operation 11.3 Minimum relationship 11.4 Maximum relationship . 11.5 Summary . Additional capabilities provided by multicast service 4 Port access to a fiame relay data transmission service . Recommendation X.2 (03/2000) Page 2 2 2 2 6 8 9 12 12 12 12 14 17 17 17 18 18 20 . 111
21、STD-ITU-T RECMN X-Z-ENGL 2000 48b2591 Ob74518 O58 = Recommendation X2 INTERNATIONAL DATA TRANSMISSION SERVICES AND OPTIONAL USER FACILITIES IN PUBLIC DATA NETWORKS AND ISDNs (Geneva, 1972; amended at Geneva, 1976 and 1980; Malaga-Torremolinos, 1984; Melbourne, 1988 and Helsinki, 1993; revised in Gen
22、eva, 1996 and 2000) The ITU-T, considering a) the international user classes of service and categories of access defined in Recommendation X. 1 ; b) networks and ISDNs, which should be made available on an international basis; the need to standardize data transmission services, optional user facilit
23、ies and DTE services, in public data c) Administrations and which may be available on an international basis; the need to standardize additional optional user facilities and DTE services which may be provided by d) that the optional user facilities indicated in this Recommendation are defined in oth
24、er Recommendations, for example Recommendation X.30 1 for network implementations, where appropriate, and Recommendations X.2 1, X.25, etc. for network procedures; NOTE - Alignment and interworking between the facilities in this Recommendation and supplementary services in the 1.250-Series Recommend
25、ations are described in Appendix II. 4 the need to standardize the identification methods applicable to these DTE services, which identification methods should be made available on an international basis, and which identification methods may be provided by Administrations and may be available on an
26、international basis; f) the impact which these optional user facilities and DTE services could have on tariff structures, unanimously declares 1) Recommendation X. 1 for each of the following: that the optional user facilities should be standardized for each of the user classes of service indicated
27、in i) circuit switched data transmission services; ii) packet switched data transmission services; iii) leased circuit data transmission services; iv) fiame relay data transmission services; 2) that the optional user facilities to be made available on an international basis are indicated in the foll
28、owing clauses. Some of the optional user facilities are available on a per-call basis and others may be assigned for an agreed contractual period. In all cases, the user has the option of requesting a given optional user facility; 3) that the DTE services and the relative identification methods used
29、 when the packet switched data transmission service is obtained via a Public Switched Telephone Network (PSTN), a Circuit Switched Public Data Network (CSPDN), an Integrated Services Digital Network (ISDN) and a PDN providing fiame relay data transmission service should also be standardized and are
30、indicated in the following clauses. Recommendation X.2 (03/2000) 1 STD-ITU-T RECMN XOZ-ENGL ZOO0 48b2593 Ob74539 T94 D 1 Introduction 1.1 Optional user facility: Is a facility which complements the basic data transmission service defined in Recommendation X.l and based on the basic user facility(ies
31、). Consequently, it cannot be offered to a user as stand- alone service. It must be offered together or in association with a basic user facility. An optional user facility may be applicable to a number of data transmission services. This Recommendation indicates the degree of support required for t
32、he capabilities associated with the data transmission services. In general, this degree of support can be expressed as one of the following: E. An Essential user or DTE service or facility to be made available internationally. A An Additional user or DTE service or facility which may be available in
33、 certain data networks and may also be available internationally. FS: This item is for Further Study as to whether it will be supported at all in conjunction with one of the data transmission services. -: This item is not applicable. In certain cases, the degree of support depends on the support of
34、other services or facilities, or other aspects. This is indicated by adopting the following additional notation: Cn: Refers to a “conditional statement of support“ given below the table in which Cn appears. M: Support for the user or DTE service or facility is Mandatory by an Administration but it m
35、ay not be available internationally. Definitions of particular optional user facilities are contained in Recommendation X.7. 2 Circuit switched data transmission service Table 1 indicates the optional user facilities which should be made available on an international basis in the circuit switched da
36、ta transmission service provided by a CSPDN and those facilities which may be available in certain data networks and may also be available internationally. 3 Packet switched data transmission services 3.1 Direct access to a packet switched data transmission service Tables 2 and 3 indicate the servic
37、es and the optional user facilities, respectively, which should be made available on an international basis in the packet switched data transmission service, and those which may be available on certain data networks and may also be available internationally in case of a direct access to a packet swi
38、tched data transmission service. These services and optional user facilities are described in Recommendation X.25. A DTE may make use of one or more of these services and facilities. Some of optional user facilities in multicast service have another role (see Table 8). It should be noted that Recomm
39、endation X.25 has inherent features (e.g. the conveying of an address extension), which can be used end-to-end by users for providing an OS1 network service (see Recommendations X.213 and X.223). Such features are described in Recommendation X.25 and are so-called “ITU-T defined DTE facilities“ (see
40、 Annex GX.25). NOTE - The study of “connectionless services“ is for further study. 2 Recommendation X.2 (03/2000) STD-ITU-T RECMN X.2-ENGL i000 48b2573 Ob74520 ?Oh m Table 1K.2 - Optional user facilities in circuit switched data transmission service provided by a CSPDN ROA Recognized Operating Agenc
41、y (previously “recognized private operating agency“) NOTE - This optional user facility also provides the user with the capability to request the establishment of a point-to-multipoint configuration amongst the following: centralized multipoint, decentralized multipoint, broadcasting multipoint. Opt
42、ionai user facility .1 .2 .3 .4 .5 .6 .7 . .8 I .9 1.10 L.ll 1.12 1.13 1.14 1.15 1.16 1.17 1.18 1.19 1.20 2 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 Optional user facilities assigned for an agre.ed contractual period Direct call Closed user group Closed USeT group with outgoing access Closed user group w
43、ith incoming access incoming calls barred within a closed user group Outgoing calls barred within a closed user group Calling lie identification incoming calls barred Outgoing calls barred Bilateral closed user group Bilateral closed user group with outgoing access Reverse charging acceptance Connec
44、t when fiee Waiting allowed Call redirection On-line facility registration DTE inactive registratiodcancellation Date and time indication Hunt group Manual answer Optional mer facilities requested by the DTE on a per-call basis Direct call Abbreviated address calling Multi-address calling (Note) Rev
45、erse charging ROA selection Charag information Called line identification Closed user group selection Bilateral closed user PIOUD selection All user classes of service A E A A A A A A A A A A A A A A A A A A A A A A A A A E A Recommendation X.2 (0312000) 3 STD-ITU-T RECMN X.2-ENGL 2000 48b2591 Ob745
46、21 b42 Type of Service Viruai call service Table 2B.2 - Services in packet switched data transmission service (direct access) provided by a PSPDN User classes of service 8-11,26 20-26 29 (synchronous (start-stop mode), mode) 30-61 E E E Permanent virtual circuit service I E(Note) I FS FS NOTE - This
47、 service continues to be allocated an “El classification. However, while some Administrations continue to believe that the offering of this service is an essential feature of the international service, other Administrations have expressed the view that they will not offer the service internationally
48、. The international application depends on bilateral agreement. This service may not be available for the maritime mobile services. I Table 3K.2 - Facilities of packet switched data transmission service (direct access) provided by a PSPDN _ Optional user facility 1 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.
49、9 1.10 1.11 1.12 1.13 1.14 1.15 1.16 1.17 1.18 1.19 1.20 Optional user facilities assigned for an agreed contractual period Extended fiame sequence numbering (modulo 128) Super-extended fiame sequence numbering (modulo 32768) Multilink procedure Extended packet sequence numbering (modulo 128) Super extended packet sequence numbering (modulo 32768) D-bit modification Packet retransmission Incoming calls barred Outgoing calls barred One-way logical channel outgoing One-way logical channel incoming Non-standard default packet sizes (16,32,64,256, 512,1024,2048,4096) N
