1、INTERNATIONAL TELECOMMUNICATION UNION ITU=T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU X.213 (1012001) SERIES X: DATA NETWORKS AND OPEN SYSTEM COMMUNICATIONS Open Systems Interconnection - Service definitions Information technology - Open Systems Interconnection - Network service definition ITU
2、-T Recommendation X.213 (Formerly CCITT Recommendation) ITU-T X-SERIES RECOMMENDATIONS DATA NETWORKS AND OPEN SYSTEM COMMUNICATIONS PUBLIC DATA NETWORKS Services and facilities Interfaces Transmission, signalling and switching Network aspects Maintenance Administrative arrangements Model and notatio
3、n Connection-mode motocol specifications OPEN SYSTEMS INTERCONNECTION X.1-X.19 X.20-X.49 X.50-X.89 X.90-X.149 X.150-X.179 X. 180-X.199 X.200-X.209 X.220-X.229 Connectionless-mode protocol specifications PICS proformas Protocol Identification Security Protocols Layer Managed Objects Conformance testi
4、ng General Satellite data transmission systems IP-based networks MESSAGE HANDLING SYSTEMS DIRECTORY OS1 NETWORKING AND SYSTEM ASPECTS Networking Efficiency Quality of service Naming, Addressing and Registration Abstract Syntax Notation One (ASN. 1) Systems Management fiamework and architecture Manag
5、ement Communication Service and Protocol Structure of Management Information Management functions and ODMA functions NTERWORKING BETWEEN NETWORKS OS1 MANAGEMENT SECURITY OS1 APPLICATIONS Commitment, Concurrency and Recovery Transaction processing Remote operations OPEN DISTRIBUTED PROCESSING X.230-X
6、.239 X.240-X.259 X.260-X.269 X.270-X.279 X.280-X.289 X.290-X.299 X.300-X.349 X.350-X.369 x.370-x.399 X.400-X.499 X.500-X.599 X.600-X.629 X.640-X.649 X.650-X.679 X.680-X.699 X.630-X.639 X.700-X.709 X.710-X.7 19 X.720-X.729 x.730-x.799 X.800-X.849 X.850-X.859 X.860-X.879 X.880-X.899 X.900-X.999 For fu
7、rther details, please refer to the list of ITU-T Recommendations. INTERNATIONAL STANDARD ISO/IEC 8348 ITU-T RECOMMENDATION X.213 Information technology - Open Systems Interconnection - Network service definition Summary This Recommendation 1 International Standard defines the set of capabilities, in
8、 terms of abstract service definition, provided by the Network Layer to the Transport Layer. For designers of Transport Layer protocols, it provides a definition of the Network service to allow design and implementation independent of details of the Network Layer protocol. For designers of Network L
9、ayer protocols, it defines the set of capabilities to be made available through the action of the protocol. Source ITU-T Recommendation X.213 was prepared by ITU-T Study Group 7 (2001-2004) and approved on 29 October 2001. An identical text is also published as ISOAEC 8348. ITU-T Rec. X.213 (10/2001
10、) 1 FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions
11、and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on t
12、hese topics. The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some areas 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 ex
13、pression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Int
14、ellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, ITU had not rece
15、ived notice of intellectual property, protected by patents, which may be required to implement this Recommendation. 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 2002 All rights reserv
16、ed. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from ITU. 11 ITU-T Rec. X.213 (10/2001) CONTENTS SECTION 1 . GENERAL . 1 Scope 2 Normative references 2.1 2.2 Addit
17、ional references . 3 Definitions 3.1 Basic reference model definitions . 3.2 Service conventions definitions . 3.3 Network Service definitions 3.4 Network addressing defitions . 3.5 4 Abbreviations 5 Conventions 5.1 General conventions 5.2 Parameters . 5.3 Overview and general characteristics . Type
18、s and classes of Network Service Identical Recommendations 1 International Standards . Network layer architecture definitions NC end-point identification convention 6 7 SECTION 2 - DEFINITION OF THE CONNECTION-MODE SERVICE . 8 9 10 11 I l 12 13 14 Features ofthe connection-mode Network Service Model
19、 of the connection-mode Network Service . 9.1 9.2 Model ofa Network Connection . Quality of the connection-mode Network Service 10.1 Determination of QOS . 10.2 Definition of QOS-parameters . Sequence of primitives . 1 1.1 Relation of primitives at the two NC end-points . 11.2 Sequence of primitives
20、 at one NC end-point . 12.1 Function . 12.2 Types of primitives and parameters . 12.3 Sequence ofprimitives 13.1 Function . 13.2 13.3 13.4 13.5 Data transfer phase . 14.1 Data transfer 14.2 Receipt confirmation service . 14.3 Expedited data transfer service 14.4 Reset service Model ofthe connection-
21、mode Network Layer Service Connection establishment phase . Connection release phase Types of primitive and parameters Sequence of primitives when releasing an established NC . Sequence of primitives in an NS user rejection of an NC establishment attempt Sequence of primitives in an NS provider reje
22、ction of an NC establishment attempt . SECTION 3 . DEFINITION OF THE CONNECTIONLESS-MODE SERVICE Features of the connectionless-mode Network Service Model of the connectionless-mode Network Service . 16.1 Model of the connectionless-mode Network Layer Service 16.2 Model of a network connectionless-m
23、ode transmission 15 16 ITU-T Rec . X.213 (10/2001) Page 1 1 1 1 2 2 2 3 3 3 4 4 5 5 5 5 5 6 6 6 7 7 7 11 11 12 15 15 15 18 18 18 26 26 26 27 28 29 29 30 30 31 32 33 36 36 36 36 36 . 111 17 Quality of the connectionless-mode Network Service 17.1 Determination of QOS . 17.2 Definition of network conne
24、ctionless-mode QOS-parameters 17.3 Route selection considerations 18 Sequence of primitives . 19 Data transfer . 19.1 Function . 19.2 Types of primitives and parameters . 19.3 Sequence of primitives Annex A - Network Layer Addressing A.l General A.2 Scope . A.3 Concepts and terminology . A.4 Princip
25、les for creating the OS1 Network addressing scheme . AS Network address dennition A.6 Character based DSP allocation A.7 Reference publication formats . A.8 Network entity titles Annex B - Rationales for the material in Annex A . ID1 formats (see A.5.2.1.2) Reservation of AFI values 00-F and FF (see
26、 Table A.1) . Derivation ofthe preferred encodings (see A.5.3) . Annex C - Facilities for conveying service characteristics in the connectionless-mode Network Service . C.l Introduction . C.2 Function . C.3 Types of primitives and parameters . C.4 Service characteristics . C.5 Types of primitives an
27、d parameters . B.l B.2 B.3 Page 38 38 38 39 40 40 40 41 41 43 43 43 43 46 47 54 55 55 56 56 57 57 58 58 58 58 59 59 iv ITU-T Rec . X.213 (10/2001) Introduction This Recommendation I International Standard is one of a set of Recommendations and International Standards produced to facilitate the inter
28、connection of computer systems. It is related to other Recommendations and International Standards in the set as defined by the Reference Model of Open Systems Interconnection (OSI). The OS1 Reference Model (ITU-T Rec. X.200 1 ISOAEC 7498-1) subdivides the area of standardization for interconnection
29、 into a series of layers of specification, each of a manageable sue. This Recommendation I International Standard defines the Service provided by the Network Layer to the Transport Layer at the boundary between the Network and Transport Layers of the Reference Model. It provides for the designers of
30、 Transport protocols a definition of the Network Service existing to support the Transport protocol and for the designers of Network protocols a definition of the services to be made available through the action of the Network protocol over the underlying service. This relationship is illustrated in
31、 Figure O. Transport service Network service Transport protocol TIS0029062 u Figure O - Relationship of the Network Service to OS1 Network and Transport protocols The use of the word “Network“ to name the “Network“ Layer of the OS1 Reference Model should be distinguished fiom the use of the word “ne
32、twork“ to denote a communications network as conventionally understood. To facilitate this distinction, the term “subnetwork“ is used for a collection of physical equipment, commonly called a “network“ (see Rec. X.200 I ISO/IEC 7498-1). Subnetworks may be either public networks or privately supplied
33、 networks. In the case of public networks, their properties may be determined by separate Recommendations such as CCITT Rec. X.21 for a circuit-switched network or ITU-T Rec. X.25 for a packet-switched network. Throughout the set of OS1 Recommendations and international Standards the term “Service“
34、refers to the abstract capability provided by one layer of the OS1 Reference Model to the layer above it. Thus, the Network Service defined in this Recommendation 1 International Standard is a conceptual architectural Service, independent of administrative divisions. NOTE -It is important to disting
35、uish the specialized use of the term “Service“ within the set of OS1 Recommendations and International Standards fiom its use elsewhere to describe the provision of a service by an organization (such as the provision of a service, as defined in other Recommendations, by an Administration). Any parti
36、cular subnetwork may or may not support the OS1 Network Service. The OS1 Network Service may be provided by a combination of one or more subnetworks and optional additional functions between or outside these subnetworks. ITU-T Rec. X.213 (10/2001) V ISODEC 8348:2002 (E) INTERNATIONAL STANDARD ITU-T
37、RECOMMENDATION Information technology - Open Systems Interconnection - Network service definition SECTION 1 - GENERAL 1 Scope This Recommendation I International Standard defines the OS1 Network Service in terms of: a) b) c) the primitive actions and events of the Service; the parameters associated
38、with each primitive action and event, and the form which they take; the interrelationship between, and the valid sequences of, these actions and events. The principal objectives of this Recommendation I Intemational Standard are: 1) 2) 3) To spec the characteristics of a conceptual Network Service a
39、nd thus, supplement the Reference Model in guiding the development of Network Layer protocols. To encourage convergence of the capabilities offered by providers of subnetworks. To provide a basis for the individual enhancement of existing heterogeneous subnetworks to a common subnetwork-independent
40、Network Service to enable them to be concatenated for the purpose of providing global communication. (Such concatenation may involve optional additional functions which are not defined in this Recommendation I International Standard.) A definition of the quality of service is an important element of
41、 this Recommendation I International Standard. To provide a basis for the development and implementation of subnetwork-independent Transport Layer protocols decoupled fiom the variability of underlying public and private subnetworks and their specific interface requirements. This Recommendation I In
42、ternational Standard does not specify individual implementations or products nor does it constrain the implementation of entities and interfaces within a system. There is no conformance of equipment to this Recommendation I International Standard. Instead, conformance is achieved through implementat
43、ion of conforming OS1 Network protocols which fulfil the Network Service defined in this Recommendation I International Standard. 4) 2 Normative references The following Recommendations and International Standards contain provisions which, through reference in this text, constitute provisions of thi
44、s Recommendation I International Standard. At the time of publication, the editions indicated were valid. All Recommendations and Standards are subject to revision, and parties to agreements based on this Recommendation I International Standard are encouraged to investigate the possibility of applyi
45、ng the most recent edition of the Recommendations and Standards listed below. Members of the IEC and IS0 maintain registers of currently valid International Standards. The Telecommunication Standardization Bureau of the ITU maintains a list of currently valid ITU-T Recommendations. 2.1 Identical Rec
46、ommendations I International Standards - ITU-T Recommendation X.200 (1994) I ISOAEC 7498-1 :1994, Information technology - Open Systems Interconnection - Basic Reference Model: The Basic Model. ITU-T Recommendation X.210 (1993) I ISOAEC 1073 1: 1994, Information technology - Open Systems Interconnec
47、iion - Basic Reference Model: Conventions for the dejnition of OSI services. ITU-T Recommendation X.224 (1995) I ISOAEC 8073:1997, Information technology - Open Systems Interconnection - Protocol for providing the connection-mode transport service. - - IT-T Rec. X.213 (10/2001) 1 ISODEC 8348:2002 (E
48、) 2.2 Additional references - CCITT Recommendation E. 163 (1988), Numbering plan for the international telephone service. - ITU-T Recommendation E. 164 (1997), The international public telecommunication numberingplan. - ITU-T Recommendation E. 19 1 (2000), B-ISDN addressing. - ITU-T Recommendation E
49、.191.1 (2001), Criteria and procedures for the allocation of ITU-T International Network Designator Addresses. ITU-T Recommendation F.69 (1994), The international telex service - Service and operational provisions of telex destination codes and telex network identijcation codes. CCITT Recommendation T.50 (1 992), International Reference Alphabet (IRA) (Formerly International Alphabet No. 5 or IAS;) -Information technology - 7-bit coded character set for information interchange. ITU-T Recommendation X. 121 (2000), International numberingplan forpublic data networks. ITU-T Recommendation
