1、INTERNATIONAL TELECOMMUN CATI ON UN ION ITU-T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU X.227 Amendment 2 (08/97) SERIES X: DATA NETWORKS AND OPEN SYSTEM COM M U N I CATI ON Open System Interconnection - Connection-mode protocol specifications Information technology - Open Systems Interconnect
2、ion - Connection-oriented protocol for the association control service element: Protocol specification Amendment 2: Fast-associate mechanism ITU-T Recommendation X.227 - Amendment 2 (Previously CCITT Recommendation) ITU-T X-SERIES RECOMMENDATIONS DATA NETWORKS AND OPEN SYSTEM COMMUNICATION PUBLIC DA
3、TA NETWORKS Services and facilities Interfaces Transmission, signalling and switching Network aspects Maintenance Administrative arrangements OPEN SYSTEM INTERCONNECTION Model and notation X.1-X.199 X.1-X. 19 X.20-X.49 X SO-X. 89 X.90-X. 149 X. 150-X. 179 X.180-X. 199 X.200-X.299 X.200-X.209 Service
4、 definitions X.21 O-X.219 Connectionless-mode protocol specifications PICS proformas Protocol Identification Security Protocols Layer Managed Objects Conformance testing INTERWORKING BETWEEN NETWORKS General Satellite data transmission systems MESSAGE HANDLING SYSTEMS DIRECTORY OS1 NETWORKING AND SY
5、STEM ASPECTS Networking Efficiency Naming, Addressing and Registration Abstract Syntax Notation One (ASN.1) Systems Management framework and architecture Management Communication Service and Protocol Structure of Management Information Management functions OS1 MANAGEMENT SECURITY OS1 APPLICATIONS Co
6、mmitment, Concurrency and Recovery Transaction processing Remote operations OPEN DISTRIBUTED PROCESSING X.230-X.239 X.240-X.25 9 X.260-X.269 X.270-X.279 X.280-X.289 X.290-X.299 X.300-X.399 X.3OO-X.349 X.350-X.399 X .400-X ,499 X.500-X.599 X.600-X. 699 X.600-X.629 X.630-X.649 X.650-X.679 X.680-X.699
7、X .700-X . 799 X ,700-X . 709 X.7 1 0-X.7 1 9 X.720-X.729 X.730-X.799 X.800-X.849 X.850-X.899 X.850-X.859 X.860-X.879 X ,880-X. 899 X.900-X.999 For further details, please refer to ITU-T List of Recommendations. INTERNATIONAL STANDARD 8650-1 ITU-T RECOMMENDATION X.227 INFORMATION TECHNOLOGY - OPEN S
8、YSTEMS INTERCONNECTION - CONNECTION-ORIENTED PROTOCOL FOR THE ASSOCIATION CONTROL SERVICE ELEMENT: PROTOCOL SPECIFICATION AMENDMENT 2 Fast-associate mechanism Summary The fast-associate mechanism allows a session connection, including its embedded presentation connection and application association,
9、 to be established using a compressed form of the information that would otherwise be sent on the S-CONNECT exchange. The compressed form, called the upper-layer context identifier, is a reference to an upper-layer context specification, which is a definition of the fields of the application ACSE, p
10、resentation and session protocols that would be sent on the full-form connect messages. The upper-layer context identifier may be parameterized to include values for variable fields allowed by the full form protocols for the upper-layers. Within the ACSE protocol, the addition is the definition of t
11、he construction of the User-summary parameter of the P-CONNECT primitives from the semantics of the AARQ fields and the User-summary parameter of the corresponding A-ASSOCIATE primitive. Source The IT-T Recommendation X.227, Amendment 2 was approved on the 9th of August 1997. The identical text is a
12、lso published as ISO/IEC International Standard 8650-1. ITU-T Rec. X.227 (1995)/Amd.2 (1997 E) i - STD-ITU-T RECMN X-227 AMD 2-ENGL 1997 = 48b2571 Ob43bl19 283 FOREWORD ITU (International Telecommunication Union) is the United Nations Specialized Agency in the field of telecommuni- cations. The ITU
13、Telecommunication Standardization Sector (IT-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 Stand
14、ardization Conference (WTSC), which meets every four years, establishes the topics for study by the IT-T Study Groups which, in their turn, 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.
15、 1. . In some areas of information technology which fall within IT-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
16、a recognized operating 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
17、 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, the ITU had not received notice of intellectual property, protected by patents, which may be required to implement
18、 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 1998 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, ele
19、ctronic or mechanical, including photocopying and microfilm, without permission in writing from the IT. 11 ITU-T Rec. X.227 (1995)/Amd.2 (1997 E) - - CONTENTS Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
20、. . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Subclause 2.1 Subclause 6.3 . . . . New subclause 6.4 bis Subclause 7.1.3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
21、. . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Subclause 7.1.3.1 . Subclause 7.1.3.2 . Subclause 7.1.3.3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . _. . . . . . . . . . . . . . . . . . . , . . . . . . . . .
22、 . . . . . ._ . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . Subclause 7.1.3.4 . Subclause 8.1.2 Subclause 8.1.3 . . . . I. Clause 12 Page 1 1 1 1 2 ITU-T Rec. X.227 (1995)/Amd.2 (1997 E) . 111 ISODEC 8650-1 : 1996/Amd.2 : 1998 (E) INTERNATIONAL STANDARD ITU-
23、T RECOMMENDATION INFORMATION TECHNOLOGY - OPEN SYSTEMS INTERCONNECTION - CONNECTION-ORIENTED PROTOCOL FOR THE ASSOCIATION CONTROL SERVICE ELEMENT: PROTOCOL SPECIFICATION AMENDMENT 2 Fast-associate mechanism . 1) Introduction Add the following paragraphs: The fast-associate mechanism allows a session
24、 connection, including its embedded presentation connection and application association, to be established using a compressed form of the information that would otherwise be sent on the S-CONNECT exchange. The compressed form, called the upper-layer context identifier, is a reference to an upper- la
25、yer context specification, which is a definition of the fields of the application ACSE, presentation and session protocols that would be sent on the full-form connect messages. The upper-layer context identifier may be parameterized to include values for variable fields allowed by the full form prot
26、ocols for the upper-layers. Within the ACSE protocol, the addition is the definition of the construction of the User-summary parameter of the P-CONNECT primitives from the semantics of the AARQ fields and the User-summary parameter of the corresponding A-AS SOCIATE primitive. 2) Subclause 2.1 Insert
27、 the following references by numerical order: - IT-T Rec. X.216 (1994)/Amd.l (1997) I ISO/IEC 8822:1994/Amd.l:1998, Information technology - Open Systems Interconnection - Presentation service definition - Amendment 1: EfJiciency enhancements. ITU-T Rec. X.217 (1995)/Amd.2 (1997) 1 ISO/IEC 8649:1996
28、/Amd.2:1998, Information technology - Open Systems Interconnection - Service definition for the association control service element - Amendment 2: Fast-associate mechanism. - 3) Subclause 6.3 In Table 2, add User Summary to the list ofparameters for A-ASSOCIATE request ajer User Information. 4) New
29、subclause 6.4 bis Add a new subclause afier 6.4: 6.4 bis User summary mechanism If the fast-associate mechanism is used during association establishment, the initiating ACPM as well as forming an AARQ APDU to be passed to the Presentation service-provider in the User-Data parameter of a P-CONNECT re
30、quest, also passes the semantic content of the AARQ in the User Summary parameter of the P-CONNECT request. The User ITU-T Rec. X.227 (1995)/Amd.2 (1997 E) 1 ISOIEC 8650-1 : 1996/Amd.2 : 1998 (E) Summary parameter references an Upper-Layer Context specification and is a purely abstract parameter. If
31、 the A-ASSOCUTE request User Information parameter was present, the semantic content of this will have been supplied to the ACPM in the User Summary parameter of the A-ASSOCIATE request, and is conceptually included in the User Summary parameter of the P-CONNECT request. If the Presentation provider
32、 (via the Session service and protocol) makes use of the fast-associate mechanism, the responding ACPM will receive only the User Summary parameter on the P-CONNECT indication, and not the User-Data. The responding implementation will reconstruct the semantic content of the AARQ that would have been
33、 present in the P-CONNECT User-Data, and issue an A-ASSOCIATE indication with a User Summary parameter in place of its User-Data. Similarly, the responding ACPM will form a User Summary parameter on the P-CONNECT response from the AARE APDU, including the semantic content of the User Summary paramet
34、er of the A-ASSOCIATE response (if present) by reference to the same Upper-Layer Context specification. The initiating ACPM reconstructs the AARE. NOTE -The passing of the User Summary parameters and reconstruction of the ACSE APDUs from the Presentation User Summary parameters is abstract. There is
35、 no requirement for a real implementation to perform these actions. 5) Subclause 7.1.3 Addin b): . . . User-Data or a User Summary parameter on a P-CONNECT . Add at the end of d): or have a User Summary parameter) 6) Subclause 7.1.3.1 Add after the first paragraph: If the fast-associate mechanism is
36、 supported, the requesting ACPM identifies the semantic content of the AARQ, including the User-Data, in the User Summary parameter of the P-CONNECT request. 7) Subclause 7.1.3.2 Add at the end of thefirst paragraph: or reconstructs an AARQ APDU from the User Summary parameter of the P-CONNECT indic
37、ation primitive. 8) Subclause 7.1.3.3 Add after the first paragraph: If the fast-associate mechanism is supported, the accepting ACPM identifies the semantic content of the AARE, including the User-Data, in the User Summary parameter of the P-CONNECT response, by reference to the Upper-Layer Context
38、 specification identified by the User Summary parameter of the received P-CONNECT indication. 9) Subclause 7.1.3.4 Replace the second sentence of the second paragraph with the following: Either the User-Data parameter contains an AARE APDU or the User Summary parameter is a value from which the requ
39、esting ACPM can reconstruct the AARE APDU. 2 ITU-T Rec. X.227 (1995)/Amd.2 (1997 E) - - STD.ITU-T RECMN X.227 AMD 2-ENGL 1777 4Ab257L 0643b23 704 ISOflEC 8650-1 : 1996lAmd.2 : 1998 (E) 10) Subclause 8.1.2 Add the following new subclause after 8.1.2.2: 8.1.2.3 User Summary The User Summary parameter,
40、 if used, summarizes the semantic content of the AARQ by reference to an Upper-Layer Context specification. 11) Subclause 8.1.3 Add the following new subclause after 8.1.3.2: 8.1.3.3 User Summary The User Summary parameter, if used, summarizes the semantic content of the AARQ by reference to the sam
41、e Upper-Layer Context specification as was used in the User Summary parameter of the P-CONNECT request and indication. . 12) Clause 12 Change three to four infirst paragraph and add - Upper-Layer Context specifications to the list. Consequent), change the period at the end of the last item of the li
42、st, to a semi-colon. Add a new subclause 12.4, at the end of the 2ndparagraph of 12.3: 12.4 Upper-layer context specifications An upper-layer context Specification is a definition of all the field values that are required to format the hll-form ACSE, presentation and session establishment PDUs for a
43、 given application context and a given peer presentation address. NOTE - In practice, it is expected that an upper-layer context specification will be parameterized to allow for values which may be expected to be different for each establishment exchange between two peers (e.g. ACSE user information
44、), or for the same application between different peers (e.g. addressing information). An upper-layer context specification may be specified as part of an ITU-T Recommendation 1 International Standard. An upper-layer context specification may also be specified outside of ITU-T Recommendations I Inter
45、national Standards. In this situation, ISO/IEC 9834-1 specifies the procedures to register such an upper-layer context specification. ITU-T Rec. X.227 (1995)/Amd.2 (1997 E) 3 - STD.ITU-T RECMN X-227 AND 2-ENGL 2977 m 48b257L Ob43b24 b4U Series A Series B Series C Series D Series E Series F Series G
46、Series H Series I Series J Series K Series L Series M Series N Series O Series P Series Q Series R Series S Series T Series U Series V Series X Series Z ITU-T RECOMMENDATIONS SERIES Organization of the work of the ITU-T Means of expression: definitions, symbols, classification General telecommunicat
47、ion statistics General tariff principles Overall network operation, telephone service, service operation an( Non-telephone telecommunication services Transmission systems and media, digital systems and networks Audiovisual and multimedia systems Integrated services digital network human factors Tran
48、smission of television, sound programme and other multimedia signals Protection against interference Construction, installation and protection of cables and other elements of outside plant TMN and network maintenance: international transmission systems, telephone circuits, telegraphy, facsimile and
49、leased circuits Maintenance: international sound programme and television transmission circuits Specifications of measuring equipment Telephone transmission quality, telephone installations, local line networks Switching and signalling Telegraph transmission Telegraph services terminal equipment Terminals for telematic services Telegraph switching Data communication over the telephone network Data networks and open system communication Programming languages
