1、STD-ITU-T RECMN X.325-ENGL L77b = i.IBb257L Ob27758 777 INTERNATIONAL TELECOMMUNICATION UNION ITU=T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU X.325 (1 0196) SERIES X: DATA NETWORKS AND OPEN SYSTEM COM M U N I CAT I O N Interworking between networks - General General arrangements for interworki
2、ng between Packet Switched Public Data Networks (PSPDNs) and Integrated Services Digital Networks (ISDNs) for the provision of data transmission services ITU-T Recommendation X.325 (Previously CCITT Recommendation) ITU-T X-SERIES RECOMMENDATIONS DATA NETWORKS AND OPEN SYSTEM COMMUNICATION PUBLIC DAT
3、A NETWORKS Services and facilities Interfaces Transmission, signalling and switching Network aspects Maintenance Administrative arrangements Model and notation Service definitions Connection-mode protocol specifications Connectionless-mode protocol specifications PICS proformas Protocol Identificati
4、on Security Protocols Layer Managed Objects Conformance testing OPEN SYSTEM INTERCONNECTION INTERWORKING BETWEEN NETWORKS X.1-X.199 X. l-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.299 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.280
5、-X.289 X.290-X.299 X.3O-X.399 General x30-x349 Satellite data transmission systems MESSAGE HANDLING SYSTEMS DIRECTORY OS1 NETWORKING AND SYSTEM ASPECTS Networking Efficiency Naming, Addressing and Registration Abstract Syntax Notation One (ASN.l) Systems Management framework and architecture Managem
6、ent Communication Service and Protocol Structure of Management Information Management functions OS1 MANAGEMENT SECURITY OS1 APPLICATIONS Commitment, Concurrency and Recovery Transaction processing Remote operations OPEN DISTRIBUTED PROCESSING X.350-X.399 x.400-x.499 x.500-x.599 X.600-X.699 X.600-X.6
7、29 X.630-X.649 X.650-X.679 X.680-X.699 X.700-X.799 X.700-X.709 X.710-X.719 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. STD-ITU-T RECMN X-325-ENGL L97b 48b259L Ob277b0 325 FOREWORD
8、The ITU-T (Telecommunication Standardization Sector) is a permanent organ of the International Telecommunication Union (ITU). The ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommen- dations on them with a view to standardizing telecommunications on a wor
9、ldwide basis. The World Telecommunication Standardization 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 ITU-T is covered b
10、y the procedure laid down in WTSC Resolution No. 1 (Helsinki, March 1-12, 1993). ITU-T Recommendation X.325 was revised by ITU-T Study Group 7 (1993-1996) and was approved under the WTSC Resolution No. 1 procedure on the 5th of October 1996. NOTE In this Recommendation, the expression “Administratio
11、n” is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. O ITU 1997 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, wit
12、hout permission in writing from the IT. Recommendation X.325 (10/96) 1 1 2 3 4 5 6 7 11 STD-ITU-T RECMN X-325-ENGL L77b Vflb259L Ob277bL 2bL m CONTENTS Page Scope 1 References 1 Terms and definitions . 2 Abbreviations . 2 Conventions 2 General aspects . 3 6.1 PSPDN 3 6.2 ISDN . 3 6.3 Call control be
13、tween the PSPDN and ISDN . 3 6.4 Functionalities of the PSPDN and ISDN 3 Specific interworking arrangements . 7.1 Interworking between PSPDN and ISDN where a packet switched bearer is requested 7.1.1 7.1.2 7.1.3 7.1.4 7.1.5 7.1.6 7.1.7 7.1.8 Transfer of addressing information . Arrangements for faci
14、lities related to the QOS of the call Arrangements for facilities related to specific routing conditions applying to the call . Arrangements for facilities related to protection mechanisms requested by the user of a call . Arrangements for facilities to convey user data in addition to the normal dat
15、a flow in the data transfer phase . Arrangements for other facilities Arrangements for facilities related to charging conditions applying to the call Arrangements for internal network utilities (not visible for users) . Interworking between a PSPDN and ISDN where a circuit switched bearer is request
16、ed . 7.2 7.2.1 Interworking by call-control mapping 7.2.2 Intenvorking by port access Interworking between PSPDN and ISDN where a Ikame relaying bearer is requested 7.3.1 Interworking by call-control mapping 7.3.2 Interworking by port access 7.3 Recommendation X.325 (10/96) - 5 SUMMARY This Recommen
17、dation defines arrangements for the interworking between PSPDNs and ISDNs for the provision of data transmission services. These arrangements are applicable only to the interworking involving transmission capabilities, and not to interworking involving communication capabilities as described in Reco
18、mmendation X.300. INTRODUCTION This Recommendation is one of a set of Recommendations produced to facilitate considerations of interworking between networks. It is based on Recommendation X.300, which defines the general principles for interworking between public networks and other networks for the
19、provision of data transmission services. Recommendation X.300 indicates in particular how collections of physical equipment ca be represented as “subnetworks” for consideration in interworking situation. This Recommendation describes the interworking arrangements between ISDNs and PSPDNs for the pro
20、vision of data transmission services. . Recommendation X.325 (10/96) 111 STD-ITU-T RECMN X-325-ENGL L77b M L18b257L Ob277b3 034 M STDeITU-T RECMN X-325-ENGL L97b = 48b2591 0b277bll T70 Recommendation X.325 GENERAL ARRANGEMENTS FOR INTERWORKING BETWEEN PACKET SWITCHED PUBLIC DATA NETWORKS (PSPDNs) AN
21、D INTEGRATED SERVICES DIGITAL NETWORKS (ISDNs) FOR THE PROVISION OF DATA TRANSMISSION SERVICES (Melbourne, 1988; revised in 1996) 1 Scope The purpose of this Recommendation is to describe the general arrangements for the interworking between PSPDNs and ISDNs for the provision of data transmission se
22、rvices. These arrangements are applicable only to the interworking involving transmission capabilities, and not to interworking involving communication capabilities as described in Recommendation X.300. NOTE -The typing of subnetworks in this Recommendation is based on the support for the OS1 connec
23、tion-mode network service and is therefore only valid in this context. 2 References The following Recommendations and other references contain provisions which, through reference in this text, constitute provisions of this Recommendation. At the time of publication, the editions indicated were valid
24、. All Recommendations and other references are subject to revision; all users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendations and other references listed below. A list of the currently valid ITU-T Recommendatio
25、ns is regularly published. - - - CCITT Recommendation E.164 (1991), Numberingplan for the ISDN era. ITU-T Recommendation E.166X.122 (1996), Numberingplan interworking for the E.164 andX121. 1.230-Series Recommendations, Integrated services digital network - Service capabilities - Bearer services sup
26、ported by an ISDN. - 1.250-Series Recommendations, Integrated services digital network - Service capabilities - Supplementary services in ISDN. ITU-T Recommendation 1.500 (1993), General structure of the ISDN interworking Recommendations. ITU-T Recommendation X. 1 (1996), International user classes
27、of service in, and categories of access to, public data networks and Integrated Services Digital Networks (ISDNs). ITU-T Recommendation X.2 (1996), International data transmission services and optional user facilities in public data networks and ISDNs. ITU-T Recommendation X.10 (1993), Categories of
28、 access for Data Terminal Equipment (DTE) to public data transmission services. ITU-T Recommendation X.3 I (1 9959, Support ofpacket mode terminal equipment by an ISDN. ITU-T Recommendation X.33 (1996), Access to packet switched data transmission services via fiame reIaying data transmission service
29、s. ITU-T Recommendation X.75 (1 996), Packet-switched signalling system between public networks providing data transmission services. ITU-T Recommendation X.76 ( 1995), Network-to-network interface between public data networks providing the fiame relay data transmission service. ITU-T Recommendation
30、 X.12 1 (1996), International numbering plan for public data networks. ITU-T Recommendation X.300 (1996), General principles for interworking between public networks and between public networks and other networks for the provision of data transmission services. - - - - - - - - - - Recommendation X.3
31、25 (10/96) 1 - STD-ITU-T RECMN X.325-ENGL 277b E LiBb259L Ob277b5 907 E - ITU-T Recommendation X.301 (1996), Description of the general arrangements for call control within a subnetwork and between subnetworks for the provision of data transmission services. CCITT Recommendation X.302 (1988), Descri
32、ption of the general arrangements for internal network utilities within a subnetwork and intermediate utilities between subnetworks for the provision of data transmission services. CCITT Recommendation X.305 (1988), Functionalities of subnetworks relating to the support of OSI connection-mode networ
33、k services. ITU-T Recommendation X.321 (1996), General arrangements for interworking between Circuit Switched Public Data Networks (CSPDNs) and Integrated Services Digital Networks (ISDNs) for the provision of data transmission services. - - - 3 Terms and definitions This Recommendation makes use of
34、 the following terms defined in Recommendation X.300: a) transmission capability; b) communication capability; c) subnetwork functionality; d) data transmission service; e) interworking by call-control mapping; f) interworking by port access. This Recommendation makes use of following terms defined
35、in the 1.230-Series Recommendations: a) circuit switched bearer service; b) c) frame relaying bearer service. packet switched virtual circuit bearer service; 4 Abbreviations For the purposes of this Recommendation, the following abbreviations apply: CNIC CUG CUG/OA DTE ISDN IWF MSS PSPDN SS No. 7 TA
36、 TE TNIC Clearing Network Identification Code Closed User Group Closed User Group with Outgoing Access Data Terminal Equipment Integrated Services Digital Network Interworking function Mobile Satellite System Packet Switched Public Data Network Signalling System No. 7 Terminal Adaptor Terminal Equip
37、ment Transit Network Identification Code 5 Conventions No particular conventions are used. 2 Recommendation X.325 (10/96) STD-ITU-T RECMN X-325-ENGL L99b 48b259L Ob277bb q3 m 6 General aspects This Recommendation, in describing interworking arrangements between two subnetworks for the provision of d
38、ata transmission services, adheres to the general principles of Recommendation X.300. The environments of these two subnetworks are described in the following subclauses. See also Table 1. 6.1 PSPDN The PSPDN provides packet switched data transmission services as defined in Recommendations X.l and X
39、.2 for the provision of data transmission services, the PSPDN may be accessed by DTEs by the categories of access C and D as in Recommendation X. 1. In addition, the PSPDN may also be accessed via other networks, Le. PSTN (X. 1 categories L, P), CSPDN (X.1, categories K, O), PSPDN (Recommendation X.
40、75), MSS (Recommendation X.75), or ISDN (this Recommendation and X.l category Q). Private networks access the PSPDN via X.l, category of access D. 6.2 ISDN The ISDN may provide packet switched and/or circuit switched and/or frame relaying data transmission servicesbearer services as defined in Recom
41、mendations X.l, I.230-Series, and X.2. NOTE 1 - Supplementary services/optional user facilities for the circuit-mode operation on ISDN are in the 1.250-Series Recommendations. Recommendation X.2 applies to ISDN packet switched data transmission serviceshearer services. Supplementary services/optiona
42、l user facilities for the frame relaying operation on ISDN are for further study. For the provision of data transmission services, the ISDN may be accessed by DTEsTEs by the categories of access S, T, U, as defined in Recommendation X.l and/or the access methods defined in the 1.230-Series Recommend
43、ations. In addition, the ISDN may also be accessed via other networks, i.e. PSTN (see Recommendation I.530), CSPDN (Recommendation X. 1, category B and Recommendation X.321), PSPDN (this Recommendation), MSS (see Recommendation X.324), FRPDN (see Recommendation X.328), or ISDN (SS No. 7, Recommendat
44、ions X.75 and X.l, category Y). NOTE 2 - In the context of this Recommendation, and for purpose of provision of data transmission services only, the following categories of bearer services defined in the 1.230-Series Recommendations are considered (others are for further study): a) circuit-mode 64 k
45、bits unrestricted, 8 kHz structured; b) circuit-mode 64 kbits, 8 kHz structured, usable for speech information transfer; c) circuit-mode 64 kbits, 8 kHz structured, usable for 3.1 kHz audio information transfer; d) virtual call and permanent virtual circuit; e) frame-relaying bearer service. 6.3 Cal
46、l control between the PSPDN and ISDN The general arrangements for call control between PSPDN and ISDN are as defined in Recommendation X.301. Network utilities used between the PSPDN and ISDN are as defined in Recommendation X.302 (not visible for users). Supplementary servicesoptional user faciliti
47、es for the circuit-mode operation on ISDN are in the 1.250-Series Recommendations. NOTE - Supplementary services/optional user facilities for the frame relaying operation on ISDN are for further study. 6.4 Functionalities of the PSPDN and ISDN The functionalities of different types of subnetworks ar
48、e described in Recommendation X.305. In the case where the ISDN is used to provide a circuit switched or frame relaying data transmission servicehearer service, the functionality of the PSPDN and ISDN differ. Therefore, in order to enable interworking, procedures must be operated over the circuit sw
49、itched or frame relaying bearer on the ISDN to achieve functional compatibility. In the case where the ISDN is used to provide a packet switched data transmission servicehearer service, the PSPDN and ISDN are functionally compatible. Recommendation X.325 (10196) 3 7 Specific interworking arrangements As described in Recommendation X.300, the following interworking cases should be distinguished: a) b) interworking between PSPDN and ISDN where a packet mode bearer is used; interworking between PSPDN and ISDN where a circuit mode bearer is used 1) interworking
