1、ITU-T RECIN*ISOO (REVaL) 93 4862593 0582773 T77 m INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU INTEGRATED SERVICES DIGITAL NETWORK (ISDN) INTERNETWORK INTERFACES 1.500 (03/93) GENERAL STRUCTURE OF THE ISDN INTERWQR KING RECOMMENDATIONS ITU-T Recommendat
2、ion 1.500 (Previously “CCITT Recommendation”) ITU-T RECNN*I.SOO (REV*kL) 93 = LI862591 0582774 903 FOREWORD The IT Telecommunication Standardization Sector (IT-T) is a permanent organ of the International Telecom- munication Union. The IT-T is responsible for studying technical, operating and tariff
3、 questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Conference (WTSC), which meets every four years, established the topics for study by the ITU-T Study Groups which, in their turn, produce R
4、ecommendations on these topics. IT-T Recommendation 1.500 was revised by the ITU-T Study Group XWI (1988-1993) and was approved by the WTSC (Helsinki, March 1-12, 1993). NOTES 1 As a consequence of a reform process within the International Telecommunication Union (ITU), the CCIT ceased to exist as o
5、f 28 February 1993. In its place, the IT Telecommunication Standardization Sector (IT-T) was created as of 1 March 1993. Similarly, in this reform process, the CCIR and the IFRB have been replaced by the Radiocommunication Sector. In order not to delay publication of this Recommendation, no change h
6、as been made in the text to references containing the acronyms “CCITT, CCIR or IFRB” or their associated entities such as Plenary Assembly, Secretariat, etc. Future editions of this Recommendation will contain the proper terminology related to the new ITU structure. 2 telecommunication administratio
7、n and a recognized. operating agency. In this Recommendation, the expression “Administration” is used for conciseness to indicate both a O IT 1993 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopy
8、ing and microfilm, without permission in writing from the ITU. CONTENTS 1 Inuoduction . 2 Organization of ISDN interworking Recommendations 2.1 General level . : . 2.2 Scenario level . 2.3 Functional level 2.4 Protocol level 3 References . 3.1 Interworking . 3.2 Services and network capabilities 3.3
9、 Signalling . 3.4 Rate adaptation . 3.5 Numbering Recommendation 1.500 (03/93) Page 1 1 1 1 1 3 3 3 3 4 4 4 i ITU-T RECHN*I-SOO (REVS11 93 Y862591 058277b 786 Recommendation 1500 Figure 1 shows the organhation of the ISDN interworking Recommendations contained in the 1.500-Series Recommendations, an
10、d the relationship with other Recommendations. The Recommendations in Figure 1 have been grouped by level of detail into: I l - generalevel; I - scenario level; l - functional level; i I - protocol level. l GENERAL STRUCTURE OF THII ISDN INTERWORKING RECOMMENDATIONS I 2.1 General level (Melbourne, 1
11、988, amended at Helsinki, 1993) 1 Introduction An ISDN is a network, in general evolving from a telephony Integrated Digital Network, that provides end-to-end digital connectivity to support a wide range of services, including voice and non-voice services, to which users have access by a limited set
12、 of standard multi-purpose user network mterfaces. In contrast, existing dedicated networks have always been developed for specific (types of) services. Therefore, especially in the initiai phase, the ISDN may support many services which in principle are still existent in dedicated networks. Thus, i
13、t is necessary to provide interworking between ISDN and dedicated networks to allow communication between terminals belonging to equivalent services offered through different networks. There will be a need for interworking functions between ISDN and dedicated networks to cope with the different envi
14、ronments given by the various networks. The structure of these IWFs showing the functions necessary for the mapping should be uniform to permit, if possible, a common use of functional parts in several IWFs. Detailed description of these IWFs, which (as far as is possible), should permit conveyance
15、of ISDN fatures through existing networks, is given m the 1.500-Series of Recommendations. The 1.50O-Series of Recommendations deal with network aspects of interworking. 2 Organization of ISDN interworking Recommendations Recommendations 1.500 and 1.510 form the general level, i.e., the basis for Re
16、commendations in the scenario and functional levels. Recommendation 1.500 describes the orgauization of the (ISDN interworking) Recommendations and the structure of the 1.500-Series of Recommendations, whilst 1.510 sets out the ISDN interworking principles. 2.2 Scenario level The scenario level of R
17、ecommendations describes the general arrangements for interworking between ISDN and ISDN, and between ISDN and dedicated networks. Recommendation 1.515 speciSing the parameter exchange which may be necessary for interworking situations, is also located at the scenario level. 2.3 Functional level The
18、 detailed level is formed by those Recommendations that are speciSing the interworking functional requirements of the interworking scenarios shown in the scenario level Recommendations. Recommendation IS00 (03/93) 1 _ ITU-T RECMN*I=SOO (REV*L) 93 4Eb2593 0582777 bL2 W I r- I I I ,I _- I Il u _- 2 Re
19、commendation 1.500 (03/93) ITU-T RECMN*I-SOO (REVdL) 93 W 48b2591 0582778 559 W 2.4 Protocol level In the protocol lever, the protocols listed are those th& appear at the reference points K, and N,. NOTE - ISDN interworking related subjects that correspond to the above four levels are also dealt wit
20、h in the Recommendations 1.310,1.324,1.340, X.300 and X.301. Recommendation 1.310 defines the interworking reference points and an outline description of IWF. Recommendation 1.340 defines ISDN Connection Types. Recommendations X.300 and X.301 give the guiding principles and functions for interworkin
21、g between networks offering data services described in Recommendations X.l and X.10. 2.5 Recommendations which relate to interworking are shown in Figure 1 and are assigned to the levels listed in 2. As the contents of some Recommendations cover more than one level, these Recommendations appear at e
22、ach level to which they relate. 3 References The references are general to all 1.500 Recommendations and are to be read in conjunction with Figure 1, where the organization of ISDN interworking Recommendations is shown. 3.1 Interworking X.300-Series Interworking between public networks, and between
23、public networks and other networks for 1.3% ISDN architecture functional model the provision of data transmission services 1.340 X.3 1 X.81 Connection typedelements for ISDN-ISDN interworking Support of packet-mode terminal equipment by an ISDN Interworking between an ISDN circuit switched and a cir
24、cuit switched public data network (CSPDN) 3.2 Services and network capabilities x. 1 x.2 x.10 1.122 1.200-Series 1.3 10 1.320 1.325 1.411 1.4 12 1.420 1.421 International user classes of service in public data networks and integrated services digital networks (ISDNs) International data transmission
25、services and optional user facilities in public data networks and ISDNs Categories of access for data terminal equipment TE) to public data transmission services Framework for providing additional packet-mode bearer services Service aspects supported by an ISDN ISDN - Network functional principles I
26、SDN protocol reference model Reference confgurations for ISDN connection types ISDN user-network interfaces - Reference configurations ISDN user-network interfaces - Interface structures and access capabilities Basic rate user-network interface Primary rate user-network interface Recommendation 1.50
27、0 (03/93) 3 ITU-T RECNN*I.SOO (REV*1) 93 W Y862591 0582779 Y95 W 1.441 (Q.921) 1.451 (Q.931) ISDN user-network interface data link layer specification ISDN user-network interface layer 3 specification 3.3 Signalling Q.700-Series Network protocols (MTP, ISUP, etc.) Q. 120-4.180 Specification of Signa
28、lling Systems No. 4 and No. 5 Q.251-Q.300 Specification of Signalling System No. 6 Q.310-Q.490 Specification of Signalling Systems R1 and R2 X.25 Interface between data terminal equipment (DTE) and data circuit equipment CE) for terminals operating in the packet-mode and connected to public data net
29、works by dedicated circuits X.71 Decentralized terminal and transit control signalling system on international circuits between synchronous data networks Packet switched signalling system between public networks providing data transmission services x.75 u. 12 Terminal and transit control signalling
30、system for telex and similar services on international circuits (type D signalling) 3.4 Rate adaptation 1.460 1.461 (X.30) Multiplexing, rate adaptation and support of existing interfaces Support of X.21, X.21 bis and X.20 bis based DTEs by an ISDN 1.462 Support of packet-mode terminal equipment by
31、an ISDN G.31) 1.463 (v.110) 1.464 Support of DTEs with V-Series type interfaces by an ISDN Multiplexing, rate adaptation and support of existing interfaces for restricted 64 kbit/s transfer capability Support by ISDN of DTEs with V-Series type interfaces with provision for statistical 1.465 (v. 120)
32、 multiplexing 3.5 Numbering x. 121 x. 122 International numbering plan for public data networks Numbering plan interworking between a Packet Switched Public Data Network (PSPDN) and an Integrated Services Digital Network (ISDN) or Public Switched Telephone Network (PSTN) in the short-term Numbering
33、plan for the ISDN era Numbering plan interworking in the ISDN era ISDN numbering and addressing principles Numbering principles for interworking between ISDNs and dedicated networks with different numbering plans Plan for telex destination codes 1.331 (Fi.164) E.166 1.330 1.332 F.69 4 Recommendation 1.500 (03/93)
