1、 INTERNATIONAL TELECOMMUNICATION UNION ITU-T Q.2150.3TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (12/2002) SERIES Q: SWITCHING AND SIGNALLING Broadband ISDN Signalling ATM adaptation layer (SAAL) Signalling transport converter on SCTP ITU-T Recommendation Q.2150.3 ITU-T Q-SERIES RECOMMENDATIONS
2、SWITCHING AND SIGNALLING SIGNALLING IN THE INTERNATIONAL MANUAL SERVICE Q.1Q.3 INTERNATIONAL AUTOMATIC AND SEMI-AUTOMATIC WORKING Q.4Q.59 FUNCTIONS AND INFORMATION FLOWS FOR SERVICES IN THE ISDN Q.60Q.99 CLAUSES APPLICABLE TO ITU-T STANDARD SYSTEMS Q.100Q.119 SPECIFICATIONS OF SIGNALLING SYSTEM No.
3、4 Q.120Q.139 SPECIFICATIONS OF SIGNALLING SYSTEM No. 5 Q.140Q.199 SPECIFICATIONS OF SIGNALLING SYSTEM No. 6 Q.250Q.309 SPECIFICATIONS OF SIGNALLING SYSTEM R1 Q.310Q.399 SPECIFICATIONS OF SIGNALLING SYSTEM R2 Q.400Q.499 DIGITAL EXCHANGES Q.500Q.599 INTERWORKING OF SIGNALLING SYSTEMS Q.600Q.699 SPECIF
4、ICATIONS OF SIGNALLING SYSTEM No. 7 Q.700Q.799 Q3 INTERFACE Q.800Q.849 DIGITAL SUBSCRIBER SIGNALLING SYSTEM No. 1 Q.850Q.999 PUBLIC LAND MOBILE NETWORK Q.1000Q.1099 INTERWORKING WITH SATELLITE MOBILE SYSTEMS Q.1100Q.1199 INTELLIGENT NETWORK Q.1200Q.1699 SIGNALLING REQUIREMENTS AND PROTOCOLS FOR IMT-
5、2000 Q.1700Q.1799 SPECIFICATIONS OF SIGNALLING RELATED TO BEARER INDEPENDENT CALL CONTROL (BICC) Q.1900Q.1999 BROADBAND ISDN Q.2000Q.2999 General aspects Q.2000Q.2099 Signalling ATM adaptation layer (SAAL) Q.2100Q.2199 Signalling network protocols Q.2200Q.2299 Common aspects of B-ISDN application pr
6、otocols for access signalling and network signalling and interworking Q.2600Q.2699 B-ISDN application protocols for the network signalling Q.2700Q.2899 B-ISDN application protocols for access signalling Q.2900Q.2999 For further details, please refer to the list of ITU-T Recommendations. ITU-T Rec. Q
7、.2150.3 (12/2002) i ITU-T Recommendation Q.2150.3 Signalling transport converter on SCTP Summary This Recommendation specifies the Signalling Transport Converter on the Stream Control Transmission Protocol (SCTP). This Signalling Transport Converter on SCTP utilizes the services offered by the SCTP.
8、 The sublayer structure, the PDU structures of the signalling transport converter sublayer, and the mechanisms for the provision of the generic signalling transport service are defined in depth. The intent of this Recommendation is to provide a protocol specification that can be used in an IP enviro
9、nment for the provision of a signalling transport service. In particular, this protocol provides a Generic Signalling Transport Service that is used by AAL type 2 and Bearer Independent Call Control (BICC) signalling protocols Source ITU-T Recommendation Q.2150.3 (2002) was prepared by ITU-T Study G
10、roup 11 (2001-2004) and approved under the WTSA Resolution 1 procedure on 29 December 2002. Keywords (AAL) ATM Adaptation Layer, (BICC) Bearer Independent Call Control, (IP) Internet Protocol, (SCTP) Stream Control Transmission Protocol, (STC) Signalling Transport Converter. ii ITU-T Rec. Q.2150.3 (
11、12/2002) 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 quest
12、ions 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
13、 on these 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 ISO and IEC. NOTE In this Recommendation, t
14、he expression “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 claime
15、d Intellectual 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
16、 received 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. ITU 2003 All rights res
17、erved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. ITU-T Rec. Q.2150.3 (12/2002) iii CONTENTS Page 1 Scope 1 2 References. 1 2.1 Normative references 1 2.2 Bibliography. 1 3 Definitions 2 4 Abbreviations 2 5 General description
18、 of the signalling transport converter on SCTP. 2 5.1 Structure of the signalling transport converter on SCTP sublayer. 2 5.2 Services provided by the STC 3 5.3 Functions of the STC 4 6 Elements for layer-to-layer communication . 4 6.1 The generic signalling transport service. 4 6.2 The Service prov
19、ided by SCTP 5 6.3 Primitives between the STC and layer management 9 7 Protocol elements for peer-to-peer communication . 10 7.1 STC messages (STC-PDUs). 10 7.2 STC state variable. 11 7.3 STC timers 11 7.4 Provisioned STC parameters 11 8 Specification of the STC. 12 8.1 Overview 12 8.2 Procedures of
20、 the STC 13 8.3 State transition table . 15 Appendix I Protocol Implementation Conformance Statement (PICS) Proforma 15 ITU-T Rec. Q.2150.3 (12/2002) 1 ITU-T Recommendation Q.2150.3 Signalling transport converter on SCTP 1 Scope This Recommendation specifies the signalling transport converter sublay
21、er on top of the Stream Control Transmission Protocol (SCTP) specified in IETF RFC 2960 2 and RFC 3309 5 which specifies a reliable transport protocol operating over a connectionless packet network such as IP. This Recommendation covers the specification of the sublayer structure, the PDU structures
22、 of the signalling transport converter sublayer, and the procedures for the provision of the signalling transport service. When this Signalling Transport Converter on SCTP is applied for a signalling protocol entity, that entity is liberated from considering the peculiarities of the underlying signa
23、lling transport service. This is achieved by relying on a generic signalling transport service that is provided, for example, by the sublayer specified in this Recommendation. This Recommendation describes the interactions between the Signalling Transport Converter (STC) and the next higher layer, e
24、.g., the AAL type 2 6, 8 or BICC 7 signalling protocol entity, between the STC and the SCTP, and between the STC and layer management. 2 References 2.1 Normative references The following ITU-T Recommendations and other references contain provisions which, through reference in this text, constitute p
25、rovisions of this Recommendation. At the time of publication, the editions indicated were valid. All Recommendations and other references are subject to revision; users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommend
26、ations and other references listed below. A list of the currently valid ITU-T Recommendations is regularly published. The reference to a document within this Recommendation does not give it, as a stand-alone document, the status of a Recommendation. 1 ITU-T Recommendation Q.2150.0 (2001), Generic si
27、gnalling transport service. 2 IETF RFC 2960 (2000), Stream Control Transmission Protocol. 3 ITU-T Recommendation X.200 (1994), Information technology Open Systems Interconnection Basic Reference Model: The basic model. 4 ITU-T Recommendation X.210 (1993), Information technology Open Systems Intercon
28、nection Basic Reference Model: Conventions for the definition of OSI services. 5 IETF RFC 3309 (2002), Stream Control Transmission Protocol (SCTP) Checksum Change. 2.2 Bibliography The following ITU-T Recommendations and other documents contain information that may be useful to understanding the usa
29、ge of this Recommendation. There are no additional provisions of this Recommendation derived from these documents that are not already contained in the text of this Recommendation. 6 ITU-T Recommendation Q.2630.1 (1999), AAL type 2 signalling protocol Capability Set 1. 7 ITU-T Recommendation Q.1902.
30、1 (2001), Bearer Independent Call Control Protocol (Capability Set 2): Functional description. 2 ITU-T Rec. Q.2150.3 (12/2002) 8 ITU-T Recommendation Q.2630.2 (2000), AAL type 2 signalling protocol Capability Set 2. 9 IETF RFC 791 (1981), Internet Protocol (IPv4). 10 IETF RFC 2460 (1998), Internet P
31、rotocol (IPv6). 11 ITU-T Recommendation Q.2110 (1994), B-ISDN ATM adaptation layer Service specific connection oriented protocol (SSCOP). 12 ITU-T Recommendation Q.701 (1993), Functional description of the message transfer part (MTP) of Signalling System No.7. 13 ITU-T Recommendation Q.2210 (1996),
32、Message transfer part level 3 functions and messages using the services of ITU-T Recommendation Q.2140. 3 Definitions This Recommendation is based upon the concepts developed in ITU-T Recs X.200 3 and X.210 4 as well as definitions specified in clause 1.4 of IETF RFC 29602. 4 Abbreviations This Reco
33、mmendation uses the following abbreviations: BICC Bearer Independent Call Control CIC Call Instance Code IANA Internet Assigned Numbers Authority IETF Internet Engineering Task Force IP Internet Protocol MTP3 Message Transfer Part level 3 (Narrowband) MTP3b Message Transfer Part level 3 (Broadband)
34、MTU Maximum Transmission Unit PDU Protocol Data Unit SCTP Stream Control Transmission Protocol SSCOP Service Specific Connection Oriented Protocol STC Signalling Transport Converter For SCTP specific abbreviations, refer to clause 1.5 of IETF RFC 2960 2. 5 General description of the signalling trans
35、port converter on SCTP 5.1 Structure of the signalling transport converter on SCTP sublayer The sublayer providing the Signalling Transport Converter (STC) resides on top of the Stream Control Transmission Protocol (SCTP). It employs the services provided by the SCTP defined in IETF RFC 2960 2 and R
36、FC 3309 5. The STC provides the service that is requested by the Generic Signalling Transport Service defined in ITU-T Rec. Q.2150.0 1, where the signalling protocol makes use of this service. The complete protocol stack is illustrated in Figure 5-1. ITU-T Rec. Q.2150.3 (12/2002) 3 This Recommendati
37、on specifies: the interactions between the STC and the STC and the signalling protocol entity; the interactions between the STC and the SCTP layer; and the interactions between the STC and layer management. Q.2150.3_F05-1Signalling applicationSAPPrimitivesGeneric signallingtransport serviceExamples(
38、Q.2150.0)SAPPrimitivesSignalling transport converter on SCTP(this Recommendation)Q.2150.3SCTP signallingtransport serviceStream Control Transmission Protocol (SCTP)RFC 2960 and RFC 3309Internet Protocol (IPv4) Internet Protocol (IPv6)RFC 791 RFC 2460Figure 5-1/Q.2150.3 Structure of the Signalling Tr
39、ansport Converter on SCTP 5.2 Services provided by the STC The STC provides for the transparent transfer of data, i.e., signalling application (STC user) data between peer STC users. The supporting communication resources to achieve this transfer stay invisible to the signalling application. In part
40、icular, the STC service provides for: a) Independence from the underlying transmission media The STC service relieves its users from all concerns of the manner in which the STC service is provided. Except for possible influences of the quality of service, the transfer of data over different underlyi
41、ng networks is, thus, invisible. b) Transparency of the information transferred The STC service provides for the transparent transfer of octet-aligned STC user data. It does not restrict the content, format, or coding of the information, nor is there ever a need to interpret its structure or meaning
42、. c) Management of associations The STC service provides for a permanent connection service. As the underlying service (SCTP) needs to have a signalling association established, the STC establishes and maintains this connection on behalf of its user; the user is informed about the availability/unava
43、ilability of the data transfer service. 4 ITU-T Rec. Q.2150.3 (12/2002) 5.3 Functions of the STC The STC performs the following functions: a) Association establishment and maintenance This function provides for the establishment and maintenance of an SCTP signalling association. The STC will attempt
44、 to reestablish a new SCTP association on behalf of its user in the event of loss of SCTP connectivity. b) Service availability reporting to the STC user This function reports the availability or unavailability of an SCTP service to the STC user and also to Layer Management. c) Maximum length indica
45、tion to the STC user This function indicates to the STC user the maximum length of the PDU that the STC can transfer; indicated at creation of the STC entity. d) Call Instance Code (CIC) control indication to the STC user This function indicates to the STC user, at creation of the STC entity, whethe
46、r it serves as the controlling node of the call association. In addition, the following SCTP services are used: a) Acknowledged error-free non-duplicated transfer of user data. b) Sequenced delivery of user messages within single streams. Also, the following SCTP services may be used: a) Data fragme
47、ntation to conform to discovered path MTU size. b) Sequenced delivery of user messages within multiple streams. c) Bundling of multiple user messages into a single SCTP packet. d) Network-level fault tolerance through supporting of multi-homing at either or both ends of an association. e) Appropriat
48、e IP congestion avoidance behaviour. 6 Elements for layer-to-layer communication 6.1 The generic signalling transport service The Generic Signalling Transport Service is specified in ITU-T Rec. Q.2150.0 1. For convenience, a summary of the primitives for accessing the service is reproduced in Table
49、6-1. In the event of any difference between this table and the definitions in ITU-T Rec. Q.2150.0 1, the definitions in ITU-T Rec. Q. 2150.0 1 take precedence. ITU-T Rec. Q.2150.3 (12/2002) 5 Table 6-1/Q.2150.3 Primitives and parameters of the generic signalling transport sublayer Type Primitive generic name Request Indication Response Confirm START-INFO Max_Length CIC_Control IN-SERVICE Level OUT-OF-SERVICE (Note 1) CONGESTION LevelTRANSFER Sequence Control STC User
