1、INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Q.784.3 SERIES Q: SWITCHING AND SIGNALLING Specifications of Signalling System No. 7 - Test specification (I 2/99) ISUP97 basic call control procedures - Test Suite Structure and Test Purposes (TSS all users
2、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 Recommendations is regularly published. i ITU-T Recommendation Q.761 (1993), Functional des
3、cription of the ISDN User Part of Signalling System No. 7. 23 ITU-T Recommendation 4.762 (1993), General function of messages and signals of the ISDN User Part of Signalling System No. 7. STD.ITU-T RECMN Q.784-3-ENGL 1999 4862593 0689373 871 ITU-T Recommendation 4.763 (1997), Signalling System No. 7
4、 - ISDN User Part Formats and codes. ITU-T Recommendation 4.764 (1997), Signalling System No. 7 - ISDN User Part Signalling procedures. CCITT Recommendation 4.767 (1991), Applicution of the ISDN User Part of CCITT Signalling System No. 7 for international ISDN interconnections. ITU-T Recommendation
5、Q.850 (1993), Usage of cause and location in the Digital Subscriber Signalling System No. I and the Signalling $stern No. 7 ISDN User Part. ISO/IEC 9646-1 : 1994, Information technology Open Systems Interconnection - Conformance testing methodology and framework - Part I : General concepts. ISO/IEC
6、9646-2: 1994, Information technology - Open Systems Interconnection - Conformance testing methodology and framework - Part 2: Abstract Test Suite speciJcation. ISO/IEC 9646-3: 1992, Information technology - Open Systems Interconnection - Conformance testing methodology and framework - Purt3: The Tre
7、e and Tubular Combined Notation (TTCN). ISO/IEC 9646-5: 1994, Information technology - Open Systems Interconnection - Conformance testing methodology and framework - Part 5: Requirements on test laboratories and clients for the conformance assessment process. ISO/IEC 9646-7: 1995, Information techno
8、logy - Open Systems Interconnection - Conformance testing methodology and pamework - Part 7: Implementation Conformance Statements. ITU-T Recommendation 4.784.1 (1996), ISUP basic call test speczjication: Validation and compatibility for ISUP92 and Q. 767protocols. CCITT Recommendation E.164 (1988),
9、 Numberingplan for the ISDN era. Definitions and abbreviations Definitions For the purposes of this ATS specification, the following definitions apply: - - In particular, the following terms apply: 3.1.1 Abstract Test Case (ATC): A complete and independent specification of the actions required to ac
10、hieve a specific test purpose, defined at the level of abstraction of a particular Abstract Test Method, starting in a stable testing state and ending in a stable testing state (see 3.3.3 of 7). 3.1.2 Abstract Test Method (ATM): The description of how an NT is to be tested, given at an appropriate l
11、evel of abstraction to make the description independent of any particular realization of a Means of Testing, but with enough detail to enable abstract test cases to be specified for this method (see 3.3.5 of 7). 3.1.3 Abstract Test Suite (ATS): A test suite composed of abstract test cases (see 3.3.6
12、 of 7). 3.1.4 Implementation Under Test (IUT): An implementation of one or more OS1 protocols in an adjacent user/provider relationship, being part of a real open system which is to be studied by testing (see 3.3.43 of 7). terms defined in ISDN User Part (ISUP) reference specification i to 4; terms
13、defined in ISO/IEC 9646-1 7, ISO/IEC 9646-3 9 and in ISO/IEC 9646-7 i i. STD.1TU-T RECflN Q-784.3-ENGL LTTT 4Bb259L ObB91i74 708 W 3.1.5 ISDN number: A number conforming to the numbering and structure specified in CCITT Recommendation E. 164 131. 3.1.6 Means of Testing (MOT): The combination of equi
14、pment and procedures that can perform the derivation, selection, parameterization and execution of test cases, in conformance with a reference standardized ATS, and can produce a conformance log (see 3.3.54 of 7). 3.1.7 PICS proforma: A document, in the form of a questionnaire, which when completed
15、for an implementation or system becomes the PICS. 3.1.8 PIXIT proforma: A document, in the form of a questionnaire, which when completed for the TUT becomes the PIXIT. 3.1.9 Point of Control and Observation: A point within a testing environment where the occurrence of test events is to be controlled
16、 and observed, as defined in an Abstract Test Method (see 3.3.64 of 7). 3.1.10 Pre-test condition: A setting or state in the IUT which cannot be achieved by providing stimulus fi-om the test environment. 3.1.11 Protocol Implementation Conformance Statement (PICS): A statement made by the supplier of
17、 a protocol claimed to conform to a given specification, stating which capabilities have been implemented (see 3.3.39 and 3.3.80 of 7). 3.1.12 Protocol Implementation extra Information for Testing (PIXIT): A statement made by a supplier or implementor of an IUT (protocol) which contains or reference
18、s all of the information related to the IUT and its testing environment, which will enable the test laboratory to run an appropriate test suite against the IUT (see 3.3.41 and 3.3.81 of 7). 3.1.13 System Under Test (SUT): The real open system in which the IUT resides (see 3.3.103 of 7). 3.1.14 User:
19、 The access protocol entity at the User side of the user-network interface where a T reference point or coincident S and T reference point applies. 3.2 Abbreviations The ISUP message acronyms can be found in Table 2/Q.762 2. This Recommendation uses the following abbreviations: ASP Abstract Service
20、Primitive ATC Abstract Test Case ATM Abstract Test Method ATS Abstract Test Suite CIC Circuit Identification Code CntrlE Controlling Exchange DLE Destination Local Exchange DSS 1 ICs Implementation Conformance Statement IncIE Incoming International Exchange IntermE Intermediate Exchange ISC Intemati
21、onal Switching Centre ISDN Integrated Services Digital Network Digital Subscriber System No. 1 STD-ITU-T RECMM d.784.3-ENGL 1779 4862573 Ob87375 b44 = ISUP ISDN User Part ITE International Transit Exchange IUT Implementation Under Test IWorkE Interworking Exchange LAPD LT Low er Tes ter MMI Man Mach
22、ine Interface MOT Means Of Testing MTC Main Test Component MTP Message Transfer Part “I Network-network interface NTE National Transit Exchange OLE Originating Local Exchange OutIE Outgoing International Exchange PCM Pulse Code Modulation PCO PCTR Protocol Conformance Test Report PDU Protocol Data U
23、nit PICS Protocol Implementation Conformance Statement PIXIT PTC Parallel Test Component SCS System Conformance Statement SP Signalling Point SUT System Under Test TCP Test Coordination Procedure TP Test Purpose TSS Test Suite Structure TSS and TP TTCN TypeA Type A exchange TypeB Type B exchange UNI
24、 User-network interface UT Upper Tester Link Access Protocol for the D-channel Point of Control and Observation Protocol Implementation extra Information for Testing Test Suite Structure and Test Purposes Tree and Tabular Combined Notation STD-ITU-T RECMN Q.784.3-ENGL 3999 M 48b2593 0687376 580 4 Im
25、plementation under test and test methods 4.1 The system under test (SUT) is an exchange. Identification of the system and implementation under test capabilities and functions ISUP92 I Access Tll1420-96 ISUP ISDN User Part IUT Implementation Under Test MMI Man Machine Interface SUT System Under Test
26、Figure VQ.784.3 - Exchange as SUT The implementation under test (IUT) is the ISUP97 implementation in this exchange, as shown in Figure 1. The aim of the ISUP implementation is to assure capabilities and functions for circuit and signalling supervision on one hand and for call handling on the other.
27、 Circuit supervision is done mainly through the MMI (man machine interface) of the exchange. The MMI interface is implementation dependent and thus not standardized. The effects of signalling procedures of the ISDN User Part can be observed on the NNI (network-network interface), on the circuits con
28、trolled by the ISUP. The ISUP signalling protocol can be observed on the SS No. 7 link on the “I. The ISUP implementation will in some exchanges have to intenvork with the access signalling system on the UNI (user-network interface) and involve call handling in order to establish end-to-end connecti
29、ons. From the ISUP reference standard several types of exchanges (or roles) can be identified as presented in Figure 2. STD-ITU-T RECMN Q.784.3-ENGL 1999 E 4B6259L Dh89L77 4L7 H local , intermediate local -_ / OLE Access . DLE Gateway IncIE Transit Gateway NTE OutIE I ITE -I 1 Access national networ
30、k network network national / international / T1181430-96 DLE Destination Local Exchange IncIE Incoming Intemational Exchange ITE International Transit Exchange NTE National Transit Exchange OLE Originating Local Exchange OutIE Outgoing International Exchange Figure 2/Q.784.3 - Roles of exchanges The
31、 exchanges can be divided in two main groups according to their functionality: local exchanges, where calls originate and terminate, and intermediate exchanges, with transit functionality. Local exchanges are national, i.e. belong to a national network. Intermediate exchanges are national or interna
32、tional. The international intermediate exchanges which permit access to the international network are the gateway exchanges (incoming and outgoing), also called ISCs - international switching centres. The roles of the exchanges are summarized in Table 1. Table UQ.784.3 - Roles of exchanges Local Int
33、ermediate Exchange Exchange 4.2 The Abstract Test Method (ATM) chosen for the ISUP97 testing specification is the distributed multiparty test method. The ATM is defined at an appropriate level of abstraction so that the test cases may be specified appropriately, without adding restrictions to the im
34、plementation under test. The testing architectures are described in the following subclauses. The ATS is written in concurrent TTCN. ATM and testing configuration for ISUP97 4.2.1 Intermediate exchanges The configuration proposed for testing intermediate exchanges is shown in Figure 3. In order to t
35、est the protocol and functionality of transit and gateway exchanges, one needs to consider the incoming and outgoing side of the SUT. LT Physical aspects . Network service provider C Network service provider I Circuits I LT ISUP link SP c + 1 MNT I Circuits I LT ISUP link SP B CAB PCO for AB circuit
36、s CAC PCO for AC circuits IUT Implementation Under Test LAB PCO for signalling link AB LAC PCO for signalling link AC LT Lower Tester MNT Maintenance PCO PCO Point of Control and Observation SP Signalling Point TCP Test Coordination Procedures UT Upper Tester Figure 3/Q.784.3 - ISUP test method for
37、intermediate exchanges The IUT is observed and controlled from two ISUP links with associated circuits. The points of control and observation (PCO) are labelled LAB and CAB on one side, and LAC and CAC on the other. The LAB and LAC PCOs are used by the lower testers (LT) for controlling the ISUP sig
38、nalling link, whereas the CAB and CAC PCOs are used by the lower testers for observing circuit related events, such as connectivity, echo control check, alerting tone, etc. The ISUP PDUs to be sent and observed on the LAB PCO side allow for PDU constraints to be specified and coded down to the bit l
39、evel. The MNT PCO is used by the upper tester (UT) to control and observe the maintenance functions of the exchange. The underlying network service provider is the Message Transfer Part (MTP) protocol as specified in Recommendations Q.701-707. Figure 4 shows the actual used configuration for interme
40、diate exchanges, with a main test component (MTC), responsible for the A-B interface and a slave parallel test component (PTC), responsible for the C-A interface. The maintenance PCO (MNT) and the operator PCO (OPR), needed for a limited number of test cases are integrated in the MTC, for simplifyin
41、g reasons. The test coordination procedures (TCP) allow for communication between the testers. The test components are mostly implicitly coordinated (asynchronously); the TCPs are only used when it is necessary to obtain the verdict from the parallel test component. c Maintenance operator PTC I l l
42、ISUP signalling. circuits i i i IUT I SP c -m- MTC ISUP signalling, circuits SP E? Network service provider Network service provider T1181450-96 PAD o: - :+non - AD :-r- XTP x*-:-T-*f- * LD LIILUIL rLw u11 AD IIILGIILC IV1 IL 1Vlillll I GbL LolrilwIlrril CAC Circuit PCO on AC interface OPR Operator
43、PCO IUT Implementation Under Test PCO Point of Control and Observation LAB PCO for signalling link AB PTC Parallel Test Component LAC PCO for signalling link AC SP Signalling Point MNT Maintenance PCO TCP Test Coordination Procedure ligure 41v. 104.3 - 13 ur rest comigurarion Ior inrermeaiare excnan
44、ges 4.2.2 Local exchanges When testing a local exchange as specified in the reference standard, it is difficult, if not impossible, to observe only ISUP PDUs, if functionality such as connectivity, tones and announcements etc. associated with protocol events is to be considered and used to assign ve
45、rdicts. The reference standard often refers to actions or events initiated by or to be observed by the calling or called user. A roint or Lontrol or ubservation (YCU) Irom 1YUY (IUl) to the access side is needed, e.g. for stimulating the local exchange to originate a call (send an IAM). Another PCO
46、is needed to check connectivity or to check tones generated etc. by the local exchange. rnere is no exposea interrace nom 1SuY (me lui) towards the access side. kor practical testing purposes the natural choice is the access interface. It is therefore reasonable to make use of the access interface (
47、e.g. the user access interface DSSl) as a PCO and to use existing naming conventions for the abstract service primitives (ASPS) to be used on this PCO. Figure 5 presents a multiparty testing configuration for local exchanges. In this figure each tester has a single PCO. The PCO for the access uses t
48、he underlying access service provider (e.g. LAPD, in case of DSS1) for observing access events and stimulating the ISUP via the access. The ISUP implementation (IUT) cannot be tested without involving the user-network interface (UNI). STD-ITU-T RECMN d.784.3-ENGL 1799 YB62591 Ob89160 TO1 Circuits Ph
49、ysical aspects Announcements tones, etc. Access service provider Call handling r Network service provider T1181460-96 LT ISUP link SP B -fG- I ACH Access signalling PCO (D-channel) APH Access signalling PCO -channel) CAB Circuit PCO on AB interface IUT Implementation Under Test LAB PCO for signalling link AB LT Lower Tester MNT Maintenance PCO PCO SP Signalling Point TCP Test Coordination Procedures UNI User-Network Interface UT Upper Tester Point of Control and Observation Figure 5/Q.784.3 - ISUP test method for originating/destina
