Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); Interworking between Session Initiation Protocol (SIP) and Bearer Independent Call Control Protocol (BICC) or ISDN User Part (ISUP); Part 3: Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for Testing (PIXIT)

DTS/TISPAN-06025-3-NGN-R2

General Information

Status
Published
Publication Date
24-Sep-2009
Technical Committee
Current Stage
12 - Completion
Due Date
27-Sep-2009
Completion Date
25-Sep-2009
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ETSI TS 186 009-3 V2.1.1 (2009-09) - Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); Interworking between Session Initiation Protocol (SIP) and Bearer Independent Call Control Protocol (BICC) or ISDN User Part (ISUP); Part 3: Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for Testing (PIXIT)
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ETSI TS 186 009-3 V2.1.1 (2009-09)
Technical Specification

Telecommunications and Internet converged Services
and Protocols for Advanced Networking (TISPAN);
Interworking between Session Initiation Protocol (SIP) and
Bearer Independent Call Control Protocol (BICC) or
ISDN User Part (ISUP);
Part 3: Abstract Test Suite (ATS) and
partial Protocol Implementation eXtra
Information for Testing (PIXIT)




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2 ETSI TS 186 009-3 V2.1.1 (2009-09)



Reference
DTS/TISPAN-06025-3-NGN-R2
Keywords
ATS, BICC, IMS, interworking, ISUP, PIXIT, SIP,
testing
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ETSI

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3 ETSI TS 186 009-3 V2.1.1 (2009-09)
Contents
Intellectual Property Rights . 4
Foreword . 4
1 Scope . 5
2 References . 5
2.1 Normative references . 6
2.2 Informative references . 7
3 Definitions and abbreviations . 7
3.1 Definitions . 7
3.2 Abbreviations . 8
4 Abstract Test Method (ATM) . 9
4.1 Network architecture . 9
4.2 Protocol architecture. 10
4.3 Test architecture . 10
4.3.1 Interconnection of TS and SUT . 10
4.3.2 Test system architecture . 11
4.3.2.1 General . 11
4.3.2.2 Structure . 11
4.3.2.3 Interaction between TTCN-3 Executable (TE) and SUT Adapter (SA) . 12
4.3.2.3.1 Control of the SUT Adapter (SA) by using ASPs . 12
4.3.2.3.2 Sending and receiving SIP and ISUP/BICC messages . 16
4.3.2.3.2.1 General . 16
4.3.2.3.2.2 Sending and receiving SIP/IMS messages . 16
4.3.2.3.2.3 Security and messages compression feature . 17
4.3.2.3.2.4 Additional SA constraints . 17
4.3.2.3.3 Encoding/Decoding System requirements . 17
5 The ATS development process . 21
5.1 Requirements and Test Purposes . 21
5.2 ATS structure . 21
5.2.1 Test case grouping . 21
5.2.2 Test case identifiers . 22
5.3 ATS specification framework . 23
5.3.1 ATS Library . 23
5.3.2 Use of TTCN-3 . 24
5.3.2.1 General . 24
5.3.2.2 TTCN-3 naming conventions . 25
5.3.2.3 Additional TTCN-3 IMS/SIP and ISUP naming convention . 26
5.3.2.4 Additional concepts and conventions . 27
5.3.2.5 PICS information . 27
5.3.2.6 TTCN-3 comment tags . 27
5.4 ATS archive . 29
Annex A (normative): Partial PIXIT proforma . 30
A.1 Introduction . 30
A.2 PIXIT items . 30
A.2.1 Common PIXIT related to SIP and ISUP/BICC. 31
A.2.2 SIP/IMS -related PIXIT . 34
A.2.3 ISUP/BICC-related PIXIT . 35
Annex B (informative): TTCN-3 library modules . 47
B.1 Electronic annex, zip file with TTCN-3 code . 47
History . 48
ETSI

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4 ETSI TS 186 009-3 V2.1.1 (2009-09)
Intellectual Property Rights
IPRs essential or potentially essential to the present document may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
server (http://webapp.etsi.org/IPR/home.asp).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web
server) which are, or may be, or may become, essential to the present document.
Foreword
This Technical Specification (TS) has been produced by ETSI Technical Committee Telecommunications and Internet
converged Services and Protocols for Advanced Networking (TISPAN).
The present document is part 3 of a multi-part deliverable covering the Interworking between Session Initiation
Protocol (SIP) and Bearer Independent Call Control Protocol (BICC) or ISDN User Part (ISUP), as identified below:
Part 1: "Protocol Implementation Conformance Statement (PICS)";
Part 2: "Test Suite Structure and Test Purposes (TSS&TP)";
Part 3: "Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for Testing
(PIXIT)";
ETSI

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5 ETSI TS 186 009-3 V2.1.1 (2009-09)
1 Scope
The present document specifies the Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information
for Testing (PIXIT) proforma based on the Testsuite Structure and Testpurposes defined in TS 186 009-2 [1].
The TSS&TP have been developed to test the interworking between Session Initiation Protocol (SIP) and Bearer
Independent Call Control Protocol (BICC) or ISDN User Part, Profiles A and B. The ATS is sometimes referred to in
the present document as "SIP-ISUP-Interworking ATS".
The test notation used in the ATS is TTCN-3 (ES 201 873-1 [8]).
The following test specification- and design considerations can be found in the body of the present document:
• the overall test suite structure;
• the testing architecture;
• the test methods and port definitions;
• the test configurations;
• the design principles, assumptions, and used interfaces to the TTCN3 tester (System Simulator);
• TTCN styles and conventions;
• the partial PIXIT proforma;
• the modules containing the TTCN-3 ATS.
Annex A provides the Partial Implementation Extra Information for Testing (IXIT) Proforma of the ATS.
Annex B provides the Testing and Test Control Notation (TTCN-3) part of the ATS.
2 References
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific.
• For a specific reference, subsequent revisions do not apply.
• Non-specific reference may be made only to a complete document or a part thereof and only in the following
cases:
- if it is accepted that it will be possible to use all future changes of the referenced document for the
purposes of the referring document;
- for informative references.
Referenced documents which are not found to be publicly available in the expected location might be found at
http://docbox.etsi.org/Reference.
NOTE: While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee
their long term validity.
ETSI

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6 ETSI TS 186 009-3 V2.1.1 (2009-09)
2.1 Normative references
The following referenced documents are indispensable for the application of the present document. For dated
references, only the edition cited applies. For non-specific references, the latest edition of the referenced document
(including any amendments) applies.
[1] ETSI TS 186 009-2 (Release 2): "Telecommunications and Internet Converged Services and
Protocols for Advanced Networking (TISPAN); SIP-ISUP Interworking between the IP
Multimedia (IM) Core Network (CN)subsystem and Circuit Switched (CS) networks; Part 2: Test
Suite Structure and Test Purposes (TSS&TP) ".
NOTE: The latest version v2.y.z applies
[2] ETSI TS 102 351 (V2.1.1): "Methods for Testing and Specification (MTS); Internet Protocol
Testing (IPT); IPv6 Testing: Methodology and Framework".
[3] ETSI TS 186 009-1 (Release 2): "Telecommunications and Internet converged Services and
Protocols for Advanced Networking (TISPAN); SIP-ISUP Interworking between the IP
Multimedia (IM) Core Network (CN)subsystem and Circuit Switched (CS) networks; Part 1:
Protocol Implementation Conformance Statement (PICS)".
NOTE: The latest version v2.y.z applies
[4] ETSI TS 129 163 (V7.12.0): "Digital cellular telecommunications system (Phase 2+) Universal
Mobile Telecommunications System (UMTS) Interworking between the IP Multimedia (IM) Core
Network (CN) subsystem and Circuit Switched (CS) networks (3GPP TS 29.163 Release 7).".
[5] ETSI TS 129 527: " Digital cellular telecommunications system (Phase 2+); Universal Mobile
Telecommunications System (UMTS); TISPAN; Endorsement of the SIP-ISUP Interworking
between the IP Multimedia (IM) Core Network (CN) subsystem and Circuit Switched (CS)
networks [3GPP TS 29.163 (Release 7), modified] (3GPP TS 29.527 version 8.2.0 Release 8)".
[6] ITU-T Recommendation Q.2150.1 (2001): "Signalling Transport Converter on MTP3 and
MTP3b".
[7] ETSI TS 102 027-3 (V3.1.1): "Methods for Testing and Specification (MTS); Conformance Test
Specification for SIP (IETF RFC 3261); Part 3: Abstract Test Suite (ATS) and partial Protocol
Implementation eXtra Information for Testing (PIXIT) proforma".
[8] ETSI ES 201 873-1 (V3.1.1): "Methods for Testing and Specification (MTS); The Testing and
Test Control Notation version 3; Part 1: TTCN-3 Core Language".
[9] ETSI ES 201 873-5 (V3.1.1): "Methods for Testing and Specification (MTS); The Testing and
Test Control Notation version 3; Part 5: TTCN-3 Runtime Interface (TRI)".
[10] ETSI ES 201 873-6 (V3.1.1): "Methods for Testing and Specification (MTS); The Testing and
Test Control Notation version 3; Part 6: TTCN-3 Control Interface (TCI)".
[11] ISO/IEC 9646-1 (1992): "Information Technology - Open Systems Interconnection - Conformance
Testing Methodology and Framework - Part 1: General concepts".
[12] ISO/IEC 9646-7 (1994): "Conformance testing methodology and framework -
Part 7: Implementation Conformance Statement".
[13] ITU-T Recommendation Q.761 (2000): "Specifications of Signalling System No.7 ISDN User
Part (ISUP)".
[14] ITU-T Recommendation Q.762 (2000): "Specifications of Signalling System No.7 ISDN User
Part (ISUP)".
[15] ITU-T Recommendation Q.763 (2000): "Specifications of Signalling System No.7 ISDN User
Part (ISUP); ISDN user part formats and codes".
[16] ITU-T Recommendation Q.764 (2000): "Specifications of Signalling System No.7 ISDN User
Part (ISUP)".
ETSI

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7 ETSI TS 186 009-3 V2.1.1 (2009-09)
[17] IETF RFC 3261 (2002): "SIP: Session Initiation Protocol".
[18] ITU-T Recommendation E.164: "The international public telecommunication numbering plan".
[19] ETSI EN 300 356-1 (V4.2.1): "Integrated Services Digital Network (ISDN); Signalling System
No.7 (SS7); ISDN User Part (ISUP) version 4 for the international interface; Part 1: Basic services
[ITU-T Recommendations Q.761 to Q.764 (1999) modified]".
[20] ITU-T Recommendation Q.931: "ISDN user-network interface layer 3 specification for basic call
control".
[21] ETSI EN 300 097-1: "Integrated Services Digital Network (ISDN); Connected Line Identification
Presentation (COLP) supplementary service; Digital Subscriber Signalling System No. one
(DSS1) protocol; Part 1: Protocol specification ".
[22] IETF RFC 2617: "HTTP Authentication: Basic and Digest Access Authentication".
[23] IETF RFC 1321: "The MD5 Message-Digest Algorithm".
2.2 Informative references
The following referenced documents are not essential to the use of the present document but they assist the user with
regard to a particular subject area. For non-specific references, the latest version of the referenced document (including
any amendments) applies.
Not applicable.
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the terms and definitions given in:
• SIP/ISUP interworking reference specification is defined in TS 129 163 [4] and TS 129 527 [5];
• ISDN layer 3 reference specification is defined in EN 300 356-1 [19];
• ISDN User Part (ISUP) reference specification are defined in EN 300 356-1 [19];
• ISO/IEC 9646-1 [11] and ISO/IEC 9646-7 [12];
• ES 201 873-1 [8] (TTCN-3).
and the following apply:
Abstract Test Case (ATC): complete and independent specification of the actions required to achieve 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
Abstract Test Method (ATM): description of how an IUT is to be tested, given at an appropriate level 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
Abstract Test Suite (ATS): test suite composed of abstract test cases
Implementation Under Test (IUT): implementation of one or more OSI protocols in an adjacent user/provider
relationship, being part of a real open system which is to be studied by testing
Means of Testing (MOT): combination of equipment 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
ETSI

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8 ETSI TS 186 009-3 V2.1.1 (2009-09)
PICS proforma: document, in the form of a questionnaire, which when completed for an implementation or system
becomes the PICS
PIXIT proforma: document, in the form of a questionnaire, which when completed for the IUT becomes the PIXIT
point of Control and Observation: point within a testing environment where the occurrence of test events is to be
controlled and observed, as defined in an Abstract Test Method
pre-test condition: setting or state in the IUT which cannot be achieved by providing stimulus from the test
environment
Protocol Implementation Conformance Statement (PICS): statement made by the supplier of a protocol claimed to
conform to a given specification, stating which capabilities have been implemented
Protocol Implementation eXtra Information for Testing (PIXIT): statement made by a supplier or implementor of
an IUT (protocol) which contains or references 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
SIP number: number conforming to the numbering and structure specified in ITU-T Recommendation E.164 [18]
System Under Test (SUT): real open system in which the IUT resides
3.2 Abbreviations
For the purposes of the present document, the abbreviations given in ITU-T Recommendation Q.762 [14] and the
following apply:
ASP Abstract Service Primitive
NOTE: Exchanged between entities inside the TS or between the user of the ATS (operator) and the TS.
ATC Abstract Test Case
ATM Abstract Test Method
ATM Asynchroneous Transfer Mode
ATS Abstract Test Suite
BCI Backward Call Indicators
BICC Bearer Independent Call Control
CIC Circuit Identification Code
DSS1 Digital Subscriber System No. 1
EDS Encoding/Decoding System
FCI Forward Call Indicators
G/W Type 1 GateWay Type 1
G/W Type 2 GateWay Type 1
IETF Internet Engineering Task Force
ISDN Integrated Services Digital Network
ISUP ISDN User Part
IUT Implementation Under Test
IWU InterWorking Unit
LT Lower Tester
MOT Means Of Testing
MTP Message Transfer Part
NCI Nature of Connection Indicators
NGN Next Generation Network
OCN Original Called Number
PA Platform Adapter
PICS Protocol Implementation Conformance Statement
PIXIT Protocol Implementation eXtra Information for Testing
PTC Parallel Test Component
RDN Redirecting Number
RNN Redirection Number
SA System Adapter
SDP Session Description Protocol
SIP Session Initiation Protocol
ETSI

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9 ETSI TS 186 009-3 V2.1.1 (2009-09)
SN Signalling Node
STC Signalling Transport Converter
NOTE: According to ITU-T Recommendation Q.2150.1 [6].
SUT System Under Test
TC Test Case
TCI TTCN-3 Control Interface
TCP Test Coordination Procedures
TD Test Description
TE Test Equipment
TISPAN Telecommunications and Internet converged Services and Protocols for Advanced Networking
TL Test Logging
TM Test Management
TMR Transmission Medium Requirement
TP Test Purpose
TS Test System
TSS Test Suite Structure
TSS&TP Test Suite Structure and Test Purposes
TTCN Tree and Tabular Combined Notation
TTCN-3 Testing and Test Control Notation edition 3
4 Abstract Test Method (ATM)
4.1 Network architecture
Figures 1 and 2 show the network architecture for SIP-ISUP/BICC Interworking Units.
Figure 1 shows the network architecture for SIP-ISUP Interworking.


SIP ISUP
<-----------------------------------------> IWU <------------------------------------------>




Figure 1: Interworking between SIP and ISUP
Figure 2 shows the network architecture for SIP-BICC Interworking.


SIP BICC
<------------------------------------------>
<-----------------------------------------> IWU
<------------------------------------------>
 ATM bearer control



Figure 2: Interworking between SIP and BICC
NOTE: There are 3 profiles defined for IWU: Profile A, Profile B and Profile C (out of scope of the present
document). Figures 1 and 2 in clause 5 of TS 186 009-2 [1] show the substructures of the IWU for
Profiles A and B in terms of gateways and signalling nodes. In the ATS the SUT (IWU) represents either
a G/W Type 1 (Profile A) or the combination of G/W Type 2 and SN (Profile B).
ETSI

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10 ETSI TS 186 009-3 V2.1.1 (2009-09)
4.2 Protocol architecture
Figures 1 and 2 above show that there are 2 interfaces of the IWU (representing the SUT in the testing environment
described in the present document): a SIP interface and an ISUP- or BICC interface.
Since the ISUP and BICC protocols are very similar (the latter one being derived from ISUP), they are treated here as
one protocol.
NOTE: No signalling is used within the SIP-ISUP-Interworking ATS to control the ATM bearer in case of BICC
(ASPs are used).
Figure Error! Bookmark not defined. shows the protocol architecture in 2 branches.
SUT



IUT IUT
SIP/IMS Extension ISUP BICC
SIP RFC 3261
  STC STC
Compression algorithms (2)

UDP TCP MTP 3 MTP 3b

Security Algoritms (2)
  MTP Layer 2 AAL
IPV4/IPV6 (1)

(LAN) G.703/G.704 ATM



NOTE 1: Both IPV4 and IPV6 addressing should be supported.
NOTE 2: Optional security and compression algorithms should be supported.

Figure 3: Protocol architecture of the SIP-ISUP-Interworking ATS
4.3 Test architecture
4.3.1 Interconnection of TS and SUT
Figure 4 shows the interconnection of TS and SUT in terms of signalling message flows.



SIP ISUP/
SUT
BICC
<------------------------>
<------------------------> IWU
<------------------------>
  ATM bearer control
(only for BICC)



Test

System

Figure 4: Interconnection of TS and SUT
ETSI

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11 ETSI TS 186 009-3 V2.1.1 (2009-09)
4.3.2 Test system architecture
4.3.2.1 General
Test systems that implement this ATS shall conform to the requirements as defined in this clause.
4.3.2.2 Structure
An abstract architecture for a test system (TS) implementing a TTCN-3 ATS is displayed in figure 5 and also stated in
ES 201 873-5 [9].
Test Management (TM)
Test Control (TC) Test Logging (TL)

TCI



TTCN-3 Executable (TE)
TTCN-3 Runtime System (T3RTS)
  Executable Test Suite (ETS)
Encoding/Decoding System


TRI



SUT Adapter (SA) Platform Adapter (PA)

Figure 5: Abstract Test System Architecture
A TS has two interfaces, the TTCN-3 Control Interface (TCI) and the TTCN-3 Runtime Interface (TRI), which specify
the interface between Test Management (TM) and TTCN-3 Executable (TE) entities, and TE, SUT Adapter (SA) and
Platform Adapter (PA) entities, respectively. Out of these two interfaces the TRI has been standardized in
ES 201 873-5 [9], whereas the specification and implementation of the TCI is in ES 201 873-6 [10].
The part of TS that deals with interpretation and execution of TTCN-3 modules, i.e. the Executable Test Suite (ETS), is
shown as part of the TTCN-3 Executable (TE). This ETS corresponds either to the executable code produced by a
TTCN-3 compiler or a TTCN-3 interpreter from the TTCN-3 ATS in a TS implementation. The remaining part of the
TS, which deals with any aspects that cannot be concluded from information being present in the TTCN-3 ATS alone,
can be decomposed into Test Management (TM), SUT Adapter (SA) and Platform Adapter (PA) entities. In general,
these entities cover a TS user interface, test execution control, test event logging, communication of test data with the
SUT, and timer implementation.
The part of SA used for SIP message transfer shall implement the TRI adaptation as well as the SIP transport protocol
architecture described in clause 4.2.
The Encoding/Decoding System (EDS) entity, as far as applied to SIP messages, with the TE and Test Logging (TL)
entity within the TM shall comply with the conventions defined in clause 4.3.2 of TS 102 027-3 [7].
The part of SA used for ISUP/BICC message transfer shall implement the TRI adaptation as well as the ISUP/BICC
transport protocol architecture described in clause 4.2. For BICC, in addition, the ATM bearer control shall be
implemented.
The Encoding/Decoding System (EDS) entity, as far as applied to ISUP/BICC messages, shall comply with the
conventions and requirements defined in the following clauses.
ETSI

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12 ETSI TS 186 009-3 V2.1.1 (2009-09)
4.3.2.3 Interaction between TTCN-3 Executable (TE) and SUT Adapter (SA)
4.3.2.3.1 Control of the SUT Adapter (SA) by using ASPs
Table 1 lists the ASPs used in the SIP-ISUP-Interworking ATS. Detailed descriptions of the ASPs together with their
parameters follow.
Table 1: List of ASPs
ASP Name Short description
InitializeIsupBicc_req Initialize ISUP/BICC part of the test system.
InitializeIsupBicc_cnf Answer whether all necessary ISUP/BICC test system
initializations have been successfully performed.
ISUP_BICC_MSG_req Used to send an ISUP/BICC message.
ISUP_BICC_MSG_ind Used to receive an ISUP/BICC message.
BearerSetup_req For BICC: request TS to setup the bearer connection between
TS and SUT.
BearerSetup_acc For BICC: answer to BearerSetup_req.
BearerSetup_ind For BICC: indication that the bearer has been setup.
BearerRelease_req For BICC: request to release established bearer conne
...

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