ETSI TS 186 001-2 V1.2.1 (2009-09)

Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); Network Integration Testing between SIP and ISDN/PSTN network signalling protocols; Part 2: Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for Testing (PIXIT) proforma specification

RTS/TISPAN-06052-2-NGN-R1

General Information

• Status: Published
• Publication Date: 24-Sep-2009
• Technical Committee: TISPAN 6 - TISPAN Testing
• Current Stage: 12 - Completion
• Due Date: 28-Sep-2009
• Completion Date: 25-Sep-2009

Standards Content (Sample)

ETSI TS 186 001-2 V1.2.1 (2009-09)
Technical Specification

Telecommunications and Internet converged Services and
Protocols for Advanced Networking (TISPAN);
Network Integration Testing between
SIP and ISDN/PSTN network signalling protocols;
Part 2: Abstract Test Suite (ATS) and partial Protocol
Implementation eXtra Information for Testing (PIXIT)
proforma specification


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2 ETSI TS 186 001-2 V1.2.1 (2009-09)



Reference
RTS/TISPAN-06052-2-NGN-R1
Keywords
ATS, interoperability, ISDN, PIXIT, PSTN, SIP,
testing, TTCN
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3 ETSI TS 186 001-2 V1.2.1 (2009-09)
Contents
Intellectual Property Rights . 4
Foreword . 4
1 Scope . 5
2 References . 5
2.1 Normative references . 6
2.2 Informative references . 6
3 Definitions and abbreviations . 7
3.1 Definitions . 7
3.2 Abbreviations . 7
4 Abstract Test Method (ATM) . 8
4.1 Network architecture . 8
4.2 Protocol architecture. 8
4.3 Test architecture . 9
4.3.1 Interconnection of TS and SUT . 9
4.3.2 Test System architecture . 9
5 The ATS development process . 10
5.1 Requirements and Test Purposes . 10
5.2 ATS structure . 11
5.2.1 Test case grouping . 11
5.2.2 Test case identifiers . 12
5.3 ATS specification framework . 12
5.3.1 ATS Library . 12
5.3.2 Use of TTCN-3 . 13
5.3.2.1 General . 13
5.3.2.2 TTCN-3 naming conventions . 14
5.4 ATS archive . 15
Annex A (normative): Partial PIXIT proforma . 16
A.1 Introduction . 16
A.2 PIXIT items . 16
A.2.1 SIP-related PIXIT . 16
A.2.2 ISDN-related PIXIT . 21
A.2.3 General PIXIT . 24
Annex B (informative): TTCN-3 library modules . 25
B.1 Electronic annex, zip file with TTCN-3 code . 25
Annex A (informative): Change history . 26
History . 27

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4 ETSI TS 186 001-2 V1.2.1 (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 2 of a multi-part deliverable covering the Network Integration Testing between SIP and
ISDN/PSTN network signalling protocols, as identified below:
Part 1: "Test Suite Structure and Test Purposes (TSS&TP) for SIP-ISDN";
Part 2: "Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for
Testing (PIXIT) proforma specification";
Part 3: "Test Suite Structure and Test Purposes (TSS&TP) for SIP-SIP".
Part 4: "Abstract Tests Suite (ATS) SIP-SIP".
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5 ETSI TS 186 001-2 V1.2.1 (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 Test Suite Structure and Test Purposes defined in [1].
The TSS&TP have been developed Network Integration Testing between SIP and ISDN/PSTN network signalling
protocols. The ATS is sometimes referred to in the present document as "SIP-ISDN-Interworking ATS".
The test notation used in the ATS is TTCN-3 ([3]).
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.
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6 ETSI TS 186 001-2 V1.2.1 (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 186 001 (Parts 1 and 3): "Telecommunications and Internet Converged Services and
Protocols for Advanced Networking (TISPAN); Network Integration Testing between SIP and
ISDN/PSTN network signalling protocols".
[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 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".
[4] 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)".
[5] 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)".
[6] ISO/IEC 9646-1 (1994): "Information technology - Open Systems Interconnection - Conformance
testing methodology and framework - Part 1: General concepts".
[7] ISO/IEC 9646-7 (1995): "Information technology - Open Systems Interconnection - Conformance
testing methodology and framework - Part 7: Implementation Conformance Statements".
[8] ITU-T Recommendation Q.931 (1998): "ISDN user-network interface layer 3 specification for
basic call control".
[9] 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".
[10] IETF RFC 3261 (2002): "SIP: Session Initiation Protocol".
[11] ETSI EN 383 001: "Telecommunications and Internet converged Services and Protocols for
Advanced Networking (TISPAN); Interworking between Session Initiation Protocol (SIP) and
Bearer Independent Call Control (BICC) Protocol or ISDN User Part (ISUP) [ITU-T
Recommendation Q.1912.5, modified]".
[12] ITU-T Recommendations Q.761 to Q.764 (1999): "Signalling System No.7 - ISDN User Part
(ISUP)".
[13] ITU-T Recommendation E.164 (2005): "The international public telecommunication numbering
plan".
[14] IETF RFC 4575: "A Session Initiation Protocol (SIP) Event Package for Conference State".
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.
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7 ETSI TS 186 001-2 V1.2.1 (2009-09)
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 [11], ISDN layer 3 reference specification [8], ISDN User Part (ISUP) reference specification [12], [6],
[7], [3] (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
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 (PCO): 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 [13]
System Under Test (SUT): real open system in which the IUT resides
3.2 Abbreviations
For the purposes of the present document, the following abbreviations 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
ATS Abstract Test Suite
DSS1 Digital Subscriber System No. 1
ETS Executable Test Suite
IETF Internet Engineering Task Force
ISDN Integrated Services Digital Network
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8 ETSI TS 186 001-2 V1.2.1 (2009-09)
IUT Implementation Under Test
IWU InterWorking Unit
LAN Local Area Network
MOT Means Of Testing
MTC Main Test Component
NGN Next Generation Network
PA Plateform Adapter
PA Platform Adapter
PCO Point of Control and Observation
PDU Protocol Data Unit
NOTE: Message exchanged between TS and SUT at a signalling interface.
PICS Protocol Implementation Conformance Statement
PIXIT Protocol Implementation eXtra Information for Testing
PTC Parallel Test Component
SA SUT Adapter
SDP Session Description Protocol
SIP Session Initiation Protocol
SUT System Under Test
TC Test Case
TCI TTCN-3 Control Interface
TCP Test Coordination Procedures
TD Test Description
TE Test Equipment
TL Test Logging
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
UDP Unreliable Datagram Protocol
4 Abstract Test Method (ATM)
4.1 Network architecture
Figures 1 and 2 show the network architecture for SIP-ISDN InterWorking Units (IWU).
Figure 1 shows the network architecture for SIP-ISDN Interworking.


SIP ISDN
<-----------------------------------------> IWU <------------------------------------------>




Figure 1: Interworking between SIP and ISDN
4.2 Protocol architecture
Figure 1 shows 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 ISDN interface.
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9 ETSI TS 186 001-2 V1.2.1 (2009-09)
Figure 2 shows the protocol architecture:
SUT



IUT IUT
SIP Q.931

UDP TCP
IP Q.921

(LAN) I.431



Figure 2: Protocol architecture of the SIP-ISDN-Interworking ATS
4.3 Test architecture
4.3.1 Interconnection of TS and SUT
Figure 3 shows the interconnection of TS and SUT in terms of signalling message flows.



SIP ISDN
SUT
<------------------------>
<------------------------> IWU






Test

System

Figure 3: Interconnection of TS and SUT
4.3.2 Test System architecture
An abstract architecture for a Test System (TS) implementing a TTCN-3 ATS is displayed in figure 4 and also stated
in [4].
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10 ETSI TS 186 001-2 V1.2.1 (2009-09)
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 4: 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 [4], whereas
the specification and implementation of the TCI is in [5].
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 [9].
The part of SA used for ISDN message transfer shall implement the TRI adaptation as well as the ISDN transport
protocol architecture described in clause 4.2.
The Encoding/Decoding System (EDS) entity, as far as applied to ISDN messages, shall comply with the conventions
and requirements defined in the following clauses.
5 The ATS development process
5.1 Requirements and Test Purposes
For each test purpose there is a table defined in clause 6 of [1]. The requirements applicable to this TP are given by a
reference to the relevant base specification. There are no explicit formulations of requirements.
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11 ETSI TS 186 001-2 V1.2.1 (2009-09)
5.2 ATS structure
5.2.1 Test case grouping
The ATS structure defined in table 1 is based on the structuring of Test Purposes in clause 6 of [1]. The group names in
columns 1 to 3 of table 1 are those assigned in the ATS; they are based on the names provided in clause 6 of [1], but use
the naming conventions defined for the ATS (see clause 5.3.2.2).
Table 1: ATS structure
Group Subgroup Sub-Subgroup Group Index
ISDN-SIP  1
Basic call 11
 Successful - Speech 1101
 Codec negotiation 1102
 Successful - UPDATE 1103
 Successful - DTMF Tests 1104
 Successful - UDI 1105
 Unsuccessful 1106
Sup. Services 12
 CLIP 1201
 CLIR 1202
 COLP/COLR 1203
 CFU 1204
 CFB 1205
 CFNR 1206
 CFNL 1207
 CD 1208
 HOLD 1209
 3PTY 1210
 CONF 1211
SIP-ISDN  2
Basic call 21
 Successful 3,1 kHz audio 2101
 Codec negotiation 2102
 DTMF 2103
 UDI 2104
 Unsuccessful 2105
Sup. Services 22
 CLIP/OIP 2201
 OIR/CLIR 2202
 TIP/COLP 2203
 TIR/COLR 2204
 CFU 2205
 CFB 2206
 CFNR 2207
 CD 2208
 TP 2209
 3PTY 2210
 HOLD 2211
 CONF 2212
 CW 2213
 ACR 2214
 CUG 2215
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12 ETSI TS 186 001-2 V1.2.1 (2009-09)
Group Subgroup Sub-Subgroup Group Index
SIP-SIP  5
Basic call 51
 Successful 5101
 Codec negotiation 5102
 Update 5103
 Unsuccessful 5104
Sup. Services 53
 OIP 5201
 OIR 5202
 TIP 5203
 TIR 5204
 HOLD 5205
 CFU 5206
 CFB 5207
 CFNR 5208
 CFNL 5209
 CD 5210
 CONF 5211

5.2.2 Test case identifiers
The test case names are built up according to the following scheme:
<"TC">"_"
where:
a) double quotes (") are used to enclose literal strings;
b) is the 4-digit number which uniquely identifies the path of groups/subgroups;
c) is the identifier from the TSS&TP document.
EXAMPLE: TC1101_IS___XX__001:
i) the identifier has Group index "1101", i.e. it is in the subgroup having complete path:
 SIP-ISDN/BasicCall/Successful - Speech/;
ii) the identifier is the first test case of this group/subgroup.
NOTE: This naming scheme provides a 1-1 correspondence of TP identifiers as defined in [1] and test case
names.
5.3 ATS specification framework
5.3.1 ATS Library
For this interworking ATS there are 2 applicable base protocols:
a) SIP protocol ([10]); and
b) ISDN protocol (ITU-T Recommendation Q.931 [8] series, plus associated standards for supplementary
services etc.).
Since e.g. the data structures of these 2 base protocols are independent, and other objects like test cases are common,
the TTCN-3 library modules are basically organized as:
1) SIP modules;
2) ISDN modules;
3) Common modules (generated for the present ATS);
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13 ETSI TS 186 001-2 V1.2.1 (2009-09)
4) LibCommon modules (taken from [2]).
Table 2 shows the organization of the ATS as library of modules.
Table 2: Library of modules
Module Class Module Id Description
LibCommon LibCommon_AbstractData Generic data types for a stack and its operations.
LibCommon_BasicTypesAndValues Basic type and value definitions (integer and Boolean).
LibCommon_DataStrings Bit and Octet string types.
LibCommon_Sync Co-ordination/synchronization of test components.
LibCommon_TextStrings Basic character and string types with fixed length.
LibCommon_Time Time handling functions and moduleparameter.
LibCommon_VerdictControl Basic functions for setting of test component verdicts.
AtsCommon General_Types Definitions are based on component type definitions from IPv6,
SCOP and common synchronization libraries.
SipIsdn_PICS Module Parameter declarations associated with PICS.
SipIsdn_PIXITS SIP-ISDN common Module Parameter declarations associated
with PIXIT.
SipIsdn_Testcases Test case functions.
SipIsdn_TestConfiguration Functions which implement the configuration of the SUT adapter
and mapping of test components for establishing and tearing down
different test configurations.
SipIsdn_TestExecution Module control: execute test cases depending on selection
conditions; repeat parameterized test cases based on the
"Variant-tables" defined in the test prose.
SipIsdn_TestSystem Common functions, components, ASPs controlling the test system.
SipAts SipIsdn_SIP_SDPTypes SIP SDP data types.
SipIsdn_SIP_TCFunctions PTC root functions for SIP-to-ISDN test cases.
SipIsdn_SIPSIP_TCFunctions PTC root functions for SIP-to-SIP test cases.
SipIsdn_SIP_Types SIP data types (messages, header fields) and parallel test
component (according to [9]).
SipIsdn_SIP_Templates Templates for SIP messages and header fields (according to [10]).
SipIsdn_SIP_Steps SIP auxiliary functions.
SipIsdn_SIP_XMLTypes SIP data types defined in XML (message body according to
RFC 4575 [14]).
XSDAUX Generic XML type system for TTCN-3.
IsdnAts SipIsdn_ISDN_Types ISDN data types (information element and message types
according to ITU-T Recommendation Q.931 [8] and ASP type
declarations).
SipIsdn_ISDN_Templates Templates for ISDN information elements, messages and ASPs.
SipIsdn_ISDN_Steps Test step declarations, including preambles, postambles and
default.
SipIsdn_ISDN_TCFunctions Test case functions running on the Isdn component.
SipIsdnASN1Types ASN.1 definitions for ISDN message parts (ASN.1 and TTCN-3
notation).

5.3.2 Use of TTCN-3
5.3.2.1 General
TTCN-3 as defined in [3] is used as ATS specification language.
A number of requirements have been identified for the development and production of the TTCN-3 specification for the
SIP/ISUP Interworking ATS:
1) Top-down design.
2) A uniquely defined testing architecture and test method.
3) Uniform TTCN-3 style and naming conventions.
4) TTCN-3 is human-readability.
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14 ETSI TS 186 001-2 V1.2.1 (2009-09)
5) TTCN-3 specification is feasible, implementable, compilable and maintainable.
6) Test cases shall be designed in a way to be easily adaptable, upwards compatible with the evolution of the base
protocol and protocol interworking of future releases.
7) The test declarations, data structures and data values shall be largely reusable.
8) Modularity and modular working method.
9) Minimizing the requirements of intelligence on the emulators of the lower testers.
10) Giving enough design freedom to the test equipment manufacturers.
Fulfilling these requirements should ensure the investment of the test equipment manufacturers and users of the ATS
having stable testing means for a relatively long period.
5.3.2.2 TTCN-3 naming conventions
Like in oth
...