SIST EN 300 138-4 V1.4.3:2005

• Abstract:

  To handle comments and incorporate appropriate corrections into the ATS of DSS1 L2

• Status: Published
• Publication Date: 31-Mar-2005
• ICS: 33.080 - Integrated Services Digital Network (ISDN)
• Technical Committee: SPN - Services and Protocols for Networks
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Apr-2005
• Due Date: 01-Apr-2005
• Completion Date: 01-Apr-2005
• Ref Project: ETSI EN 300 138-4 V1.4.3 (2000-05) - Integrated Services Digital Network (ISDN); Closed User Group (CUG) supplementary service; Digital Subscriber Signalling System No. one (DSS1) protocol; Part 4: Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for Testing (PIXIT) proforma specification for the user

SIST EN 300 138-4 V1.4.3:2005 is the Slovenian adoption of ETSI EN 300 138-4 V1.4.3 for the Integrated Services Digital Network (ISDN) Closed User Group (CUG) supplementary service over the Digital Subscriber Signalling System No. one (DSS1) protocol. It specifies the Abstract Test Suite (ATS) and a partial Protocol Implementation eXtra Information for Testing (PIXIT) proforma for the user side of the T reference point, so it is the conformance-testing document for implementations claimed to conform to EN 300 138-1. The document also defines the related test report and PIXIT templates needed to run and record the tests.

What does SIST EN 300 138-4 V1.4.3:2005 specify?

SIST EN 300 138-4 V1.4.3:2005 specifies how to test the user side of the CUG supplementary service for ISDN using DSS1. It is part 4 of a multi-part series, and it works with the protocol specification in EN 300 138-1 and the test-purpose document in EN 300 138-3.

The scope is limited to the user side of the T reference point, or the coincident S and T reference point, for implementations that conform to the stage three standard. Other parts of the series cover the protocol itself, the PICS proforma, and the network-side test material.

The document is organized into clauses 1 to 10 and five annexes.

Annex	What it covers
Annex A	Normative PCTR proforma
Annex B	Normative partial PIXIT proforma
Annex C	Normative ATS
Annex D	Informative general structure of an ATS
Annex E	Informative change record

What are the key requirements of SIST EN 300 138-4 V1.4.3:2005?

The standard is mainly a conformance-testing specification, so its key requirements are about how to structure, realize and report tests.

Test method and observation points

Clause 4 applies the remote test method for the CUG user ATS. The Point of Control and Observation (PCO) is named L and sits at the service access point between layers 2 and 3. In practice, that means verdicts are based on what the tester can observe at that lower interface, not on internal implementation details.

Clause 4 also uses a second informal PCO named O for test co-ordination procedures (TCP). That PCO is for control only, not observation, so it helps the test script say what the operator must do without letting those actions affect the verdict.

Test purposes and test case structure

Clause 5 states that there are no untestable test purposes associated with this ATS. That matters because each test purpose from EN 300 138-3 is intended to be covered by executable testing.

Clause 6 says the ATS follows a TTCN-like structure with declarations, constraints and dynamic behaviour. In practical terms, implementers and test tool builders need to preserve the declared types, parameters, variables and constraints so that the ATS can be turned into a working executable test suite.

Data description and ASN.1 usage

Clause 6.1 allows both TTCN and ASN.1 type definitions, and it uses ASN.1 where ordered or unordered data structures are easier to model or where base standards define remote operation components. This matters because the test suite needs to match the protocol data precisely enough for conformance testing, especially for embedded information elements.

Encoding rules

Clause 6.2.2 says the default encoding for ASN.1 constraints in this ATS is ISDN-style encoding, not BER. BER is only used when the table header explicitly says so. The clause also states that test campaigns should send a variety of BER length forms, including indefinite, short definite and long definite, so an implementation is checked against different encodings it may encounter in practice.

Matching and parameterization

Clause 6.2.5 uses static chaining and semi-dynamic chaining, where a fixed constraint can be combined with a value passed as a parameter. That means the same test structure can be reused while still adapting to the specific message content needed for a run. Clause 6.2.8 also defines matching values such as *, ? and -, which are used to express optional, wildcard or omitted data in test constraints.

Test case execution and naming

Clause 6.3 says each test case contains the test purpose text from EN 300 138-3, and test steps are used to avoid repetition. Clause 7 maps test purposes directly to test case names, so there is a one-to-one link between what the standard intends to test and the ATS test case that performs it. For users of the document, this makes it easier to trace a failed test back to the protocol requirement it addresses.

Reporting and conformance obligations

Clauses 8 to 10 define how conformance artifacts must be prepared. Annex A provides the PCTR proforma for reporting test results, annex B provides the partial PIXIT proforma needed to set up the test environment, and annex C provides the ATS that an executable test suite must realize. In practice, a test laboratory or test realizer must keep the report structure, PIXIT content and ATS content technically equivalent to the annexes.

What terms does SIST EN 300 138-4 V1.4.3:2005 define?

• Abstract Test Suite (ATS) - the set of abstract test cases, test steps and constraints used to assess protocol conformance.
• Implementation Under Test (IUT) - the implementation being checked by the tests.
• Lower Tester (LT) - the testing part that interacts with the IUT at the lower interface.
• Point of Control and Observation (PCO) - the point where the tester controls and observes protocol behaviour.
• Protocol Conformance Test Report (PCTR) - the report template used to record conformance test results.
• Protocol Implementation Conformance Statement (PICS) - the statement an implementer uses to declare what features the implementation supports.
• Protocol Implementation eXtra Information for Testing (PIXIT) - the extra information needed to set up and run tests on a specific implementation.
• System Under Test (SUT) - the complete system being tested, including the IUT and its test environment.
• UpperTester (UT) - the tester role above the IUT used in test co-ordination procedures.

Who uses SIST EN 300 138-4 V1.4.3:2005?

Test laboratories use this standard to prepare conformance tests, collect results and produce a PCTR. Test realisers use it to build an executable test suite and the associated Means Of Testing (MOT) from the ATS in annex C.

Equipment vendors and protocol implementers use it when they need to verify that a CUG user implementation conforms to EN 300 138-1. Clients of test laboratories use the PIXIT proforma to provide the information needed to configure the test campaign, including system details, protocol information and timer values.

It is also relevant to organizations that need evidence of protocol conformance for ISDN user-network interfaces, especially where DSS1 supplementary service testing is part of product acceptance or interoperability work.

What changed in SIST EN 300 138-4 V1.4.3:2005 from the previous edition?

The change record says the ATS was revised between EN 300 138-4 V1.3 and V1.4. It also notes earlier changes from ETS 300 138-4 to EN 300 138-4 V1.3, including conversion to EN layout, replacement of references to ETS 300 102 with EN 300 403-1, and updating non-specific references so they point to the latest versions.

Which standards are used with SIST EN 300 138-4 V1.4.3:2005?

Standard	What it contributes
EN 300 138-1	The protocol specification for the CUG supplementary service
EN 300 138-2	The PICS proforma for the same service
EN 300 138-3	The user-side TSS&TP document that supplies the test purposes
EN 300 196-1	The generic functional protocol background used for supplementary services and related ASN.1 structures
EN 300 403-1	The DSS1 signalling network layer for circuit-mode basic call control
ISO/IEC 9646-1 to -5	The conformance testing framework, ATS rules, TTCN, test realization, and laboratory/client requirements
ITU-T Recommendation I.411	The ISDN reference configurations used to define the T, S and coincident reference points
CCITT Recommendation X.209	The Basic Encoding Rules (BER) for ASN.1
ETS 300 102	A referenced basic call control standard that appears in the document history and earlier references

What does the SIST EN 300 138-4 V1.4.3:2005 document contain?

Annex A contains a structured PCTR template with identification data, IUT identification, test environment, conformance summaries, test campaign results and observations. Annex B contains the partial PIXIT proforma, including test laboratory data, SUT information, protocol information, parameters and timer values.

Annex C contains the ATS in both TTCN graphical form (TTCN.GR) and TTCN machine-processable form (TTCN.MP). The body of clause 6 explains how the ATS is built, including type definitions, constraints, encoding variations, alias definitions and dynamic test behaviour.

Annex D gives a general outline of ATS structure, which helps readers find the relevant part of a supplementary-service ATS quickly. Annex E records the changes between editions, so users can see how this version differs from earlier ones.

SLOVENSKI STANDARD
01-april-2005
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XSRUDEQLND
Integrated Services Digital Network (ISDN); Closed User Group (CUG) supplementary
service; Digital Subscriber Signalling System No. one (DSS1) protocol; Part 4: Abstract
Test Suite (ATS) and partial Protocol Implementation eXtra Information for Testing
(PIXIT) proforma specification for the user
Ta slovenski standard je istoveten z: EN 300 138-4 Version 1.4.3
ICS:
33.080 Digitalno omrežje z Integrated Services Digital
integriranimi storitvami Network (ISDN)
(ISDN)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

European Standard (Telecommunications series)
Integrated Services Digital Network (ISDN);
Closed User Group (CUG) supplementary service;
Digital Subscriber Signalling System No. one (DSS1) protocol;
Part 4: Abstract Test Suite (ATS) and partial Protocol
Implementation eXtra Information for Testing (PIXIT)
proforma specification for the user
�
2 ETSI EN 300 138-4 V1.4.3 (2000-05)
Reference
REN/SPS-05163-4
Keywords
ATS, CUG, DSS1, ISDN, PIXIT, supplementary
service, user
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ETSI
3 ETSI EN 300 138-4 V1.4.3 (2000-05)
Contents
Intellectual Property Rights.5
Foreword .5
1 Scope.6
2 References.6
3 Definitions and abbreviations .7
3.1 Definitions.7
3.2 Abbreviations .7
4 Abstract Test Method (ATM) .8
5 Untestable test purposes.8
6 ATS conventions.8
6.1 Declarations part .8
6.1.1 Type definitions .8
6.1.1.1 Simple type definitions.8
6.1.1.2 Structured type definitions .9
6.1.1.2.1 TTCN structured type definitions.9
6.1.1.2.2 ASN.1 structured type definitions.9
6.1.1.3 ASP type definitions.10
6.1.1.3.1 TTCN ASP type definitions.10
6.1.1.3.2 ASN.1 ASP type definitions .10
6.1.1.4 PDU type definitions.10
6.1.1.4.1 TTCN PDU type definitions.10
6.1.1.4.2 ASN.1 PDU type definitions .11
6.1.2 Test suite constants .11
6.1.3 Test suite parameters .11
6.1.4 Variables.11
6.1.4.1 Test suite variables.11
6.1.4.2 Test case variables .11
6.1.5 Test suite operation definitions.11
6.1.6 Alias definitions.11
6.2 Constraints part.11
6.2.1 Structured type constraint declaration.11
6.2.2 ASN.1 type constraint declaration .12
6.2.2.1 Specification of encoding rules .13
6.2.3 ASP type constraint declaration.13
6.2.3.1 ASN.1 ASP type constraint declaration .13
6.2.3.2 TTCN ASP type constraint declaration.13
6.2.4 PDU type constraint declaration .14
6.2.4.1 ASN.1 PDU type constraint declaration.14
6.2.4.2 TTCN PDU type constraint declaration .14
6.2.5 Chaining of constraints .14
6.2.5.1 Static chaining.14
6.2.5.2 Dynamic chaining.14
6.2.6 Derived constraint.14
6.2.7 Parameterized constraints .14
6.2.8 Value assignment.14
6.2.8.1 Specific values .14
6.2.8.2 Matching values .15
6.3 Dynamic part .15
6.3.1 Test cases.15
6.3.2 Test steps .15
6.3.3 Defaults.15
ETSI
4 ETSI EN 300 138-4 V1.4.3 (2000-05)
7 ATS to TP map.15
8 PCTR conformance.15
9 PIXIT conformance.16
10 ATS conformance .16
Annex A (normative): Protocol Conformance Test Report (PCTR) proforma.17
A.1 Identification summary .17
A.1.1 Protocol conformance test report.17
A.1.2 IUT identification.17
A.1.3 Testing environment.17
A.1.4 Limits and reservations.18
A.1.5 Comments.18
A.2 IUT conformance status .18
A.3 Static conformance summary.18
A.4 Dynamic conformance summary.18
A.5 Static conformance review report .19
A.6 Test campaign report.19
A.7 Observations.19
Annex B (normative): Partial PIXIT proforma.20
B.1 Identification summary .20
B.2 Abstract test suite summary .20
B.3 Test laboratory .20
B.4 Client (of the test laboratory).21
B.5 System Under Test (SUT).21
B.6 Protocol information .22
B.6.1 Protocol identification .22
B.6.2 IUT information .22
B.6.2.1 Parameters .22
B.6.2.2 Parameter values.22
B.6.2.3 Timer values .23
Annex C (normative): Abstract Test Suite (ATS).24
C.1 The TTCN Graphical form (TTCN.GR).24
C.2 The TTCN Machine Processable form (TTCN.MP) .24
Annex D (informative): General structure of ATS.25
Annex E (informative): Change record.26
E.1 Changes between EN 300 138-4 V1.3 and V1.4.26
E.2 Changes between ETS 300 138-4 and EN 300 138-4 V1.3 .26
History.27
ETSI
5 ETSI EN 300 138-4 V1.4.3 (2000-05)
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 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://www.etsi.org/ipr).
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 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 European Standard (Telecommunications series) has been produced by ETSI Technical Committee Services and
Protocols for Advanced Networks (SPAN).
The present document is part 4 of a multi-part EN covering the Digital Subscriber Signalling System No. one (DSS1)
protocol specification for the Integrated Services Digital Network (ISDN) Closed User Group (CUG) supplementary
service, as identified below:
Part 1: "Protocol specification";
Part 2: "Protocol Implementation Conformance Statement (PICS) proforma specification";
Part 3: "Test Suite Structure and Test Purposes (TSS&TP) specification for the user";
Part 4: "Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for Testing
(PIXIT) proforma specification for the user";
Part 5: "Test Suite Structure and Test Purposes (TSS&TP) specification for the network";
Part 6: "Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information for Testing (PIXIT)
proforma specification for the network".
National transposition dates
Date of adoption of this EN: 28 April 2000
Date of latest announcement of this EN (doa): 31 July 2000
Date of latest publication of new National Standard
or endorsement of this EN (dop/e): 31 January 2001
Date of withdrawal of any conflicting National Standard (dow): 31 January 2001
ETSI
6 ETSI EN 300 138-4 V1.4.3 (2000-05)
1 Scope
The present document specifies the Abstract Test Suite (ATS) and partial Protocol Implementation eXtra Information
for Testing (PIXIT) proforma for the User side of the T reference point or coincident S and T reference point (as
defined in ITU-T Recommendation I.411 [11]) of implementations conforming to the stage three standard for the Closed
User Group (CUG) supplementary service for the pan-European Integrated Services Digital Network (ISDN) by means
of the Digital Subscriber Signalling System No. one (DSS1) protocol, EN 300 138-1 [2].
EN 300 138-3 [4] specifies the Test Suite Structure and Test Purposes (TSS&TP) related to this ATS and partial PIXIT
proforma specification. Other parts specify the TSS&TP and the ATS and partial PIXIT proforma for the Network side
of the T reference point or coincident S and T reference point of implementations conforming to EN 300 138-1 [2].
2 References
The following documents contain provisions which, through reference in this text, constitute provisions of the present
document.
• References are either specific (identified by date of publication, edition number, version number, etc.) or
non-specific.
• For a specific reference, subsequent revisions do not apply.
• For a non-specific reference, the latest version applies.
• A non-specific reference to an ETS shall also be taken to refer to later versions published as an EN with the same
number.
[1] ETSI EN 300 403-1: "Integrated Services Digital Network (ISDN); Digital Subscriber Signalling
System No. one (DSS1) protocol; Signalling network layer for circuit-mode basic call control;
Part 1: Protocol specification [ITU-T Recommendation Q.931 (1993), modified]".
[2] ETSI EN 300 138-1 (V1.3): "Integrated Services Digital Network (ISDN); Closed User Group
(CUG) supplementary service; Digital Subscriber Signalling System No. one (DSS1) protocol;
Part 1: Protocol specification".
[3] ETSI EN 300 138-2 (V1.3): "Integrated Services Digital Network (ISDN); Closed User Group
(CUG) supplementary service; Digital Subscriber Signalling System No. one (DSS1) protocol;
Part 2: Protocol Implementation Conformance Statement (PICS) proforma specification".
[4] ETSI EN 300 138-3 (V1.3): "Integrated Services Digital Network (ISDN); Closed User Group
(CUG) supplementary service; Digital Subscriber Signalling System No. one (DSS1) protocol;
Part 3: Test Suite Structure and Test Purposes (TSS&TP) specification for the user".
[5] ETSI EN 300 196-1: "Integrated Services Digital Network (ISDN); Generic functional protocol for
the support of supplementary services; Digital Subscriber Signalling System No. one (DSS1)
protocol; Part 1: Protocol specification".
[6] ISO/IEC 9646-1 (1994): "Information technology; Open Systems Interconnection; Conformance
testing methodology and framework; Part 1: General concepts".
[7] ISO/IEC 9646-2 (1994): "Information technology; Open Systems Interconnection; Conformance
testing methodology and framework; Part 2: Abstract Test Suite specification".
[8] ISO/IEC 9646-3 (1998): "Information technology; Open Systems Interconnection; Conformance
testing methodology and framework; Part 3: The Tree and Tabular Combined Notation (TTCN)".
[9] ISO/IEC 9646-4 (1994): "Information technology; Open Systems Interconnection; Conformance
testing methodology and framework; Part 4: Test realization".
ETSI
7 ETSI EN 300 138-4 V1.4.3 (2000-05)
[10] 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".
[11] ITU-T Recommendation I.411 (1993): "ISDN user-network interfaces - Reference configurations".
[12] CCITT Recommendation X.209 (1988): "Specification of basic encoding rules for Abstract Syntax
Notation One (ASN.1)".
[13] ETSI ETS 300 102: "Integrated Services Digital Network (ISDN); User-network interface layer 3;
Specifications for basic call control".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
Abstract Test Suite (ATS): see ISO/IEC 9646-1 [6]
Implementation Under Test (IUT): see ISO/IEC 9646-1 [6]
Lower Tester (LT): see ISO/IEC 9646-1 [6]
Point of Control and Observation (PCO): see ISO/IEC 9646-1 [6]
Protocol Conformance Test Report (PCTR): see ISO/IEC 9646-1 [6]
Protocol Implementation Conformance Statement (PICS): see ISO/IEC 9646-1 [6]
PICS proforma: see ISO/IEC 9646-1 [6]
Protocol Implementation eXtra Information for Testing (PIXIT): see ISO/IEC 9646-1 [6]
PIXIT proforma: see ISO/IEC 9646-1 [6]
System Under Test (SUT): see ISO/IEC 9646-1 [6]
UpperTester(UT): see ISO/IEC 9646-1 [6]
3.2 Abbreviations
For the purposes of the present document, the following abbreviations apply:
ASP Abstract Service Primitive
ATM Abstract Test Method
ATS Abstract Test Suite
BER Basic Encoding Rules
CUG Closed User Group
ExTS Executable Test Suite
IUT Implementation Under Test
LT Lower Tester
MOT Means Of Testing
PCO Point of Control and Observation
PCTR Protocol Conformance Test Report
PDU Protocol Data Unit
PICS Protocol Implementation Conformance Statement
PIXIT Protocol Implementation eXtra Information for Testing
SUT System Under Test
TCP Test Co-ordination Procedures
ETSI
8 ETSI EN 300 138-4 V1.4.3 (2000-05)
TP Test Purpose
TTCN Tree and Tabular Combined Notation
UT Upper Tester
4 Abstract Test Method (ATM)
The remote test method is applied for the CUG user ATS. The Point of Control and Observation (PCO) resides at the
service access point between layers 2 and 3. This PCO is named "L" (for Lower). The L PCO is used to control and
observe the behaviour of the Implementation Under Test (IUT) and test case verdicts are assigned depending on the
behaviour observed at this PCO.
Tester SUT
LT IUT
PCO
Layer 2 Layer 2
Layer 1 Layer 1
Service provider
Figure 1: Remote test method
ISO/IEC 9646-2 [7] allows the informal expression of Test Co-ordination Procedures (TCP) between the System Under
Test (SUT) upper layer(s) and the Lower Tester (LT). In the ATS contained in annex C, TCP is achieved by use of a
second "informal" PCO, called "O" (for Operator). This PCO is used to specify control but not observation above the
IUT and consequently, events at this PCO are never used to generate test case verdicts. The use of this O PCO is
regarded as a preferred alternative to the use of the implicit send event, in that it allows the ATS to specify in a clear and
meaningful way what actions are required to be performed on the IUT.
5 Untestable test purposes
There are no untestable test purposes associated with this ATS.
6 ATS conventions
This clause is structured similarly to the structure of a TTCN ATS. However, the names of the subclauses are arranged
in a way more suitable to the present document.
6.1 Declarations part
6.1.1 Type definitions
6.1.1.1 Simple type definitions
Where appropriate, simple types have a length, a value list or a range restriction attached.
Simple types defined as being of some string type (e.g. BIT STRING, OCTET STRING), have a length restriction or a
value list attached.
Simple types, defined as being of INTEGER type, have a value list or a range restriction attached.
ETSI
9 ETSI EN 300 138-4 V1.4.3 (2000-05)
6.1.1.2 Structured type definitions
6.1.1.2.1 TTCN structured type definitions
All structured type definitions are provided with a full name.
All elements in every structured type definition, defined as being of some string type (e.g. BIT STRING, OCTET
STRING), have a length restriction attached.
If an element in a structured type definition is defined as being of a referenced type, the (possible) restriction is defined
in that referenced type.
For information elements the identifier, which is unique for each element, has its type defined as a simple type where the
value list is restricted to the single value which is the identifier itself. This has the advantage that it allows a test system
derived from this ATS to easily identify information elements embedded in messages. An ATS where information
element identifiers are represented as unrestricted types can present difficulties for a derived test system in the case
where it needs to find one information element embedded in a number of others and the constraints for the other
elements have the any-or-omit value. In such a case the test system cannot easily find the beginning of each information
element.
6.1.1.2.2 ASN.1 structured type definitions
ASN.1 has been used for three major reasons. First, types defined in ASN.1 can model problems that "pure" TTCN
cannot. For instance, data structures modelling ordered or unordered sequences of data are preferably defined in ASN.1.
Second, ASN.1 provides a better restriction mechanism for type definitions by using sub-type definitions. Third, it is
necessary to use ASN.1 to reproduce the type definitions for remote operation components as specified in the base
standards.
The fact that ASN.1 provides a better restriction mechanism for type definitions is used for the purpose of achieving
type-compatibility.
Tables 1 and 2 show the typical use of ASN.1. The FIE type in table 1 is written in ASN.1 to permit the use of the SET
OF construction in the components field. Constraints of the FIE type can therefore be written using the SUPERSET
function which allows to match a single component which may be delivered together with a set of other components.
Table 2 shows the reject component type which is defined following the ASN.1 declaration in EN 300 196-1 [5].
Table 1: ASN.1 type definition FIE
ASN.1 Type Definition
Type Name : FIE
Comments : Facility information element taken from EN 300 196; 11.2.2.1.
Specified here for both send & receive event.
Type Definition
SEQUENCE {
informationElementIdentifier FIE_I,
length FIE_LengthType,
extBit BIT STRING (SIZE (1)),
spareBits BIT STRING (SIZE (2)),
protocolProfile BIT STRING (SIZE (5)),
components SET OF Component }
Table 2: ASN.1 type definition RejectComponent
ASN.1 Type Definition
Type Name : RejectComponent
Comments : Reject Component is not specific to any particular operation. The invokeID may be
used to identify a specific operation.
Type Definition
SEQUENCE {
invokedID CHOICE {
invokeID InvokeIDType,
null NULL },
problem CHOICE {
generalProblem [0] IMPLICIT GeneralProblem,
invokeProblem [1] IMPLICIT InvokeProblem,
returnResultProblem [2] IMPLICIT ReturnResultProblem,
returnErrorProblem [3] IMPLICIT ReturnErrorProblem } }
ETSI
10 ETSI EN 300 138-4 V1.4.3 (2000-05)
Table 3 shows an example of how ASN.1 can be used to model unordered sequences.
Table 3: ASN.1 type definition FIES
ASN.1 Type Definition
Type Name : FIES
Comments :
Type Definition
SET OF FIE
The possibility to use TTCN and ASN.1 in combination is used, i.e. referring to an ASN.1 type from a TTCN type.
6.1.1.3 ASP type definitions
6.1.1.3.1 TTCN ASP type definitions
TTCN ASP type definitions only contain one PDU or no PDU at all. The relationship between an ASP type and a PDU
type is one-to-one. That is, there exists one ASP type definition for each PDU type definition (if that ASP type contains
a PDU).
All TTCN ASP type definitions are provided with a full identifier.
Some ASPs are not parameterized as shown in the example in table 4. Such ASPs are only used for requesting or
receiving service from the lower layer.
Table 4: TTCN ASP type definition DL_REL_IN
TTCN ASP Type Definition
ASP NAME : DL_REL_IN(DL_RELEASE_INDICATION)
PCO Type : SAP
Comments :
Parameter Name | Parameter Type | Comments
Detailed Comments :
Table 5 shows an example of a parameterized ASP. All ASPs containing PDUs contain only that PDU and no other
parameters.
Table 5: TTCN ASP type definition DL_DATA_RQ_ALERT
TTCN ASP Type Definition
ASP NAME : DL_DATA_RQ(DL_DATA_Request)
PCO Type : SAP
Comments : CEId: = (SAPI,CES) mapped onto
DLCI: = (SAPI,TEI)
ASP is used to request the transmission of layer 3 PDUs
Parameter Name | Parameter Type | Comments
mun (MessageUnit) |PDU |
Detailed Comments :
6.1.1.3.2 ASN.1 ASP type definitions
There are no ASN.1 ASP type definitions in the ATS.
6.1.1.4 PDU type definitions
6.1.1.4.1 TTCN PDU type definitions
The TTCN PDU type reflects the actual data being transferred or received. All PDUs are embedded in ASPs.
If a specific PDU type definition contains elements defined in terms of a pre-defined type, that element has a restriction
attached to it.
ETSI
11 ETSI EN 300 138-4 V1.4.3 (2000-05)
6.1.1.4.2 ASN.1 PDU type definitions
There are no ASN.1 PDU type definitions in the ATS.
6.1.2 Test suite constants
No test suite constants are used or defined in this ATS.
6.1.3 Test suite parameters
Each test suite parameter is defined in terms of a predefined type or a referenced type. A referenced type is used when it
is necessary to attach restrictions to these type definitions (it is not allowed to include restrictions directly in the test
suite parameter table). The referenced type can have a length or value restriction attached to it in its declaration table.
6.1.4 Variables
6.1.4.1 Test suite variables
No test suite variables are used or defined in this ATS.
6.1.4.2 Test case variables
Each test case variable is defined in terms of a predefined type or a referenced type. A referenced type is used when it is
necessary to attach restrictions to these type
...