ISO/IEC 8882-2:2000 情報技術—システム間の電気通信と情報交換— X.25 DTE適合性テスト—パート2：データリンク層適合性テストスイート | ページ 2

3.1 参照モデル用語

ISO/IEC 7498-1 で定義されている次の用語が使用されています。

• a) (N)-プロトコル データ ユニット (N-PDU) ISO/IEC 8882-2 のこの部分の文脈において。 (N)はレイヤー2なので、N-PDUはPDUと略されます。データリンク層の PDU は「フレーム」とも呼ばれます。
• b)データリンク層

Foreword

ISO (the International Organization for Standardization) and IEC (the International Electrotechnical Commission) form the specialized system for worldwide standardization. National bodies that are members of ISO or IEC participate in the development of International Standards through technical committees established by the respective organization to deal with particular fields of technical activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other international organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the work.

International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, 3.

In the field of information technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1. Draft International Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as an International Standard requires approval by at least 75 % of the national bodies casting a vote.

Attention is drawn to the possibility that some of the elements of this part of ISO/IEC 8882-2 may be the subject of patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.

International Standard ISO/IEC 8882-2 was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology, Subcommittee SC 6, Telecommunications and information exchange between systems.

This third edition cancels and replaces the second edition (ISO/IEC 8882-2:1995), which has been technically revised.

ISO/IEC 8882 consists of the following parts, under the general title Information technology — Telecommunications and information exchange between systems — X.25 DTE conformance testing:

• Part 1: General principles
• Part 2: Data link layer conformance test suite
• Part 3: Packet layer conformance test suite

Annex A forms a normative part of this part of ISO/IEC 8882.

Introduction

This part of ISO/IEC 8882 presents the X.25-DTE Conformance Test Suite for Data Link Layer, described in Tree and Tabular Combined Notation (TTCN).

ISO/IEC 8882-1 explains the objectives and usage of this part of ISO/IEC 8882.

Clause 1 of this part of ISO/IEC 8882-2 is the scope which provides an objective basis for the applicability of the tests within this part of ISO/IEC 8882. Clauses 2 and 3 give the references, definitions and abbreviations used in this part of ISO/IEC 8882. Clause 4 contains information relating to procedures performed in conformance testing. The test suite structure is defined in terms of test groups and subgroups in Table 1. This clause also gives an overview of the test suite. Annex A provides information on the Abstract Test Suite for the X.25-DTE LAPB Data Link Layer protocol both in TTCN GR and TTCN MP format.

1 Scope

This part of ISO/IEC 8882 defines an abstract test suite for testing the conformance of the Data Link Layer of an IUT with respect to ISO/IEC 7776(1986, 1995) or the ITU-T Recommendation X.25 (1980, 1984, 1988, 1993).

Conformance of a Data Terminal Equipment (DTE) to the above ISO International Standard or ITU-T Recommendations is tested using a dedicated circuit between the tester and the DTE. It is noted that ITU-T Recommendations X.25 (1980), X.25 (1984), X.25 (1988) and X.25 (1993) are written from the perspective of a DCE and therefore do not always explicitly specify the DTE's operation. In such cases it is assumed that recommended operation of a DTE is included by implication because of the need to communicate with X.25 DCE's. This part of ISO/IEC 8882 excludes the testing of the LAP procedures given in the ITU-T Recommendations.

The tests in this part of ISO/IEC 8882 are designed for six possible interworking situations, shown in Figure 1. This part specifies tests for all six cases shown in Figure 1, but recognizes that not every test may apply to a particular DTE. A test selection procedure has to be performed to determine the applicability of a test to a particular DTE. Such selection will be based on the PICS and the PIXIT.

In the rest of this part of ISO/IEC 8882, the term"X.25 standards" means all four of ITU-T Recommendations X.25 (1980), X.25 (1984), X.25 (1988), X.25 (1993), and International Standards ISO/IEC 7776 (1995) and ISO/IEC 7776 (1986), unless stated otherwise.

2 Normative references

The following standards contain provisions which, through reference in this text, constitute provisions of this part of ISO/IEC 8882. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this part of ISO/IEC 8882 are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards.

3 Terms, definitions and abbreviations

For the purposes of this part of ISO/IEC 8882, the terms and definitions given in 3.4 and in the following International Standards apply:

• a) ISO/IEC 7498-1;
• b) ISO/IEC 9646;
• c) ISO/IEC 8882-1.

3.2 Conformance testing terms

The following terms are used from the Conformance Testing Methodology and Framework, International Standard ISO/IEC 9646:

• a) Conformance Testing
• b) Conformance Test Suite
• c) Implementation Under Test (IUT)
• d) Protocol Implementation Conformance Statement (PICS)
• e) Protocol Implementation Extra Information for Testing (PIXIT)
• f) Static Conformance Requirements (SCR)
• g) Behavior Testing
• h) Test Purpose
• i) Tree and Tabular Combined Notation (TTCN)
• j) Preamble
• k) Test Body
• l) Test Step
• m) Test Event
• n) Abstract Service Primitive (ASP)
• o) Test Group
• p) Abstract Test Suite (ATS)
• q) Executable Test Suite (ETS)
• r) Test Verdicts
• s) Lower Tester
• t) Upper Tester
• u) Test Methods
• v) Remote Single (layer) Test Method (RS method)
• w) Valid Test Event
• x) Invalid Test Event
• y) Inopportune Test Event
• z) Point of Control and Observation (PCO)

3.3 X.25-DTE conformance testing terms

This part of ISO/IEC 8882-2 makes use of the following terms defined in ISO/IEC 8882-1:

• a) Improper PDU
• b) Proper PDU
• c) Test Case
• d) Test Subgroup
• e) Tester

3.4 Additional terms and definitions

This test suite uses test subgroups for proper, improper and inopportune frames to test the IUT behavior. These terms are defined below.

3.5 Abbreviations

The abbreviation IUT is used in this part of ISO/IEC 8882-2 to refer to an X.25-DTE under test.