Dieter Hogrefe

The CCITT-specification and description language SDL

Abstract SDL has been designed to specify and describe the functional behaviour of telecommunication systems. It has been used in a variety of fields, including data communication protocol specification. This paper briefly explains the basic concepts of the latest version of the language, known as SDL88, as it has been recommended by CCITT in 1987.

Testing of Communicating Systems

Keynote Speech I.- Prediction = Power.- Next Generation Networks, IP and UMTS.- UMTS Terminal Testing: A Practical Perspective.- Testing of 3G 1xEV-DV Stack - A Case Study.- Testing SIP Call Flows Using XML Protocol Templates.- Towards Modeling and Testing of IP Routing Protocols.- TTCN-3.- An Intuitive TTCN-3 Data Presentation Format.- The UML 2.0 Testing Profile and Its Relation to TTCN-3.- Realizing Distributed TTCN-3 Test Systems with TCI.- TimedTTCN-3 Based Graphical Real-Time Test Specification.- Keynote Speech II.- Interoperabolity Events Complementing Conformance Testing Activities.- Automata-Based Methodology.- Testing Transition Systems with Input and Output Testers.- Generating Checking Sequences for a Distributed Test Architecture.- Conformance of Distributed Systems.- An Automata-Based Approach to Property Testing in Event Traces.- Fault Diagnosis in Extended Finite State Machines.- A Guided Method for Testing Timed Input Output Automata.- Interoperability Testing.- Interoperability Testing Based on a Fault Model for a System of Communicating FSMs.- Framework and Model for Automated Interoperability Test and Its Application to ROHC.- Keynote Speech III.- TestNet: Lets Test Together!.- Test Design, Tools and Methodology.- An Open Framework for Managed Regression Testing.- TUB-TCI An Architecture for Dynamic Deployment of Test Components.- Fast Testing of Critical Properties through Passive Testing.

A review of mobility support paradigms for the internet

Abstract With the development of mobile communication and Internet technology, there is a strong need to provide connectivity for roaming devices to communicate to other communication end point in the Internet at any time and anywhere. The key issue of this vision is how to support mobility in TCP/IP networks. In this paper, we review the TCP/IP protocol stack and analyze the problems associated with it in a mobile environment. We then investigate the mobility support techniques and existing solutions to provide mobility support in the Internet. We classify the proposed solutions based on the protocol layers and present examples for each category. We also provide a comparison of the different solutions belonging to different categories and in the same category, including their advantages and disadvantages, and conclude that there is no single solution perfectly addresses mobility support for the Internet. We conclude this survey with a recommendation of features that need to be satisfied in Internet mobility support.

An introduction to the testing and test control notation (TTCN-3)

The testing and test control notation (TTCN-3) is a new test specification and test implementation language that supports all kinds of black-box testing of distributed systems. TTCN-3 was developed in the years 1999 to 2002 at the European Telecommunications Standards Institute (ETSI), as a redesign of the tree and tabular combined notation (TTCN) standard (ITU-T Rec. X.292). TTCN-3 is built from a textual core language that provides interfaces to different data description languages and the possibility of different presentation formats. This makes TTCN-3 quite universal and application independent. TTCN-3 is being published as the ITU-T Rec. Z.140 series. This paper provides an introduction to TTCN-3. This includes an overall view of the TTCN-3 core language, a description of the existing presentation formats, an explanation of the implementation of TTCN-3-based test systems and a discussion about the current usage and the future of the language. The authors all participated in the work within ETSI.

NSIS: a new extensible IP signaling protocol suite

In the last few years it number of applications have emerged that can benefit from network-layer signaling (i.e., the installation, maintenance, and removal of control state in network elements). These applications include path-coupled and path-decoupled quality of service management and resource allocation, as well its network debugging, NAT, and firewall control. These applications call for an extensible and securable signaling protocol. This article discusses some of the recent standardization efforts in the IETF for it new extensible IP signaling protocol suite (NSIS). We describe the design of the NSIS protocol suite, and compare it with RSVP, the current Internet QoS signaling protocol.

On the Design of the New Testing Language TTCN-3

This paper gives an overview of the main concepts and features of the new testing language TTCN version 3 (TTCN-3). TTCN-3 is a complete new testing language built from a textual core notation on which a number of different presentation formats are possible. This makes TTCN-3 quite universal and application independent. One of the standardised presentation formats is based on the tree and tabular format from previous TTCN versions and another standardised presentation format is based on MSCs. TTCN-3 is a modular language and has a similar look and feel to a typical programming language. However, in addition to the typical programming constructs it contains all the important features necessary to specify test suites.

Autolink-a tool for automatic test generation from SDL specifications

Due to an increasing interest in SDL (Specification and Description Language), MSC (Message Sequence Charts) and TTCN (Tree and Tabular Combined Notation) based tools for validation and test generation, Telelogic AB and the Institute for Telematics at the University of Lu/spl uml/beck are cooperating in a research and development project which adds new test generation facilities to Telelogics Tau tool set. The result of that cooperation is Autolink, a software tool which supports the automatic generation of TTCN test suites based on SDL and MSC specifications. The project follows a pragmatic approach and is driven by practical experience. Autolink has been used by the European Telecommunications Standards Institute (ETSI) to develop a test suite for Core INAP CS-2 (Intelligent Network Application Protocol, Capability Set 2).

Autolink - Putting SDL-Based Test Generation Into Practice

Autolink is a tool for automatic test generation. It allows to generate TTCN test suites based on a given SDL specification and MSC requirements. The first big challenge for Autolink was the creation of a test suite for the Intelligent Network Application Protocol at ETSI. In this paper we discuss our experience in applying Autolink to a real-life protocol and the improvements of Autolink which were developed during this project. We also present future enhancements which will further ease the work of test suite developers.

Towards the Industrial Use of Validation Techniques and Automatic Test Generation Methods for SDL Specifications

Publisher Summary This chapter shows the possibilities for tool-assisted test case generation using the SDT Validator and ITEX. Practical use of these methods indicates that an improvement of the test case generation facilities is needed and is possible. Therefore, the AUTOLINK project has been set up. The first, basic version of the AUTOLINK tool is described in the chapter. The ITU-T Specification and Description Language (SDL) is worldwide the most successful standardized formal description technique. SDL has been used successfully in industrial projects and for standardization purposes. The SDT/ITEX tools from Telelogic AB are one of the most successful commercial SDL tool sets that provide a complete environment for the development of SDL specifications, SDL-based implementations, and The Tree and Tabular Combined Notation (TTCN)-based test suites. For this, they include graphical editors, analyzers, simulation tools, various browsers, application code generators adapted to different real-time kernels, and further support tools. The Validator provides engineers with the possibility to increase the quality of their work and to automate time-consuming tasks.

Towards robust key extraction from multipath wireless channels

This paper tackles the problem of generating shared secret keys based on the physical characteristics of the wireless channel. We propose intelligent quantization mechanisms for key generation, achieving high secret bits generation rate. Moreover, some practical issues affecting the performance of the key generation mechanism are deeply investigated. Mainly, we investigate the effects of delay and mobility on the performance and we enhance the key generation mechanism accordingly. As a result, this paper presents a framework towards robust key generation from multipath wireless channels.