Using TTCN-3 for Conformance Testing Text-based Internet Protocol Implementations

Fényes Gábor <gabor.fenyes@eth.ericsson.se>

Ericsson Magyarország Kft.

Fényes Gábor <gabor.fenyes@eth.ericsson.se>

Ericsson Magyarország Kft.

The Conformance and Software Test Lab at Ericsson Hungary was first in the world to present a TTCN-3 core language compiler and test executor prototype with real test campaigns. This latest version of the Tree and Tabular Combined Notation developed by ETSI aims to make an even wider range of people use the already popular test platform. New features such as the programming language-like interface have been introduced while retaining several frequently used older functionality. Indeed, rapid development of both conformance and performance test suites for several byte-encoded Internet protocol implementations (including IPv6, DNS, and even Diameter) was shown to be possible with ease using TTCN-3.

Many of today’s Internet protocols, however, are not byte-encoded. In particular, IETF protocols that follow the general message formatting of RFC 822 are text-based for effortless decoding by humans. Such legibility in SMTP, HTTP, and most recently in SIP raises several questions in the straightforwardness of testing their implementations with TTCN-3. The solution of the arising difficulties and dilemmas most commonly requires a decision to either allow greater testing flexibility or greater automation for test generation.

Addressing the practical issues that occur when one uses TTCN-3 to conformance test text-based protocol implementations is the ultimate goal of the presentation. In order to understand the concerns, we begin with quick overviews of conformance testing in practice and of TTCN-3. A little insight into how tests are developed with the TTCN-3 test executor prototype is also highlighted.