An SDL Implementation of the UMTS Radio Resource Control Protocol Oriented to Conformance Testing

SDL and other related ITU-T formal languages have been revealed as a valid approach to developing software for critical systems, such as telecommunication equipment. In this context, this paper presents the use of SDL to implement one of the most complex part of UMTS networks, the radio resource control protocol (RRC). SDL has been used at all the steps of the design and the implementation process, making use of the automatic code generation capabilities of well-known SDL tools. The resulting system will be integrated as a part of a conformance testing box for 3G mobile phones, namely MINT, a product developed by one of the certification leaders in the industry, CETECOM S.A. The main conclusion obtained from this project is that SDL (together with ASN.l) has good capabilities to design and implement realistic complex systems with a very limited use of external languages, like C. During the development, we have been able to take advantages of its formal basis and tool support for simulation and verification.