After successful completion of the R&D project "Future framework for traffic control technology according to technical procurement requirements for outstations (TLS)" - which H/B carried out on behalf of the Federal Highways Research Institute (BASt) - the final deliverable has now being published by the federal ministry of transport as research report no. 956 in their series on "Road construction and road traffic engineering research". The project's aim was to highlight a future migration path that would allow the TLS - which are of outmost importance for public procurement of ITS equipment - to adapt to the realities of information and communication technologies in the 21st century. Therefore, the data structures underlying the TLS had to be re-modelled in a platform-independent manner.

The project team started with a sound analysis that led to a specification of a data modelling methodology, based on up-to-date modelling standards from the IT domain (UML - Unified Modeling Language - see www.omg.org/uml for details; equivalent to ISO/IEC standard 19501).

Based on this approach, the TLS data structure were re-factored into a data model which was captured in a database using a software engineering tool and graphically represented in so called "class diagrams". It was crucial that these new data elements also included all required information to transform them back into the current TLS datagram structure, which enables a viable migration path by allowing systems in mixed-mode operation.

In a subsequent step, the communication sequences oft he higher TLS protocol layers (OSI7) were described using the same methodology. The existing TLS relies entirely on textual specifications here, which frequently led to diverging implementer interpretations and consequently resulted in interoperability problems. The project proved that TLS data exchange can fit very well into the service oriented architecture (SOA - Service Oriented Architecture - see www.omg.org/soa) paradigm, which is today's IT domain collaboration standard for distributed, loosely-coupled systems.

The results of this research effort forms an important baseline for migration of the TLS into an up-to-date communication infrastructure. The research report recommends a test implementation of a service oriented TLS communication infrastructure based on the most widely spread SOA protocol suite for so called Web Services (WSDL, SOAP). This test should also be used to prove the claimed mixed-mode operation capabilities in practice.

[Pögel, Kaltwasser, "Plattformunabhängige Modellierung der TLS-Daten", Heft 956, BMVBS (Hrsg.)]