gsm data services within calm-based its solutions
Transport telematics applications require availability of the seamless secure communications solutions covering selected usually wide areas and frequently serving extensive number of moving objects. Provided service is required to be served with selectable levels of service quality. There is available quite extensive range of wireless technologies provided either by public providers or privately. Described expectations lead to multi-path solutions where different wireless services are combined and selection of the best possible alternative is based on L3/L2 switching supported by different system level of the decision processes. Such approach is supported by ISO/CEN activities usually called as CALM family of standards. Relevant decisions must be based on deep understanding of applied technologies and precisely quantified requirements on system as well as subsystems performance indicators tolerance range. These limits are identified with aim to keep service provisioning on appropriate quality level with minimal impact of continuously changed conditions in time and served area. To cover identified system requirements each applied technology must be studied in detail to identify specific available performance indicators as well as their internal interactions to be able to monitor and manage each technology on appropriate quality level. This paper presents results of GSM data services laboratory measurement. Obtained results are compared with results of already published WiMax service analysis. These two access technologies belong definitely to the core alternatives applied within ITS and presented analysis represents necessary basis for future ITS CALM based system implementations.
telematics performance indicators seamless communications access service signal to noise ratio intelligent transport system