Tests of the ATLAS Trigger and Data Acquisition System

The complexity of the Trigger and Data AcQuisition (DAQ) systems at LHC experiments has required a long phase of prototyping both for software and hardware technologies. The development of the core aspects of the DAQ for ATLAS is now well advanced and large effort is put into the validation of the performance and the scalability of the most crucial components. This paper presents the results obtained on two testbeds used to verify the functionality and performance of the read out system and the run control.